https://orcid.org/0000-0002-5902-2525
To the Editor—We read with great interest the results of the analysis by Harteloh et al [1], who concluded that the death rate in The Netherlands from the 1918–1920 Spanish flu was more than twice as high as the death rate for coronavirus disease 2019 (COVID-19) in 2020–2022 (ie, 214 vs 98 per 100 000 per year exposure). This is not surprising as the pathogen responsible for the Spanish flu pandemic (ie, influenza virus A/H1N1) was very aggressive, hit a nearly naive population with no prior immunity, and evolved at a time when healthcare and economic resources were extremely limited compared to recent times. To determine whether similar evidence could be replicated in other countries, we used statistics on the total resident population and the number of deaths from the Spanish flu in 1918–1920 [2] and from COVID-19 in 2020 [3] (ie, before the introduction of COVID-19 vaccination at the end of December 2020) in Italy.
The results of our analysis are shown in Figure 1. The Spanish flu affected a total Italian population of 36.280 million people and caused 390 000 deaths (crude death rate: 10.7 × 1000 inhabitants), while COVID-19 affected an Italian population of 59.236 million people and caused 77 165 deaths during the first year (crude death rate: 1.3 × 1000 inhabitants). Thus, the risk of dying from Spanish flu was >8 times higher than the risk of dying from COVID-19 before the nationwide rollout of COVID-19 vaccination began (odds ratio, 8.33 [95% confidence interval, 8.27–8.40]; P < .001). A disproportionate evidence was found after dividing mortality during Spanish flu and COVID-19 into three age groups, namely 1621 vs. 2 ×100 000 in the 0–49 years age group, 461 vs. 50 ×100 000 in the 50–69 years age group, and was instead similar (573 vs. 525 ×100 000) in the 70 years or older age group, reflecting the data reported by Harteloh et al.
Crude death rate in Italy for the Spanish flu pandemic (2018–1920) and coronavirus disease 2019 (COVID-19) before the initiation of the nationwide COVID-19 vaccination campaign.
Overall, our analysis confirms that the Spanish flu pandemic was certainly more deadly than the pandemic caused by severe acute respiratory syndrome coronavirus 2, although the death rate in Italy before vaccination began for both pathologies was significantly higher than that reported by Harteloh et al in The Netherlands [1].
Notes
Ethics statement. There were no living persons involved in this study. According to Dutch Civil Law (Article 7: 458) no ethical approval is required for a secondary analysis on nonidentifiable data of deceased persons.
Disclaimer. The opinions expressed in this article are of the authors and do not necessarily represent the views of Statistics Netherlands.
References
Italian National Institute for Statistics. Impact of the COVID-19 epidemic on the total mortality of the resident population—years 2020–2021 and January 2022 [in Italian]. 2022. https://www.istat.it/it/archivio/266865. Accessed 9 February 2024.
Author notes
Potential conflicts of interest. The authors: No reported conflicts.
Both authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
