Global variation of COVID-19 mortality rates in the initial phase

다국어 초록 (Multilingual Abstract)

Objectives: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused devastation in over 200 countries. Italy, Spain, and the United States (US) were most severely affected by the first wave of the pandemic. The reasons why some countries were more strongly affected than others remain unknown. We identified the most-affected and less-affected countries and states and explored environmental, host, and infrastructure risk factors that may explain differences in the SARS-CoV-2 mortality burden.
Methods: We identified the top 10 countries/US states with the highest deaths per population until May 2020. For each of these 10 case countries/states, we identified 6 control countries/states with a similar population size and at least 3 times fewer deaths per population. We extracted data for 30 risk factors from publicly available, trusted sources. We compared case and control countries/states using the non-parametric Wilcoxon rank-sum test, and conducted a secondary cluster analysis to explore the relationship between the number of cases per population and the number of deaths per population using a scalable EM (expectation–maximization) clustering algorithm.
Results: Statistically significant differences were found in 16 of 30 investigated risk factors, the most important of which were temperature, neonatal and under-5 mortality rates, the percentage of under-5 deaths due to acute respiratory infections (ARIs) and diarrhea, and tuberculosis incidence (p < 0.05) Conclusion: Countries with a higher burden of baseline pediatric mortality rates, higher pediatric mortality from preventable diseases like diarrhea and ARI, and higher tuberculosis incidence had lower rates of coronavirus disease 2019-associated mortality, supporting the hygiene hypothesis.

참고문헌 (Reference)

1 Netea MG, "Trained immunity : a tool for reducing susceptibility to and the se¬verity of SARS-CoV-2 infection" 181 : 969-977, 2020

2 Zeberg H, "The major genetic risk factor for severe COVID-19 is inherited from Neanderthals" 587 : 610-612, 2020

3 Stiemsma LT, "The hygiene hypothesis : current perspectives and future therapies" 4 : 143-157, 2015

4 COVID-19 Host Genetics Initiative, "The COVID-19 Host Genetics Ini¬tiative, a global initiative to elucidate the role of host genetic factors in susceptibility and severity of the SARS-CoV-2 virus pandemic" 28 : 715-718, 2020

5 Welliver RC Sr, "Temperature, humidity, and ultraviolet B radiation predict community respiratory syncytial virus activity" 26 (26): S29-S35, 2007

6 Corburn J, "Slum health : arresting COVID-19 and improving well-being in urban informal settlements" 97 : 348-357, 2020

7 Kontis V, "Magnitude, demographics and dy¬namics of the effect of the first wave of the COVID-19 pandemic on all-cause mortality in 21 industrialized countries" 26 : 1919-1928, 2020

8 Kovacic D, "Immunological principles by which the tuberculosis BCG vaccine may possibly reduce SARS-CoV2-related morbidity and mortality in vaccinated patients: a case for BCG vaccination during the COVID-19 pandemic" Research Gate

9 Severe Covid-19 GWAS Group, "Ge¬nomewide association study of severe Covid-19 with respiratory fail¬ure" 383 : 1522-1534, 2020

10 Islam MR, "Genome-wide analysis of SARS-CoV-2 virus strains circulating worldwide implicates hetero¬geneity" 10 : 14004-, 2020

11 Miller A, "Correlation between uni¬versal BCG vaccination policy and reduced morbidity and mortality for COVID-19: an epidemiological study"

12 Roser M, "Coronavirus pandemic (COVID-19)" Our World in Data

13 World Health Organization, "Coronavirus disease (COVID-19) weekly epidemiological update and weekly operational update" WHO

14 Ritchie H, "Coronavirus (COVID-19) deaths" Our World in Data

15 Ritchie H, "Coronavirus (COVID-19) cases" Our World in Data

16 Escobar LE, "BCG vaccine protection from severe coronavirus disease 2019(COVID-19)" 117 : 17720-17726, 2020