Few in the UK seem to realize that our policy for controlling COVID-19 differs radically from the WHO recommendations. The WHO say we need to test all suspected cases, quarantine them, trace all close contacts and ask them to self isolate. The UK was doing that until the 12th March when they decided to stop testing for mild cases.
skip to: Request for urgent evidence based science debate? Also if in the UK and worried, see: You can protect yourself.
For discussion of the model the UK uses for its policy guidelines, and its assumptions, skip to: The Imperial college London study .Also - see Contents
The current UK policy is based on a fictional influenza disease such as is used for pandemic planning exercises. But this is not an exercise, it is the real world. COVID-19 is not going to behave like their fictional disease if their model doesn't match the real world data.
In particular the WHO make a distinction between a respiratory disease that is airborne, and one that is spread only via coughs and sneezes.
Flu is airborne - it can spread a short distance through the air on tiny droplets that we exhale as we breath, known as aerosols. These stay in the air for minutes to hours unlike the larger droplets of coughs and sneezes. See "Flu spreads without coughing or sneezing". In ordinary situations COVID-19 is not airborne. It just spreads through the larger droplets of coughs and sneezes. COVID19 is only airborne after certain medical procedures such as intubation, and this is why such a high standard of personal protection is needed for intensive care units and caring for patients on ventilators. But in ordinary everyday life, no, it is not airborne (see The coronavirus COVID-19 is NOT AIRBORNE).
SARS is airborne. In one incident, 20 people got SARS from one infected person on Air China Flight 112. This doesn't happen with COVID-19.
There are only particular situations where contact tracing can work for a respiratory disease. But this happens to be just that situation. China, Singapore and South Korea have proven by doing. Any model used for planning has to at a minimum be able to model what they did.
This summarizes some of the main differences between this fictional pandemic and the real world data as used by the WHO.:
Text on image:
Imperial college - used by UK Gov.Hypothetical disease based on influenza
Airborne over short distances
- 1/3 Community spread
- 1/3 workplaces and schools
- 1/3 households
Around 1/3 don't feel ill
Most infection is from 12 hours before
through to 7 days after symptoms.
[Most of this information is from: Impact of non-pharmaceutical interventions (NPIs) to reduce COVID-19 mortality and healthcare demand]World Health Organization
COVID-19 - actual data
Not airborne
Most transmission is in households
- Genuine community spread rare
- Schools unknown but possibly none
workplaces, mainly close
traceable contacts
- 80% households typical
- Prisons / hospitals / care homes
Most feel ill even with mild version
Infection from 2 days before symptoms
to 14 days after symptoms cease.[Most of this information is from the Report of the WHO-China Joint Mission on Coronavirus Disease 2019 (COVID-19) ]
Image background is based on the John Hopkins university map tracking COVID-19 cases as of 21st March: Wuhan Coronavirus (2019-nCoV) Global Cases
The other main difference is that COVID19 has an affinity for the lower respiratory tract. It has to infect via the upper respiratory tract but it doesn't have an affinity for those cells and doesn't transmit easily - typically only 1 in 10 gets infected in a household instead of 100% as happens for flu.
It makes up for that though because the patient with COVID-19 is infectious for a very long time up to 14 days after they feel completely recovered.
These are significant differences. Singapore controlled it with almost no physical distancing and no lock downs. That would be impossible with 'flu. Bill Gates has been closely involved in the field of modeling epidemics and talking about this team's models he wrote
The experience in China is the most critical data we have. They did their “shut down” and were able to reduce the number of cases. They are testing widely so they see rebounds immediately and so far there have not been a lot. They avoided widespread infection. The Imperial model does not match this experience. Models are only as good as the assumptions put into them. People are working on models that match what we are seeing more closely and they will become a key tool. A group called Institute for Disease Modeling that I fund is one of the groups working with others on this.
The UK's physical distancing will greatly reduce the transmission of flu as that is what it is designed for. However this is not flu.
The WHO stress that the backbone of our response needs to be case finding, quarantine, contact tracing and isolation. The way it spreads is such that nearly everyone infected is an easily traceable contact of the known COVID-19 case.
We don't have time to learn from our mistakes. Every three days of delay doubles our problems. As scientists in Italy said two weeks ago, in their open letter to scientists in other countries:
In just 3 weeks from the beginning of the outbreak, the virus has reached more than 10.000 infected people.
...
If Italy had strongly acted just 10 days ago, and that is more or less where you are now, there would have been much fewer deaths and economic tumble.
South Korea and China should be taken as the example to follow to stop this epidemic. There is no other way.
So please, make your best effort to urge your government to act now! Time is our common enemy as the virus is very fast and really lethal.
Every minute is exceptionally important as it means saving lives. Don’t waste it!
Take care.
Open letter to the scientific community (click through to see the letter, signed by many professors)
The one thing we can be sure of is that these measures have not been tested by any other country as the UK (and now the Netherlands) are the first to attempt to control COVID-19 in this way.
We know that the contact tracing and the quarantine recommendations of the WHO work. We don't know what the outcome will be for these new methods used by the UK.
This is another article I'm writing to support people we help in the Facebook Doomsday Debunked group, that find us because they get scared, sometimes to the point of feeling suicidal about it, by such stories.
Please share this especially with scientists, politicians and decision makers in the UK
I wrote this not to alarm people but to try to put pressure on our government to change, and not a week from now, not even a few days from now but right away. For the people I help I reassure them that they can protect themselves at least from the pandemic, and by doing so are also preventing transmission chains from them through to others. See: You can protect yourself
Even when it gets very serious we can turn it around. The Chinese showed that in Wuhan and meanwhile the UK and other countries have now shown they are prepared to take very drastic measures to stop it. The question really is, can they take the right ones?
skip to: Test your understanding of COVID-19
I am calling for a debate, with utmost urgency, on the scientific evidence basis of the UK's policy.
It should include invited experts from the WHO, such as Dr Bruce Aylward and Dr Maria van Kerkove, both of whom spent 9 days studying the situation in China including a day and a half in Wuhan while preparing the Report of the WHO-China Joint Mission on Coronavirus Disease 2019 (COVID-19).
This is too urgent to let slide. I am not talking about a debate a week from now, or two weeks from now. But a top priority international teleconference right now, in public, examining the science behind the UK's approach, and its validity or otherwise for guiding our policy decisions.
We have to raise awareness of these issues and look at them directly with the clear eye of science and evidence. It should be public too, so that we can all follow the discussion and hear the arguments on both sides of the debate.
What do you think? If you have other suggestions do say.
If you are in the UK you can also help by writing an email to your local MP about it. You need to include your postcode in the letter so that they can check you are a constituent. This is the one I wrote (not got an answer back yet).
skip to: Answers to the test
I live in the UK and few of the others in my country are aware of how radically different the UK policy is from the WHO recommendations. Our news stories never mention the WHO recommendations, which they give with every press briefing. To test your understanding answer these questions. Readers in Singapore, South Korea or China and indeed many countries are likely to get the right answers. But how do you fare in the UK?
Answers below.
For each one, what does the WHO say based on the scientific evidence they have and the experience of other countries?
The background to this image is the map from the WHO dashboard as last updated 24th March, 18:00 CET.
skip to: Our priorities for COVID19 according to the WHO
skip to: Will the new UK methods even slow it down?
Our priorities for COVID are:
The lock down and physical distancing are only a minor component because the virus hardly spreads that way.
The main reason for doing that is to stop the virus from spreading to new locations. But it doesn’t stop it spreading, just keeps it contained within a more defined region.
Singapore and South Korea did it with almost no physical distancing.
skip to: Precious second window of opportunity
Though designed to slow down and delay the spread of COVID19 some aspects of the UK policy might perhaps even make it worse.
First, WHO repeatedly stress that there is a significant risk of a COVID-19 patient infecting others in the same household (around 80% of transmissions in China was through households). It's a top priority to prevent infection of other members of the household. The data from China shows that only 3 to 10 in 100 in the household gets it from a COVID-19 patient (see UK government assumes if one person in a household has COVID-190 most will get it - report says 10% or less below)
The UK policy of quarantining households together doubles the number of contacts within the household (estimate from the UK Covid response team's own paper see Recommendations based on this fictional flu hypothesis below). With the fictional disease this doesn't matter because 100% get it anyway but in the real world, this could increase the numbers infected.
