Delhi clocks 246 dengue cases, double last year’s halfway count

New Delhi

There have been 246 cases of dengue till June 30 this year, according to Municipal Corporation of Delhi (MCD) data, which is more than double the number of cases, at 122, logged in the corresponding period in 2023.

In the preceding years, Delhi clocked 143 cases in the first six months of 2022, 36 cases in 2021 and 20 cases in 2020. Civic officials, however, said that despite the rise in the number of cases, there has been no dengue death so far this year.

A senior MCD official, who requested not to be named, said that with the instances of waterlogging reported across the city since the arrival of the monsoon last week, people should be more careful about curbing water accumulation in their homes and offices. “Source control is the best remedy to prevent the transmission of dengue. The strain of dengue has not been tested so far but citizens need to be more vigilant during monsoon,” the official said.

Dengue fever is caused by the Aedes aegypti mosquito, which breeds in stagnant water in spots like water storage drums, coolers, tyres, scrap and flower pots. Annual analysis of mosquito breeding site data from 2022 by the MCD showed that around 58.5% of Aedes aegyti larvae were found in water storage units, such as drums, buckets, and jerrycans, 30.2% in peri-domestic units, such as money plant vases, flower pots and bird pots, and overhead tanks accounting for 5.4%, sumps 2.1% and desert coolers 3.8%.

This year, MCD said it around 37,000 cases of mosquito breeding were recorded in the past six months in checks carried out by its workers. The civic body has issued around 40,000 challans and legal notices to owners of properties where breeding was found, for violating the Malaria and other Vector Borne Diseases Bye-Laws, 1975.

The civic body has also started drives to check 234 mosquito breeding hot spots, which were identified based on the high concentration of cases recorded in 2023.

A spokesperson for MCD said: “A meeting was convened by health minister on July 5 to review preparedness in wake of early arrival of monsoon. All the control measures are being taken, including house checks, awareness programmes, anti-larval measures, indoor spray, biological control and legal measures. Cases are sporadic, there are no hot spots currently.”

Aedes aegypti can spread dengue fever, chikungunya and yellow fever. It lays eggs in clean water and has adapted to breed among human dwellings.

In 2023, Delhi recorded 9,266 dengue cases and 19 deaths, which was the third worst outbreak of the viral infection in the city, according to MCD’s annual data. However, the severity of the outbreak was obscured as civic bodies held back weekly data. The civic body stopped issuing the weekly reports last year, ahead of the G20, and the process has not been resumed.

Atul Goyal, president of an umbrella body of RWAs (URJA), said that the MCD should ensure transparency in the matter of public health and people should be aware of the scale of the problem. “MCD should restart issuing the weekly reports. We are getting a lot of complaints regarding mosquitoes in RWA groups and the action is not translated on ground. We can see door-to-door campaigns (being undertaken), but fogging and fumigation drives have not started yet,” he said.

Improved surveillance

A second civic official said that the increase in case numbers is reflective of better surveillance and improvement in data gathering by the MCD after 2021 when dengue was declared a a notifiable disease. The Delhi government on October 14, 20211 issued a notification declaring the disease as “notifiable” under the Epidemic Diseases Act.

The notification made it mandatory for health care institutions to report cases to the health department to improve surveillance in the city.

“The notification has improved the reporting of cases, with number of hospitals reporting dengue cases, which is resulting in more number of cases,” the official said.

Civic officials said that before the notification under the Epidemic Diseases Act, only 35 large hospitals under sentinel surveillance system and a few larger private hospitals were reporting dengue cases. The number has currently increased to more than 900 big and small health care facilities, they said.