Epidemiological philosophy of pandemics

Tareef Fadhil Raham


Background: During  the COVID-19 pandemic, clinicians have struggled to understand why case fatality rates vary among countries. The role of clusters of infections in COVID-19 severity is well known before, furthermore the case overload was attributed to increased COVID-19 mortality in certain locations. The background theory in this study was the  already existing evidence that an increased viral load (density of infection) leads to more fatalities. The aim of this study was to find the correlation between high number of cases and high mortality (MR) in different countries and to find the correlation of MR with case fatality rate (CFR).

Methods: We chose thirty-one countries with testing coverage levels of >400,0000 tests/M and populations greater than 1 million inhabitants. We used ANOVA regression analyses to test the associations.

Results: There was a very highly significant correlation between MR and the total number of cases/million population inhabitants (M) (p=0.0000). The CRF changed with a change in the MR. A very high positive influence of the COVID-19 MR on the CFR (p= 0.0000).

Conclusions: Increased number of cases per million inhabitants is associated with increased MR. Increased MR is associated with increased CFR. These findings explain variable mortality rates in relation to CFR and to the number of cases/M. This evidence gives us an idea of the behavior of epidemics in general. This  will help in the development of infection control policies.


COVID-19, CFR, MR, Pandemic, Epidemic

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