However the UK government is advising people to isolate themselves from any vulnerable person in the house. The Scottish branch of the NHS advises people who have COVID-19 like symptoms to isolate from the rest of the household with separate cutlery etc. That should help reduce the number of infections within a household for COVID-19 somewhat. It is not as stringent as the WHO advice. But it is certainly a lot better than nothing.
Second, the WHO stress the importance of keeping COVID-19 out of the health care system which can be a significant amplifier of a new infectious disease. See Risks of infecting health care system (below)
The UK advise doctors in the same way as everyone else that they are no longer infectious after 7 days of quarantine. This can bring COVID-19 into hospitals. The UK only tests a patient who is admitted to hospital with suspected COVID-19 if they require at least an overnight stay. See the guidelines here. Both these guidelines have been in place for a week now. It might already have impacted on the health workers. As of 26th March, according to the BBC, London is reporting that some hospitals have 20 - 50% of the health care professionals absent because of sickness or self isolating. They don't say how many have COVID-19 and I don't think they know.
China took great care to make sure patients with COVID-19 and doctors with COVID-19 came nowhere near their general hospitals. Even with many precautions China had occasional infections of hospitals by patients. The UK is not taking any of those precautions,
Also,doctors will be inspecting many patients and treating them for other conditions not knowing if the patient or themselves have the disease.
I can't find an estimate of the number of doctors will die - but if the spread through our hospitals stops only through "herd immunity", and half get it in a hospital, as a rough estimate a thousand doctors die of this pandemic and getting on for a thousand nurses (more if elderly nurses return from retirement to help), with the most elderly doctors and nurses worst affected. It is a very rough estimate, as I have not been able to find any published estimates. Please do say if you know of an estimate. See : Devastating effect on doctors and nurses (below)
Many times that number of doctors and nurses would become sick, and many will need treatment in intensive care units. But with the UK policy, a significant fraction will be sick themselves and others tied up in caring for the doctors and nurses that got sick.
Clearly we would not let it get that far before starting serious measures to protect health care workers from COVID-19. But how far will it get before the UK notices what is happening and acts vigorously to protect its healthcare system from COVID19?
Part of the problem here is the slow progression of the disease. You start to notice the problem well over a week after the decision that caused it and then it becomes more obvious over the following weeks.
Right now they are moving in the opposite direction. On March 19th they decided they would no longer treat COVID19 as a high consequence infectious disease, reducing the level of protection for health workers treating known COVID-19 patients. See UK no longer considers COVID19 to be a high consequence infectious disease (below)
skip to: You can protect yourself
Make no mistake this is a serious disease. Even with young people a significant percentage will be on ventilators for up to six weeks and the worst cases will take months to recover completely and some will die. If it spreads through our care homes with elderly people or our hospitals many patients will die. Then there is the lack of ventilators to treat the worst cases. It is not just the machines, each ventilator needs 2-3 health care professionals monitoring them 24/7.
Officially we have over 8 ,000 cases as of 24th March, but we know that we are missing most of the mild ones. Since 12th March when we had 586 cases we are no longer testing mild cases. If we suppose we are only finding 20% of the cases now, then there are four times as many cases missing as the ones we know of, so we may already have as many as 40,000 cases.
An increase from 500 to 10,000 in 12 days means another 12 days at the same increase takes us to 200,000 cases. If it is 40,000 cases now and we continue at the same rate of increase, it takes us to 3.2 million cases by 12 days from now. This epidemic has increased so fast in the UK that we haven't yet reached the stage where many start dying (about 10 days in) but we will see this happening soon and a sudden increase in the need for ventilators. Within a few days it will become more and more noticeable.
This is something that not even the best health care systems will be able to support. Dr Tedros said:
"If anything is going to hurt the world, it’s a moral decay. And not taking the death of the elderly or the senior citizens as a serious issue is one of the moral decays."
We can still get back on track and turn it around.
The WHO call this a second precious window of opportunity. Dr Mike Ryan put it like this.
All that we get from movement restrictions and people staying at home and all of these measures; we buy some time, we take the heat out of the epidemic or the pandemic, we buy some time.
But we may then need to find strategies and tactics that get us to move forward and we have to make those decisions.
Each government will have to make those decisions. We're working hard to provide advice to governments on how to do that but very, very clearly in order to move forward a scale-up - and I mean a massive scale-up - in public health capacities to do case finding, isolation, quarantine of contacts and being able to go after the virus rather than the virus coming after us, is one of the key ways we can move forward and we'll be coming back to governments and in public around our advice on this to governments.
There is a very, very precious window now in which we can prepare to do that.
As he says, it requires a massive scale up, but it is not impossible, countries are innovating and rising to the challenge. South Korea traced over 300,000 contacts of over 8000 people. China at its hieght traced all the contacts of more than 70,000 people. Singapore has released an app that they use for automatic proximity sensing via bluetoooth for later contact tracing.
Anyone can do this tracing; they don't have to be health workers. The more the UK delays the larger the operation will be to trace them all and civil servants and voluntary organizations will be needed in vast numbers for the operation, and software and databases to co-ordinate it all but we can do it. We have to try, it's the only way to save thousands of lives.
See my: Contact tracing has to be methodical and thorough (below).
skip to: Vital to respond effectively and promptly
Meanwhile you can do a lot to protect yourself with simple effective measures. If you are in the UK and aren’t doing these yet, I recommend starting on them right away. Our government hasn't explained this clearly enough - at least most that I talk to via private messaging in the UK who contact me scared of COVID-19 do not fully understand the importance of this when they first contact me. It is a bit like people not bothering to wear seat belts in cars before "Clunk click Every Trip".
Do you do these four things?
Do this as thoroughly as the experts, and you can say:
"I don't have COVID-19 - I am very low risk".
Dr Bruce Aylward said that immediately after he returned from Wuhan. He knew he was safe because he did those things.
The WHO stress that these simple measures save lives. They are not hard to do if you make them into a habit. More details here:
We all need to carefully follow the instructions to protect ourselves and your loved ones and tell everyone else about what they need to do to stay safe. These instructions work. You also help others too, every time you do this you are also helping to break the transmission chain to others.
skip to: This virus can be suppressed and controlled
It is vital to respond to this disease in an effective manner promptly. If you don’t, it’s been the experience of other countries that cases increase with rather astonishing speed. With a doubling time of 3 days, it can increase 5-fold in a week. If it continues at this rate, then from 1000 cases you can reach 625.000 cases in four weeks.
Break most of the chains of transmission early when it is only a few cases or a few tens of cases and you can nip it in the bud. Many countries have done that outside China now, including Singapore who adopted these methods right from the start when the first cases arrived there from China. Now nearly all new cases in Singapore are imported from visitors from other countries even though they were amongst the first few countries to be infected by this virus. Many countries have shown that this virus can be controlled. This is what it looked like a few days after the UK's decision to stop containing the virus.
Text on image: China had 0 new cases on 17th March. WHO says question is not whether we can stop it, only if we will!
China peaked 4th Feb
Redefinition of cases spike
South Korea, Japan, Malaysia, Singapore, Phillipines etc Peak around 1st March
Europe & East Med peaking
Americas on the rise
Africa numbers still lowGraphic is from Situation report 57. For more details see my Many Countries Are Stopping COVID19 - Containing Cases Is The Key - Every Day Of Delay Makes It Harder For Countries & The World
You don't have to find everyone to stop a pandemic, e.g. if you break 75% of the transmission chains it soon stops. These countries were not finding everyone but nearly everyone and they were stopping it. The Imperial college model can't explain this data.
With 'flu then 33% are asymptomatic making it almost impossible to stop because you can never stop more than 67% and then you also have a third of the transmission happening randomly in the community with 'flu because it is airborne over short distances while COVID-19 is not. Combine those together and you can never stop more than 44.44% of 'flu transmission with this method of contact tracing and isolation, so it can at most slow it down.
However Singapore and other countries have shown that with extensive testing, and rigorous contact tracing you can stop well over 75% of COVID-19 transmission. To give a simple example of how this works, suppose 100 patients would normally infect 200 others. Then it continues
100 → 200 → 400 → 800 → 1600
If this happens every 3 days say, then 12 days later you have 3,100 cases from your original 100.
If you can break 3/4 of the chains of transmission it goes
100 → 50 → 25 → 13 → 6 → 3 → 2 → 1
Now it stops at 200 cases after 21 days. Of course in practice it’s more variable than this but it is going to stop well within a month starting from 100 cases.
