Association of Country-wide Coronavirus Mortality with Demographics, Testing, Lockdowns, and Public Wearing of Masks

Abstract

We studied sources of variation between countries in per-capita mortality from COVID-19 (caused by the SARS-CoV-2 virus). Potential predictors of per-capita coronavirus-related mortality in 200 countries by May 9, 2020 were examined, including age, gender, obesity prevalence, temperature, urbanization, smoking, duration of the outbreak, lockdowns, viral testing, contact-tracing policies, and public mask-wearing norms and policies. Multivariable linear regression analysis was performed. In univariate analysis, the prevalence of smoking, per-capita gross domestic product, urbanization, and colder average country temperature was positively associated with coronavirus-related mortality. In a multivariable analysis of 196 countries, the duration of the outbreak in the country, and the proportion of the population aged 60 years or older were positively associated with per-capita mortality, whereas duration of mask-wearing by the public was negatively associated with mortality (all P < 0.001). Obesity and less stringent international travel restrictions were independently associated with mortality in a model which controlled for testing policy. Viral testing policies and levels were not associated with mortality. Internal lockdown was associated with a nonsignificant 2.4% reduction in mortality each week (P = 0.83). The association of contact-tracing policy with mortality was not statistically significant (P = 0.06). In countries with cultural norms or government policies supporting public mask-wearing, per-capita coronavirus mortality increased on average by just 16.2% each week, as compared with 61.9% each week in remaining countries. Societal norms and government policies supporting the wearing of masks by the public, as well as international travel controls, are independently associated with lower per-capita mortality from COVID-19.

Face Masks Against COVID-19: An Evidence Review

“…Their models estimated that 80-90% masking would eventually eliminate the disease. They also looked at an empirical dataset, similar to those of Leffler et al and Goldman Sachs (31,34), finding a very strong correlation between early universal masking and successful suppression of daily case growth rates and/or reduction from peak daily case growth rates, as predicted by their theoretical simulations.…”

“…There are now over 100 countries that have implemented mask requirements (31), and many regions such as US states that have their own mask mandates. Most of these requirements were instituted after there was a shortage of medical masks, so results in these countries are likely to reflect the reality of what masks the public is able to access in practice during a pandemic.…”

“…The same approach is now being used in many jurisdictions to increase mask wearing compliance, by mandating mask use in a variety of settings (such as public transportation or grocery stores or even at all times outside the home). Population analysis suggests that these laws are effective at increasing compliance and slowing the spread of COVID-19 (31,33,34). C. Additional benefits for concurrent epidemics.…”

Uniting Infectious Disease and Physical Science Principles on the Importance of Face Masks for COVID-19

“…However, mask wearing prevalence in the U.S. has been variable across regions of the country, compared to 95% adherence in countries where cultural norms or mandates facilitated the practice. 1 In the U.S., there has not yet been a federal mask mandate, although individual counties and states have successively (but not uniformly) instituted individual mandates.…”

Masks and Face Coverings for the Lay Public

“…An observational study comparing 34 regions of Ontario, Canada, which introduced mask mandates on different dates, found that in the weeks after implementation, such mandates were associated with 25% fewer new cases of COVID-19 per week ( 46 ). In a study across 200 countries, in those with cultural norms or government policies supporting public masking, per capita mortality from COVID-19 increased by 16.2% per week, compared with 61.9% per week in the remaining countries ( 47 ).…”