Case fatality rate of COVID-19: a systematic review and meta-analysis

OBJECTIVE: The ongoing novel coronavirus disease 2019 (COVID-19) is the leading cause of morbidity and mortality due to its contagious nature and absence of vaccine and treatment. Although numerous primary studies reported extremely variable case fatality rate (CFR) of COVID-19, no review study attempted to estimate the CFR of COVID-19. The current systematic review and meta-analysis were aimed to assess the pooled CFR of COVID-19. METHODS: Electronic databases: PubMed, Science Direct, Scopus, and Google Scholar were searched to retrieve the eligible primary studies that reported CFR of COVID-19. Keywords: (“COVID-19”OR “COVID-2019” OR “severe acute respiratory syndrome coronavirus 2”OR “severe acute respiratory syndrome coronavirus 2” OR “2019-nCoV” OR “SARS-CoV-2” OR “2019nCoV” OR ((“Wuhan” AND (“coronavirus” OR “coronavirus”)) AND (2019/12[PDAT] OR 2020[PDAT]))) AND (“mortality “OR “mortality” OR (“case” AND “fatality” AND “rate”) OR “case fatality rate”) were used as free text and MeSH term in searching process. A random-effects model was used to estimate the CFR in this study. I(2) statistics, Cochran’s Q test, and T(2) were used to assess the functional heterogeneity between included studies. RESULTS: The overall pooled CFR of COVID 19 was 10.0%(95% CI: 8.0-11.0); P < 0.001; I(2) = 99.7). The pooled CFR of COVID-19 in general population was 1.0% (95% CI: 1.0-3.0); P < 0.001; I(2) = 94.3), while in hospitalized patients was 13.0% (95% CI: 9.0-17.0); P < 0.001, I(2) = 95.6). The pooled CFR in patients admitted in intensive care unit (ICU) was 37.0% (95% CI: 24.0-51.0); P < 0.001, I(2) = 97.8) and in patients older than 50 years was 19.0% (95% CI: 13.0-24.0); P < 0.001; I(2) = 99.8). CONCLUSION: The present review results highlighted the need for transparency in testing and reporting policies and denominators used in CFR estimation. It is also necessary to report the case’s age, sex, and the comorbidity distribution of all patients, which essential in comparing the CFR among different segments of the population.