As an example of this at work, Singapore on 20th March had 385 cases. Of the 40 new cases on that day, only 3 were new transmissions local to Singapore and 3 more were transmissions from other local cases while all the large clusters had no new transmissions. Figures like this would be impossible to achieve with ‘flu.
These are accurate figures too. There can't be hidden problems in Singapore. It has the best data we have on COVID19, with thorough nation wide diagnostic testing in a population of 5 million. It has had this testing in place since 28th January. See my
skip to: UK no longer considers COVID19 to be a high consequence infectious disease
In a WHO press briefing Dr Tedros said:
"Several countries have demonstrated that this virus can be suppressed and controlled. The challenge for many countries who are now dealing with large clusters or community transmission is not whether they can do the same; it's whether they will."
In the press briefing on the 18th March he said
WHO continues to recommend that isolating, testing and treating every suspected case, and tracing every contact, must be the backbone of the response in every country. This is the best hope of preventing widespread community transmission.
WHO Director-General's opening remarks at the media briefing on COVID-19 - 18 March 2020
We can stop it. We can still turn this around. As Dr Tedros said:
We also need to celebrate our successes. Yesterday, Wuhan reported no new cases for the first time since the outbreak started. Wuhan provides hope for the rest of the world, that even the most severe situation can be turned around.
The UK are going the other direction. On 19th March, the UK decided COVID-19 is no longer considered to be a high consequence infectious disease.
As of 19 March 2020, COVID-19 is no longer considered to be a high consequence infectious diseases High consequence infectious disease (HCID)
...
Cases of COVID-19 are no longer managed by HCID treatment centres only. All healthcare workers managing possible and confirmed cases should follow the updated national infection and prevention (IPC) guidance for COVID-19, which supersedes all previous IPC guidance for COVID-19. This guidance includes instructions about different personal protective equipment (PPE) ensembles that are appropriate for different clinical scenarios.
They are treating it similar to ‘flu. This has consequences for care.
Once an HCID has been confirmed by appropriate laboratory testing, cases in England should be transferred rapidly to a designated HCID Treatment Centre. Occasionally, highly probable cases may be moved to an HCID Treatment Centre before laboratory results are available.
This lets them reduce the measures needed to protect us from it. The NHS guidelines for protecting doctors and nurses who work with patients with COVID-19 are similar to those of the WHO for countries that face a shortage of personal protection equipment.
See Risks of infecting health care system below, and I discuss it further here:
If half the doctors get it, I estimate that around 1000 will die (compared to 63 doctors that have died so far in Italy). I work out the number that would die based on the Italian death rates for each age group + Chinese death rates for younger ones. I
As of writing this [edit of this article on 30th March 2020], , 1 in 4 of our doctors are off sick or self isolating with family members. If these have COVID-19 or get it from their family, then that woud be 500 would die.
The deaths happen starting at the end of the second week most in the third or later weeks of symptoms. So most won't happen for a few weeks yet of those that are self isolating right now for the first 7 days of mild symptoms.
See my: Devastating effect on doctors and nurses
Their main aim now is to reduce the amount of community spread which they hypothesize to be responsible for a third of the infections and infections in schools and workplaces which they hypothesize to be responsible for another third.
However the real world data from China finds households there to be responsible for around 80% of the infections.
skip to: Risks of infecting health care system
The UK assume that most in the household will get infected anyway. That is presumably true of their hypothetical ‘flu virus. However the big WHO-China study found that typically only 3–10% of those in the same household a a COVID-19 patient gets infected even without taking any precautions. E.g. out of 100 contacts, only 3 - 10 of them will get infected.
In China, human-to-human transmission of the COVID-19 virus is largely occurring in families. … Among 344 clusters involving 1308 cases (out of a total 1836 cases reported) in Guangdong Province and Sichuan Province, most clusters (78%-85%) have occurred in families … preliminary studies ongoing in Guangdong estimate the secondary attack rate in households ranges from 3-10%. Report of the WHO-China Joint Mission
The amount of spread to random people in the community is close to zero for COVID-19. There is no airborne spread, even over short distances, unlike 'flu
So their measures, which are designed to reduce community spread to random people in the community, workplace and schools, and increase household spread (which they assume to be close to 100% already) may have the opposite effect since community spread is close to zero, and household spread is likely 10% or less.
If someone else in your household gets infected they say nobody else in the house needs to continue beyond the end of the 14 day period but the person infected has to remain in the house. The assumption here again is that everyone else got it already.
If someone else does become ill during that period, their seven-day isolation starts that day. For example, it might run from day three to day 10 - when that person's isolation would then end. It would not restart if another member of the household fell ill
But anyone who fell ill on day 13 would see their seven-day isolation begin then - for their illness rather than to monitor for symptoms - meaning they would spend a total of 20 days at home
I have annotated the graphic from National Health England to show the issues with this approach, and why it might actually make things worse in the UK:
Text on graphic: This increases the risk of the original case infecting the others - this is the main way COVID-19 was transmitted in China.
About 80% of Chinese COVID-19 transmission is in households. For flu it is around 33%.
At 14 days: With flu typically all are infected by now anyway - which is why they say it doesn't matter to quarantine them all together
With COVID-19 on average none or one are infected - 3 to 10 out of 100 contacts get infected.
Anyone with COVID-19 is infectious for up to 14 days AFTER THEY GOT BETTER - this is how it spreads, hard to get but infectious for a very long time.
So, in short, because of their false analogy with ‘flu the government are telling people to stay at home and lock themselves up with their family for 14 days under the mistaken belief that if you have COVID-19 then the rest of your family already likely has it or will have it soon. The data from China shows that only 3–10% of them get it so this advice may well be encouraging spread and lead to our outbreak increasing faster than in other countries.
The UK policy may well reduce the amount of flu and colds but it might even increase the amount of COVID-19 infection.
The WHO recommend that if you do have COVID-19 that you can self isolate at home but anyone who is caring for you has to use a mask and know how to use it properly They say that you are potentially infectious for up to 14 days after you feel completely better and should have no visitors until that time period is up.
NHS - For COVID-19 (Suspected)
- Isolate for 7 days
- if in household all isolate for 14 days
- no need to use masks
- you can then leave - no need for test
WHO - test suspected cases
- If you have mild COVID-19, isolate until better
(you are still infectious) and no visitors- THEN isolate for an ADDITIONAL14 days
- patients and care givers must both use masks
- trace and isolate all close contacts for 14 days
The image is from here: Novel Coronavirus SARS-CoV-2
They can’t both be right.
This is the NHS advice:
Stay at home if you have coronavirus symptoms
Stay at home if you have either:
- a high temperature – this means you feel hot to touch on your chest or back (you do not need to measure your temperature)
- a new, continuous cough – this means coughing a lot for more than an hour, or 3 or more coughing episodes in 24 hours (if you usually have a cough, it may be worse than usual)
Do not go to a GP surgery, pharmacy or hospital.
This is the WHO advice:
Caring for infected people at home may put others in the same household at risk, so it’s critical that care-givers follow WHO’s guidance on how to provide care as safely as possible.
For example, both the patient and their care-giver should wear a medical mask when they are together in the same room.
The patient should sleep in a separate bedroom to others and use a different bathroom.
Assign one person to care for the patient, ideally someone who is in good health and has no underlying conditions.
The care-giver should wash their hands after any contact with the patient or their immediate environment.
People infected with COVID-19 can still infect others after they stop feeling sick, so these measures should continue for at least two weeks after symptoms disappear.
Visitors should not be allowed until the end of this period.
WHO Director-General's opening remarks at the media briefing on COVID-19 - 16 March 2020
Detailed advice here: Home care for patients with COVID-19 presenting with mild symptoms and management of their contacts
So, if you do have COVID-19 in its mild form and just got over it, you are actually, according to the WHO, still infectious for another two weeks. But in the UK, if you have some medical emergency (say, a broken ankle) after the original 7 days is up, you will go into a hospital and be treated by doctors and nurses who won’t take any precautions as they will believe you to be free of the virus.
The WHO advice is evidence based. It is based on data about how long the virus is infectious for based on transmission chains and case pairs. It is designed to completely stop any forward transmission of COVID-19 if you have it.
The NHS advice is based on this hypothetical influenza-like disease. It is not designed to protect you or your others completely from COVID-19 but to reduce the speed at which it spreads to others.
