Detectability of the novel coronavirus (SARS-CoV-2) infection and rates of mortality from the novel coronavirus infection in different regions of the Russian Federation

TL;DR

This study analyzes how the detection rate of SARS-CoV-2 infections influences COVID-19 mortality rates across Russian regions, emphasizing the importance of increased testing and quarantine measures.

Contribution

It provides empirical evidence linking infection detectability with mortality rates and highlights regional disparities in testing practices within Russia.

Findings

Higher testing correlates with lower case-fatality ratios.

Regions with low detectability have higher COVID-19 mortality.

Enhanced testing and quarantine can reduce mortality.

Abstract

Relevance: Laboratory diagnosis of the novel coronavirus (SARS-CoV-2) infection combined with quarantine for contacts of infected individuals affects the spread of SARS-CoV-2 infection and levels of related mortality. Practices for testing for SARS-CoV-2 infection vary geographically in Russia. For example, in the city of St. Petersburg, where mortality rate for COVID-19 is the highest in the Russian Federation on Oct. 25, 2020, every death for COVID-19 corresponds to 15.7 detected cases of COVID-19 in the population, while the corresponding number for the whole of Russia is 58.1, suggesting limited detection of mild/moderate cases of COVID-19 in St. Petersburg. Methods: More active testing for SARS-CoV-2 results in lower case-fatality ratio (i.e. the proportion of detected COVID-19 cases among all cases of SARS-CoV-2 infection in the population). We used data on COVID-19 cases and deaths to examine the correlation between case-fatality ratios and rates of mortality for COVID-19 in different regions of the Russian Federation. Results: The correlation between case-fatality ratios and rates of mortality for COVID-19 in different regions of the Russian Federation on Oct. 25, 2020 is 0.64 (0.50,0.75). For several regions of the Russian Federation, detectability of SARS-CoV-2 infection is relatively low, while rates of mortality for COVID-19 are relatively high. Conclusions: Detectability of the SARS-CoV-2 infection is one of the factors that affects the levels of mortality from COVID-19. To increase detectability, one ought to test all individuals with respiratory symptoms seeking medical care for SARS-CoV-2 infection, and to undertake additional measures to increase the volume of testing for SARS-CoV-2. Such measures, in combination with quarantine for infected cases and their close contacts help to mitigate the spread of the SARS-CoV-2 infection and diminish the related mortality.