The UK's advice not to allow other family members or visitors into your houses may help. But then you have the issue of compliance with all this too. They assume only 75% compliance.
Over time, people will get bored and will stop doing this, especially when they know that most of them will be staying at home with a common cold or 'flu which is not COVID-19. After a few days of boredom, sitting at home, many will decide to go out and visit a friend at their home, or their neighbour.
They are much more motivated to follow instructions if they know they do have COVID-19. Such instructions can also be enforced by law for known cases and their contacts, as they were in the UK before this change to the "delay" phase.
As it is now someone will think
"I have a minute chance of having COVID-19 -most likely I have a cold or flu, the risk I pass it on is remote but unless everyone does this someone will"
That just doesn't have the emotional impact of
"I am confirmed to have COVID-19, if I visit my granddad he has a significant risk of dying of it"
So this advice will probably not even do much to reduce the visits of friends and relatives to old people or each other.
This is one of the most concerning aspects of their advice, it seems to me. The last thing we want is any measure that could increase the number of cases of this disease over the ones that there would be naturally.
skip to: Model needs to be updated to match COVID-19
Given the background of the last section (UK government assumes if one person in a household has COVID-190 most will get it - report says 10% or less), the NHS advice is not sufficient to keep COVID-19 out of the hospitals. At least, it isn't sufficient, if you see the WHO-China joint report as more reliable as a source for these issues than the UK's hypothetical flu model.
To take an example - after 7 days of self isolation, you feel better. Now you break an ankle. You just get someone to take you to hospital or call an ambulance, and you won’t say anything because you think you are fine. You don’t even tell them that you suspect that you have COVID-19 because you think you can no longer be infectious.
Now the doctors and nurses treat you just like anyone else. They won’t even wear surgical masks or eye protection.
This lead to several infections in hospitals in Wuhan before they started to take COVID-19 more seriously. Also - in Wuhan many of the infections were brought in from the public by the health workers. If the people they share a house with or their partner or relative may have it at home, but for the first week of this new policy, none of them were tested for it.
In these circumstances it is likely that some health care workers had it, and then thinking they were infection free,brought it in to work. Dr Bruce Aylward talks about all this here:
(click to watch on Youtube)
If your health system goes down you can't run your response early days of Ebola in West Africa it was one of the big big challenges we had and it's a common thing when emerging disease nobody knows It enters through the healthcare system remember that's where a virus is going to enter often because they come in looking for care and and all of a sudden boom it blows up
...
Most healthcare workers got infected in the community not in the health care system.
There had to be a two-pronged approach to this.
First was making sure that you run your COVID facilities safe and that was being addressed relatively early on but then that's your COVID hospital and this is your hospital for regular care.
So I'm pregnant don't feel great I'll go into the regular care hospital or I've had chest pain and I'm having difficulty breathing I'll go there and you go into the regular hospital and in fact you've got Covid and so a number of the ones that were happening were actually happening not in the covid facilities but they were happening in the regular facilities
So the first thing you always have to do in these is trying to figure out who's getting infected how are they getting infected where are they getting infected and then and then try and fix it and again everywhere we went this was a top priority
I don’t see how we can avoid hospital infections in the UK until we do the same. Do we have to learn all these lessons again from scratch? Do doctors, nurses and other patients have to die before they go back to following the WHO advice?
Meanwhile Public Health England have downgraded the protection that doctors have to wear for known COVID-19 patients - they now just need to wear a short gown or apron, and often without goggles. They have basically downgraded the protection required to the levels the WHO recommend for countries experiencing a shortage of personal protection equipment. The WHO say to resume the higher level of protection once supplies resume.
I give the details here:
Cannot protect health workers except by going back to contain phase
But it doesn’t make much difference now, since any doctor may be treating a patient with COVID-19 at any time and not know it. The mild cases of course are infected with the same virus as the more acute cases.
We have lost sight of where the virus is in our society with this policy. This risks COVID-19 spreading in hospitals to vulnerable patients, and through dentists and other heath care givers
We also risk it spreading to old people’s homes reaching them through their care givers, and prisons.
Professor John Ashton said recently on Question time:
The government have got predictions that if you get one serious case in a care home, you might finish with a mortality rate of 30%. They haven’t told anyone that. They have planning assumptions which they are not sharing with us.
There is no way to check independently if they do have such predictions, since as he says they have not shared their predictions with the public yet. But from the data for COVID-19 a 30% mortality rate could be possible in a care home with very elderly people who also have other conditions such as cardiovascular problems, underlying respiratory sickness, or diabetes.
skip to: The Imperial college London study
The assumptions are so different they urgently need to update their model with assumptions based on the real data from COVID-19. Once they do this, the predictions and recommendations are likely to change.
This can lead to a radically different outcome. For instance a change in the assumptions may make it possible to reduce the R0 number (average number of infections per patient) down to less than 1 and if that happens the disease soon stops completely.
Meanwhile we need to learn from the lessons of other countries, both the things that worked and the ones that didn’t, and build our policy on methods already proven to work.
By only delaying instead of stopping transmission, we have lost sight of where the virus is in society. We urgently need to find it again,
skip to: Example of Singapore shows genuine random community spread is rare
YThe Imperial College COVID-19 response team who advise the government say in the paper itself that their model was designed to model influenza originally. It is largely unchanged with minor modifications.
We modified an individual-based simulation model developed to support pandemic influenza planning to explore scenarios for COVID-19 in GB. The basic structure of the model remains as previously published. In brief,individuals reside in areas defined by high-resolution population density data. Contacts with other individuals in the population are made within the household, at school, in the workplace and in the wider community.
Paper Impact of non-pharmaceutical interventions (NPIs) to reduce COVID-19 mortality and healthcare demand
Popular exposition here: 3 charts that helped change coronavirus policy in the UK and US
Much of my information about COVID-19 for this section comes from this report:
This is cite number 16 of the Imperial college paper. However, unlike most scientific papers, there are no inline citations. I don’t see anything in the paper that matches what the WHO-China report says about COVID-19.
In the Imperial College London model:
Here is where they say this:
We modified an individual-based simulation model developed to support pandemic influenza planning to explore scenarios for COVID-19 in GB
With the parameterization above, approximately one third of transmission occurs in the household, one third in schools and workplaces and the remaining third in the community. These contact patterns reproduce those reported in social mixing surveys
...
Transmission events occur through contacts made between susceptible and infectious individuals in either the household, workplace, school or randomly in the community, with the latter depending on spatial distance between contacts.
Impact of non-pharmaceutical interventions (NPIs) to reduce COVID-19 mortality and healthcare demand
According to the big WHO-China joint report however
In China, human-to-human transmission of the COVID-19 virus is largely occurring in families. … Among 344 clusters involving 1308 cases (out of a total 1836 cases reported) in Guangdong Province and Sichuan Province, most clusters (78%-85%) have occurred in families … preliminary studies ongoing in Guangdong estimate the secondary attack rate in households ranges from 3-10%. Report of the WHO-China Joint Mission
"The Joint Mission learned that infected children have largely been identified through contact tracing in households of adults.Of note,people interviewed by the Joint Mission Team could not recall episodes in which transmission occurred from a child to an adult." Report of the WHO-China Joint Mission
[the WHO continue to say they don’t know the answer when asked in recent press briefings]
"There have been reports of COVID-19 transmission in prisons (Hubei, Shandong, and Zhejiang, China), hospitals (as above) and in a long-term living facility. The close proximity and contact among people in these settings and the potential for environmental contamination are important factors, which could amplify transmission."
This assumption of random transmission in the community might be one of the main reason for the difference in approach of the UK Government and the World Health Organization.
skip to: Asymptomatic spread
This is about the assumption:
randomly in the community, with the latter depending on spatial distance between contacts.
There may be some genuine community transmission of COVID-19 between random people who are unconnected, not airborne but through them coughing on each other. However there is so little of this that nearly all the cases in Singapore are connected through traceable links to previous cases, or come from outside of Singapore:
With influenza this random transmission is often through short distance airborne transmission. This is possible for influenza viruses particularly in crowded enclosed spaces.
But COVID-19 can't do that. See:
The random community spread figure, therefore, should be close to 0%. It is exactly 0% if that element is meant to model airborne spread.
You don't have to break every transmission chain to end an epidemic, just enough to reduce the numbers enough so that fewer are infected with each step of the transmission.
The difference between a third of it being community transmission, and close to 0% may seem minor, but if you are using contact tracing to stop an epidemic, this difference may be highly significant for projections and recommendations.
skip to: Period of infectiousness
In the Imperial College model also
Here is where they say these things:
We assume that symptomatic individuals are 50% more infectious than asymptomatic individual
We therefore assume that two-thirds of cases are sufficiently symptomatic to self-isolate (if required by policy) within 1 day of symptom onset, and a mean delay from onset of symptoms to hospitalisation of 5 days.
In the WHO - China report however,
Asymptomatic infection has been reported, but the majority of the relatively rare cases who are asymptomatic on the date of identification/report went on to develop disease. The proportion of truly asymptomatic infections is unclear but appears to be relatively rare and does not appear to be a major driver of transmission
If a third of the cases were asymptomatic with 50% of the infectivity of the symptomatic cases, this would surely have been noticed in Singapore and elsewhere.
About the only way to model this data with large numbers of asymptomatic cases would be if they have close to 0% of the infectivity of the symptomatic cases. Such cases only be detected later with serological surveys since they don't infect anyone else and so won't show up again as new case. To take an example, it is possible that large numbers of school children are infected, but the symptoms are so mild they don't infect anyone else, even other school children. This would lead to a larger iceberg of asymptomatic cases but would be of no consequence as regards strategies for controlling the pandemic. .
skip to: COVID-19 transmission data from South Korea
They have various other parameters that again don't seem to match known figures for COVID-19 but instead are based on previous experience with influenza.
According to the WHO
People infected with COVID-19 can still infect others after they stop feeling sick so these measures should continue for at least two weeks after symptoms disappear. Visitors should not be allowed until the end of this period. There are more details in WHO's guidance.
WHO Emergencies Press Conference on coronavirus disease outbreak - 20 March 2020.
skip to: Recommendations based on this fictional flu hypothesis
There are two forms of transmission that seem to be driving the spread. There is prolonged contact and there is brief but close contact. In both cases the main thing is the people concerned know each other, so you can do the contact tracing.
For example in South Korea with nearly 9000 cases in their bulletin as of 22nd March they say that epidemiological links have been found for 80.9% of the cases. That leaves 19.1% of the cases either under investigation or sporadic cases. Some of the ones where no contacts have been traced may turn out to just be untraced contacts of the new cases.
Individual provinces have values there varying up to 93.3% with epidemiological links for Chungnam - that's 112 out of 120 cases there that have epidemiological links South Korea is now down to 64 new cases, and 14 of those 64 are imported cases so only 50 new domestic cases on 22nd March.
I don't see how their theory can even begin to model what is happening in South Korea. You can't do it by supposing a vast iceberg of undetected infectious asymptomatic cases because they would infect someone with the more serious disease and these would show up as large numbers of people with no epidemiological links because they got it from someone who was asymptomatic. Also anyone who suspects they might have COVID-19 can go into their local screening center in South Korea and get tested.
Any person who suspect[s] onset of COVID-19 symptoms are advised to call the KCDC call center (1339) or local call centers (area code + 120), ask a local public health center, or visit a screening facility, before visiting a regular healthcare provider directly. All persons who visit a screening center should arrive wearing a mask and in their own car if possible, and disclose their international travel history to the healthcare professionals.
All this would be impossible with flu.
All these differences are why quarantine doesn't work by itself in their model, using their fictional disease - while in South Korea, Singapore, China etc, they are containing it with mainly quarantine and contact tracing.
They don’t model contact tracing and isolation of contacts, or isolation of individuals within a household, just quarantine of entire households which is not a strategy used by China because it would increase the household transmission rate.
Instead the objective was to isolate individual patients from other members of the household who don’t have COVID-19. Sometimes this was done at home but often they made make-shift new wards in stadiums and similar places for the mild cases as a way to isolate them.
Again this is not an intervention they modeled.
The contact tracing is part of the solution to end this. The WHO recommends that everyone does contact tracing. If they want to investigate this in a model they should model contact tracing and see how effective it is. The countries that do comprehensive contact tracing have had most success in stopping the spread.
skip to: What the WHO recommend
All of this has a major effect on their recommendations.
In their model the physical separation is just to slow down the spread. In the WHO recommendations, it is to break the chains of contact. The recommendations that our government is using come from the Imperial College paper:
With the second intervention where all household members stay at home for 14 days - notice that they comment in the recommendation itself that household contacts double.
In the guidance from the UK government they write:
it is likely that people living within a household will infect each other or be infected already. Staying at home for 14 days will greatly reduce the overall amount of infection the household could pass on to others in the community
Stay at home: guidance for households with possible coronavirus (COVID-19) infection
However though this is true for ‘flu, it is not true for COVID-19.
Household transmission studies are currently underway, but preliminary studies ongoing in Guangdong estimate the secondary attack rate in households ranges from 3-10%.
Between 1% and 5% of contacts were subsequently laboratory confirmed cases of COVID-19, depending on location .
So, between 3 and 10% of members in the same household get it, and between 1 and 5% of other close contacts.
Telling members of the same household to stay together indoors in a closed environment for 14 days seems likely to increase that secondary attack rate in households, though how far it would go above 10%, I doubt if anyone could model based on the data so far.
This is one of the main items of concern here I think - they may find that their policy is actually increasing the spread of COVID-19 because of their assumption that people in the same household have already infected each other.
This disease already doubles in numbers every 3–4 days and we don’t want to increase that.
Then look at the social distancing of the 70+ year olds. It increases household contacts by 25%. The other factor of contacts in the work place reduced by 75% is not going to do much. The reduction of the other contacts by 75% can help if they avoid things like family gatherings, religious events, visitors to old people’s homes etc.
But an increase in household contacts by 25% again increases the risk that the 70+ year olds get it from family members.
Also, the worst thing here is that their policies are likely to increase the spread to hospitals, because they are not identifying people as having COVID-19 if they get only the mild version.
skip to: Some of the main issues with the UK approach
THe WHO recommends to test everyone.
Anyone who doesn't have COVID-19 can do as they wish.
Anyone who does will need to be quarantined and all their contacts self isolate.
Typically there would only be one 1 COVID-19 patient in a household. But they can be cared for by other members. The WHO say that in that situation both the carer and the person cared for needs to wear surgical masks
The UK does have the ability to follow the WHO recommendation because it is what it did until they decided to change to this "delay" phase
With the WHO guidelines, contacts of a case self isolate for 14 days and if they are symptomless at the end of that time are then free to do what they like. If they do get a disease but not COVID-19 it's fine of course. But if they get COVID-19 then they also are quarantined in the same way as the original contact
The UK wouldn't have needed to do any of this if they had kept track of it all and the quarantine period is not long enough. After the 14 days COVID-19 patients are still infectious. And the problem also is that people will get bored and will stop doing this, especially when they know that most of the time it is not COVID-19
So this policy potentially can increase the risk of passing it on to others in the same household. Then 2 weeks later these people can leave and take it somewhere else.
I don't know if this will increase the spread but it's not clear whether it increases or decreases and I think it could be an increase.
skip to: This is a serious disease for many patients - and the health system
I think this needs more attention because this model is the basis of the UK policy for COVID-19.
They have not explained to us why we should be basing our policy on this hypothetical disease instead of the evidence based science of the WHO.
As far as I know most people in the UK are not aware that the UK has a different approach from the WHO.
The WHO say this with every recent press briefing.
WHO continues to recommend that isolating, testing and treating every suspected case, and tracing every contact, must be the backbone of the response in every country. This is the best hope of preventing widespread community transmission.WHO Director-General's opening remarks at the media briefing on COVID-19 - 18 March 2020
Their advice is based on a major WHO-China study led by Dr Aylward and Dr Liung with 25 experts, 13 from outside China and 12 from China. This team spent 9 days researching what the Chinese did and then laid down specific recommendations for both China and the world based on what worked and what didn’t work in China.
In more detail it involves isolating and testing every suspected case, quarantining every confirmed case, tracing every contact, isolating contacts for 14 days from the time of possible infection, and testing contacts during those 14 days to see if they become cases. Many countries are following this advice with success.
When the WHO declared COVID-19 a pandemic, Dr Tedros, Director General of the WHO said:
We are convinced that, although this is the first coronavirus to be labeled as pandemic proportion, at the same time we believe it will be the first also to be able to be contained or controlled.
Transcript for WHO Emergencies COVID-19 Press Conference, 11th March 2020
The WHO were responsible for overseeing the eradication of smallpox, also eradicating malaria from many countries and near eradication of polio. They have stopped many outbreaks of Ebola including one in the Congo that has been successfully stopped with no new cases now for a month. They respond to 200 or more epidemics every year. These people are absolute experts on this topic.
I think the UK people and the UK government need to be told clearly that their policy is based on a hypothetical variant of flu, that the WHO recommendations are based on measures that have been proven to work for COVID-19 and given the reasoning of the Imperial College team for why we should follow their approach instead of the approach of the WHO.
I think we also need to hear what the WHO recommend for the UK.
And I think we should have a proper debate - but with no delay. This has to be resolved quickly because if the Imperial College approach is mistaken, every day of delay not only costs lives but greatly increases the difficulty of ending the epidemic in the world, and not only that it increases the risk and difficulty in dealing with this pandemic for the rest of the world, especially those with weaker health care systems and countries with vulnerable populations such as malnourished children in refugee camps and people with AIDS in sub Saharan Africa.
If this is the wrong direction that the UK is headed on, we have no time for the luxury of experiment. We must stop this right NOW.
skip to: Devastating effect on doctors and nurses
Nearly everyone (80%) gets better within a couple of weeks.
The mild version is over in around a fortnight, sometimes only a couple of days. The severe version starts mild, but about a week in then you start to have difficulties breathing which means it is getting established in the lower parts of the lungs and you need medicine such as antivirals and monitoring. This is why it is important to seek professional care early rather than to try to self -treat breathlessness, because it is a sign of it getting established and they may be able to prevent it progressing further if they act fast (though this is not based on double blind clinical trials yet just "compassionate use" based on anecdotal observations)
It continues with needing oxygen to breathe and then if you are one of the unlucky ones you end up on a ventilator and the very worst affected find their lungs no longer work and need artificial lungs, after that then the immune system starts attacking their body and if they die it is of multi-organ failure.
Those who end up on ventilator may be on them for up to 6 weeks. When they recover, some have some loss of lung capacity and become breathless easily. Complete recovery of the most severe patients likely requires several months and things like swimming can help with healing the lungs. It's not known yet if there is any long term damage to the lungs in some patients.
From the data for the first 191 patients in Wuhan to get it, then for those early hospitalizations, from the start of the illness, it takes 4-9 days to start to feel breathless, 8 to 15 days for intensive care unit admission,12 to 19 days to need a ventilator and for the ones that died, 17 to 25 days to die.
The reason it causes so many issues for health systems is the high demand on ventilators and artificial lungs. The UK will soon need thousands of ventilators if our outbreak develops like the Italian one. We can buy those ventilators and train people to use them - but the big issue is the time element, to scale up to that many ventilators so fast.
If there is a shortage of ventilators then there's the tough decision, never before in an advanced health care system, that you may need to withdraw ventilator support from a patient who needs it but is not likely to survive, to give it to a more urgent case that can survive. A patient typically dies within minutes of withdrawing ventilator support.
See The Toughest Triage — Allocating Ventilators in a Pandemic
It's also the extra medical staff. Each ventilator needs two or three people monitoring the patients 24/7 and they need to wear personal protection equipment too.
As for ECMO machines, they are rare. Many hospitals don't have any. Normally these are used for 'flu patients to avoid damage to lungs. With COVID-19 the lungs don't get damaged in the same way and instead they are used when the amount of oxygen starts to get low. This makes it hard to know whether the ECMO is improving their chances or if they would have survived anyway. Jenelle Baduluk talks about the conundrum of how you decide whether someone needs ECMO or not here:
See Covid and ECMO – Who do we cannulate? with Jenelle Badulak"
skip to: Contact tracing has to be methodical and thorough
First, I am not saying this will happen. Long before we have 1000 doctors and 750 nurses die, the government will surely act to try to stop it. But it shows the scale of the problem we face which we urgently need to stop, sooner rather than later.
This is not theoretical. It has actually happened. Hubei has roughly the same population as the UK (Hubei: 58.5 million, UK:66.44 million) . For 12 days now, mild hospital cases have only been tested if they need overnight stay. In Hubei, 3000 health care workers got COVID19 and we are not taking the precautions they did.
In Italy, nearly 5000 health care workers have got the virus as of March 20th. As of 30th March, 63 Italian doctors have died so far. That includes 20 GPs, and 4 dentists, amongst others. You can read the list here (in Italian but you can read it in English with Google translate)
In Hubei they took many more precautions to protect their health workers. They took on 10,000 extra health care workers from around the world.
Here I am assuming half of them get infected. This seems likely as it seems bound to spread through most hospitals if nothing is done to protect our doctors, as sooner or later every hospital is going to treat a COVID-19 patient without knowing that they are, with current policy.
I am sure it will STOP long before we reach these figures, once we get the first few major hospital outbreaks. But it is then going to be hard work sterilizing all the hospitals and getting back to a clean COVID-19 free environment and segregating the patients and the doctors until it is all over.
For the older patients I am using the data for the first 1000 deaths in Italy and for under 50, data from China. For the sources see my: Deaths in Italy from Covid19 - similar to China - higher case fatality rate is due to more elderly patients affected
Total 1197
(I have rounded the numbers of doctors there to the nearest 500 in each group).
That makes it over 1000 doctors would die during the outbreak. I am using:
That would be more than ten doctors a day dying at the height of the outbreak.
There would be absolutely nothing to do about it since we need our doctors. You can close down sports matches but you can’t close down hospitals.
We would get many stories like this one of an Italian physician who continued treating COVID-19 positive patients although he knew his protection was inadequate due to running out of the right kinds of personal protection equipment:
Colleagues Mourn Italian 'Hero' Physician Killed by COVID-19
As I've already said, in the UK then the same doctor wouldn’t know if his patients were COVID19 positive - not if they came in for a broken ankle say. Or a dentist with a patient needing a tooth extracted. Or nurses including nurses caring for patients at home, or midwives (some pregnant women might be COVID19 +ve)
The nurses would be in a similar situation:
Total 752 nurses die.
Nurses, Midwives and Support staff by area, level, gender and age, January 2018 - NHS Digital
Of course with the disease spreading through hospitals, large numbers of patients in the hospitals will also die. It's the same for care homes as we already mentioned.
Then, a certain percentage of the doctors and nurses will need hospitalization. From US figures, about 20% of those who are infected need hospitalization (going from 14% at age 20-44 through to 30% at age 75-84.) and about 4.9% need intensive care (from 2% at age 20-44 through to 10% at age 75-84). It's hard to find good accurate data on this yet, I'm using the figures here, for a rough idea.
If anyone here knows of a proper study of this please say! I did that rough calculation because I can't find any study of the likely effects on the UK doctors and nurses.
I am not saying any of this will happen. When the first outbreaks are discovered in major hospitals, then just as happened with Wuhan our health service is sure to start taking a lot more care to protect its hospitals and health workers. This surely will also lead to them eventually increasing the quarantine period for doctors and nurses with mild versions of the disease at home, and testing patients for even mild versions of COVID-19 and taking far more care to prevent it entering the health system and upgrading the protection for doctors and nurses.
But we now surely have at least ten thousands of cases in the community, probably more. Hubei province has the same population as the UK approximately and they acted much sooner than us to stop it infecting their health care system but still had many problems with this.
skip to: Concerns about spread to populations with AIDS or malnourished children
The Chinese did that very thoroughly and methodically. They also did it in Singapore, and South Korea. With Italy I am not sure how thoroughly they are doing it - it is the most important part of the whole thing. It seems some areas are doing it more thoroughly than others. It is not the same as just isolating everyone in the same building. This virus is not airborne and others in the building are not at risk unless they are close or prolonged contacts with the patient with COVID-19.
It means that e.g. if they were staying over with a friend for a couple of nights - you phone up that friend and get them to self isolate, if they had an evening out with another friend you contact them and so on. It is straightforward stuff. Anyone can do it. Civil servants or volunteers can do it. You can re-use civil servants from other branches of government or local community organizations. You don't need to have any experience as health workers to do this.
But you have to be organized and methodical and thorough about it. This is not so hard with a dozen cases, but it gets much harder as it scales up unless you have good tools to track them all.
This process has to be very organized to keep track of, say, 100,000 contacts. Not just find them all, also to keep in touch with them all and get them tested as needed and retested. This was something the Chinese did with large databases and software and the West can learn from them how they achieved the co-ordination to get it working. Countries should be looking into how to do this before their outbreak starts.
One of the papers that may have influenced SAGE in their decision was "The Efficacy of Contact Tracing for the Containment of the 2019 Novel Coronavirus (COVID-19)."
This is one of the resource papers listed here: Scientific Advisory Group for Emergencies (SAGE): Coronavirus (COVID-19) response
They define "close contact" as being within 2 meters for 15 minutes or more
They then estimate that there would be an average of 36 individuals (between 0 and 182) to trace per contact and they say this is logistically challenging.
For contact tracing to be an effective public health measure requires secondary cases to be discovered before they become infectious; hence the time from the primary case becoming infectious to the tracing of their contacts needs to be shorter than the incubation period.
... Therefore, while contact tracing has the potential to control COVID-19 (and other close-contact pathogens) the ultimate success relies on the speed and efficacy with which suspect contacts can be contained.
"The Efficacy of Contact Tracing for the Containment of the 2019 Novel Coronavirus (COVID-19).
However - for COVID-19 then those infected remain infectious to others for a long time, through to two weeks after they have recovered from even mild symptoms. So, no, you don't have to find them before they become infectious to have a significant impact. The contact tracers look for all of a patient's contacts back to 14 days before the onset of symptoms if they don't know when an individual was infected.
The numbers that need to be traced are not far off, Singapore traced 6000 contacts for their first 243 cases which works out at 25 contacts per case, see:
Coronavirus: The detectives racing to contain the virus in Singapore
Singapore has released a new app which uses bluetooth to help keep track of who you are in proximity with automatically. This helps speed up contact tracing if you test positive.
Help speed up contact tracing with TraceTogether
South Korea has tested 300,000 people for 8,413 cases as of 18th March. Not all of those would be contacts but that makes a ratio of 36 tests to each case.
South Korea is reporting intimate details of COVID-19 cases: has it helped?
The Chinese though are the ones to trace most people so far. At the height of their epidemic they were tracing all the contacts of 70,000 people. Dr Bruce Aylward talks about it here (joint lead of the WHO-China joint mission)
(click to watch on Youtube)17:02 When it came to the response they had to manage massive amounts of data massive numbers of contacts because remember they're trying to find every case trace every contact of 70,000 cases across vast areas and know where they were follow that up so you manage all of that data and then you've got to be able to map that to other sources of data etc
20:01 finding and contact tracing - they did this in an extraordinary way with an extraordinary rigor of application and discipline and differentiated approach incredible collective action repurpose the machinery of government to make it work technologically powered and science driven and they applied that then to what was an escalating remember the exponential growth of the disease that you were seeing and remember every place that's hitting these days you're seeing exponential growth again ... we've got to tackle super fast to prevent a pandemic ... actually what China demonstrates is where this goes is within the control of our decisions to apply this kind of rigor and approach to to to this disease
It is a major challenge, sure. But nations are rising to it,and it being a challenge is not a reason to give up. It is a reason to innovate and rise to the challenge.
skip to: How can we get back on track?
Dr Tedros, director general of the WHO said much more in his speech on Monday 16th March reported as “test test test”. See my
He said that we all have a duty to stop this virus. He is especially concerned about what happens if it spreads to countries with people weakened by AIDS or with malnourished children or refugee camps.
Any country that doesn’t stop it becomes a source for it spreading more easily to those countries. Healthy children fight it off easily but the effects on malnourished children or young kids infected with AIDS are unknown. The WHO have previous experience of how devastating a respiratory disease can be for malnourished children in refugee camps.
We may well soon see scenes of malnourished children dying of this as well as people with their immune systems weakened with AIDS in countries where there is no possibility of getting ventilators for them all. We can prevent much of this future suffering for many people by acting promptly to slow down, and stop it in the UK.
As the virus moves to low-income countries, we're deeply concerned about the impact it could have among populations with high HIV prevalence, or among malnourished children.
WHO Director-General's opening remarks at the media briefing on COVID-19 - 16 March 2020
The WHO is acting to reinforce the ability of sub Saharan African countries to identify this virus rapidly, and stop it with diagnostic tests, personal protective equipment and training for their health workers. They have taken advantage of their existing response systems for other outbreaks, isolation wards for Ebola and anything they had available to prepare for the expected stress on their health systems of this virus if it gets there. Most sub Saharan African countries have been preparing for this disease with the greatest urgency for weeks now. It is a striking contrast to Europe.
Yet, despite all the African countries' efforts to prepare for this virus and the hundreds of millions of dollars in international donations to help them get ready, these countries are likely to struggle to contain this disease if it gets to them in large numbers.
This disease can easily get to sub Saharan Africa from the UK, which has strong historical ties with many African countries. South Africa already has a travel ban with the UK to try to stop us infecting them.
Previously UK residents didn’t even need a visa to travel to South Africa.
Now all UK residents require a visa to travel to South Africa, and the visa will automatically be declined, as for the other countries that the WHO classify as high risk including Iran, Italy, Germany and China.
skip to: Reactions to the UK announcement
We have to find our cases again.
Our recommendation from WHO was very, very clear; that all countries should be able to test all suspected cases. They cannot fight these pandemics blindfolded. They should know where the cases are and everything about the cases and that's how they can take decisions. WHO Emergencies Press Conference on coronavirus disease outbreak - 16 March 2020
Then we have to do everything, a comprehensive approach:
Our message to countries continues to be, you must take a comprehensive approach; not testing alone, not contact tracing alone, not quarantine alone, not social distancing alone; do it all.
Any country that looks at the experience of other countries with large epidemics and thinks, that won't happen to us, is making a deadly mistake. It can happen to any country. The experience of China, the Republic of Korea, Singapore and others clearly demonstrates that aggressive testing and contact tracing combined with social distancing measures and community mobilisation can prevent infections and save lives.
Japan is also demonstrating that a whole-of-government approach led by Prime Minister Abe himself supported by in-depth investigation of clusters is a critical step in reducing transmission. WHO has clear advice for governments, businesses and individuals; first prepare and be ready. Every person must know the signs and symptoms and how to protect themselves and others. Every health worker should be able to recognise this disease, provide care and know what to do with their patients.
Every health facility should be ready to cope with large numbers of patients and ensure the safety of staff and patients. Second, detect, protect and treat. You can't fight a virus if you don't know where it is. Find, isolate, test and treat every case to break the chains of transmission. Every case we find and treat limits the expansion of the disease.
WHO Emergencies Press Conference on coronavirus disease outbreak - 13 March 2020
The UK can do this. The diagnostic testing gap can be filled using rapid throughput machines. Mayo Clinic has just increased their testing capacity to 4000 per day using three such machines which they bought from Roche Diagnostics. With 75 machines, UK could increase throughput to 100,000 per day.
The WHO are planning to scale up their testing capacity 80 to 100 times.
If we look forward in this epidemic and we project ourselves forward a number of months and the amount of testing that's going to be needed, we need to scale that up approximately 80 to 100 times so it's not about doubling the availability of lab tests, it's not about trebling it. It's about potentially increasing that 80-fold. That's an extreme analysis but that's what we need to aim for and the director-general outlined the mechanisms by which we're going to achieve that, working with the public/private partnership and scaling up production and access to tests as they are needed.
WHO Emergencies Press Conference on coronavirus disease outbreak - 20 March 2020
The WHO say the reason some European countries give up on following their advice is not the lack of testing capacity - it is the contact tracing.
However anyone can do contact tracing including civil servants, and volunteers. It doesn’t require medical knowledge or health worker training.
For contact tracing you don't need a trained medical professional. You can accelerate and amplify the number of contact tracers almost instantly using other civil servants, using volunteers, using community organisations. Speaking with the Italian Government last night, they were going to very much use their community organisations to leverage improved contact tracing.
WHO Emergencies Press Conference on coronavirus disease outbreak - 11 March 2020
This is one section of my
I have expanded on it however with more details.
The UK can definitely do all this because it is what it did until they decided to change to this "delay" phase. It is an issue of scaling it up. Scaling up to trace so many contacts is a major challenge, involving the need of large databases and software to keep track of all the contacts,but other countries have shown it can be done.
The contacts self isolate for 14 days and if they are symptomless at the end of that time are then free to do what they like. If they do get a disease but not COVID-19 it's fine of course. But if they get COVID-19 then they also are quarantined in the same way as the original contact
skip to: How did this happen - paradigm shift?
When I heard that the UK was going to stop containing the disease and stop testing even mild cases, I was so shocked I could not believe my ears.
I had never heard of the Imperial College team research before then (the WHO never mention them in the press briefings).
As you can tell from this video, I was quite emotional about it at the time. I was so ashamed and so upset at my government’s decision. Cases were increasing fast in Europe but we were at last beginning to respond appropriately. And then this:
(click to watch on Youtube)
Others who have been following this, experts, not just science bloggers like me, have been equally upset and emotional about it. See for instance professor John Ashton, former president of the Faculty of Public Health and who is involved in working for the COVID-19 response team in Bahrain:
(click to watch on Youtube)
I don't know where to start really. I'm embarrassed by the situation in this country - this talk of four stages and that we're now moving on from the containment. We've lost the plot here. We haven't taken the action that we should have taken four or five weeks ago
Countries that took firm action at the time - you look what's happened in Hong Kong and Singapore which had a lot of cases initially but which took firm action and they've got the thing under control. We've lost control here.
We learned nothing from Ebola. In Ebola in 2014 we lost three or four months because we took a narrow science base to this and didn't understand the community aspects that related to the burial practices of folk in Sierra Leone.
And from another interview:
Well, I'm tearing my hair out, really, with this. I am very frustrated here. I am with Richard Horton, the editor of the Lancet and with Dr Tedros, Director General of the WHO. I think it was a kick up the bottom, particularly for this country. We have got a complacent attitude, it feels wooden, and academic, and we've wasted a month when we should have been engaging with the public. If this now spreads the way it looks like it is likely to spread, there will not be enough hospital beds and people will have to be nursed at home.
For more reactions immediately after the announcement see these tweets:
- Italian colleagues opinion is not translatable in polite way
Text on the image:
Devi Sridhar - Colleagues all think we are doing it wrong - Professor of global health, Edinburgh
Prof. Sunit K. Singh - Not ethical to make hunmans guinea pigs in name of "Herd Immunity" - Prof. and head of microbiology, BHU
James Smith - Italian colleagues opinion is not translatable in polite way - Vice principal and prof, Edin.
Martha - How do we learn about this disease and its transmission by only counting those in hospital? - BA (Hons). LLB. MSc.
[note for autistic readers -when Prof Singh talks about "human guinea pigs" it is hyperbole. He doesn't mean they are literally experimenting on us like guinea pigs. He means that the actions they are doing implementing an untested academic theory to deal with this outbreak, instead of the practical advice of the WHO, is like experimenting on guinea pigs in effect not in intention.]
The tweet itself is here:
Trying to explain the UK approach & objectives to colleagues in health security around the world & they all think we're doing it wrong. Do other governments think the same? If so we might be isolating the UK further when we actually need other countries' help more than ever.
— Devi Sridhar (@devisridhar) March 14, 2020
In case it goes out of sequence the replies to her tweet are here, by Professor James Smith, Prof Sunit K. Singh and Martha
The tweeters here are:
I listen to the WHO, then I listen to Dr Whitty and his team and it is as if they are describing different diseases.
So what was going on? I followed this up, read their paper, and to my utter astonishment, that seems to be exactly what is happening. They are modeling a hypothetical ‘flu that is very different from SARS - CoV2. This article is the result.
I am no expert on diseases or COVID-19 myself. All I am is a good science communicator who studied maths through to several years at postgraduate level. Papers such as this are easy for me to read and understand, and I know how to follow up cites and check them.
Other than that most of my understanding here comes from the WHO press briefings. I have watched all the briefings they have done on COVID-19 since they started on the 22nd January.
skip to: What should you do if you live in the UK ?
If you accept that this analysis is correct, then how could such a thing happen? I expect historians of science will be studying this example for decades and centuries to come. I have tried to understand how such a thing could happen. I think it is an issue of a paradigm shift, and of "trained incapacity" where their very expertise in influenza blinds them to the issues of matching their model to the real world data.
It is hard to understand but I don't think there is anything political here. Rather, it is that we don't have that background, that weight of learning and erudition that these modelers have and that has so impressed the UK government. When that happens it is hard to take on board new data that requires a complete paradigm shift in how to respond to an epidemic.
Bruce Aylward himself who was joint lead of the WHO-China team said he had never seen anything like it in his life - and he is a very experienced epidemiologist who lead the Polio eradication campaign of the WHO for many years. The received wisdom in his subject was that what the Chinese did is impossible.
He only really believed it on the ground when he saw the direct evidence in China that they had indeed done what they claimed to do.
I have a special interest in the history of Maths and this gives some nice examples of paradigm shifts. Back in Sumerian times then they put a mouth picture over a number, meaning “part” to turn e.g. the number 5 into 1/5
So the Sumerians could notate any number, e.g. 5 and a single part as a result of any number of divisions e.g. 1/5. However they had no way to notate, say, 3/5. For instance they couldn’t notate 3/4. Instead they had to notate it as
For centuries an entire civilization of people with the same genes as us, as intelligent as us, never invented the idea of a ratio. You can do the same calculations with these methods, but they become increasingly hard to do, with many more steps as the calculations get more complicated.
Ratios would have made many calculations they had to do so much simpler for them, but the idea never occurred to them. Not even their equivalent of our best scientists or mathematicians were able to think of this idea. Put Albert Einstein back into Sumerian times, raised as an orphan there, and he wouldn’t think of it either.
There are many other examples in maths. For instance, it took until the fifteenth century for negative numbers to take off in Europe. As late as 1758 the British mathematician Francis Maseres wrote that negative numbers
"... darken the very whole doctrines of the equations and make dark of the things which are in their nature excessively obvious and simple" .
That’s an example of a paradigm shift.
I hope this helps you have more sympathy for these experts. They are not stupid, or arrogant or unethical. Just facing a paradigm shift, and their vast experience of influenza has caused a “trained incapacity” that makes it really tough for them to change this paradigm. So they are discarding the evidence against their ideas over and over.
Their own erudition is the thing that is causing them problems. I am sure these people have scientific integrity. They will come around eventually. But we don’t have time for this; every doubling of cases makes it a longer and more difficult task to contain this and stop it - we must act promptly to stop it as fast as we can right now.
I talk about this in more detail here:
to Paradigm shifts and trained incapacity - why don’t the uk experts seem to see any of this?
skip to Do comment and share
If you actually get COVID-19 then yes the way to protect others is to stay in for 14 days after you feel better. But in the UK they won't test you so there is no way to know if you need to do that.
So there isn't much here that is actionable for us as individuals, unless we all stay off work for 3 -4 weeks every time we have a cold or the flu.
It is more for the government - they need to start testing people again and then quarantining people properly if they do have COVID-19.
What you can do though is to stop yourself getting it in the first place.
Do the hand washing / not touching face / keeping a distance from sick people - and nowadays they are saying in the UK to stay away from everyone.
Do that really rigorously and you'll be as safe as Bruce Aylward in Wuhan.
You can still get colds and 'flus because the instructions to protect yourself from COVID-19 don't necessarily work for them. SARS was airborne and I think some colds are too.
Also short distance airborne transmission is possible for influenza viruses particularly in crowded enclosed spaces. Seasonal influenza and influenza A(H1N1)
But COVID-19 can't do that. See:
The coronavirus COVID-19 is NOT AIRBORNE
So if you get occasional colds or 'flu then don't worry it doesn't mean you can get COVID-19 if you follow the advice properly.
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I hope that by writing this article I have helped to communicate the findings of the experts on COVID-19 and help spread awareness of why it is that the WHO say this can be controlled, and how they say we should do it.
Do comment with your thoughts on this.
Also do share with others you know including experts and politicians. This needs to be discussed widely and openly in the larger scientific community and in our political establishments.
Also please say if you spot any mistakes in this article however minor and I will fix them. Thanks!
If anyone reading this is an expert on any of this and notices anything I got wrong here, or have anything to add or correct please say in comments. And do share your thoughts on this. Thanks!
This is based on sections of my larger article here:
For the latest WHO press briefings go to
There is still much we can do and great hope. See
See also my
