Molecular and serological prevalence of Coronavirus in Chiropterans: A systematic review with meta-analysis

In recent years, and now especially with the arrival of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), there has been increased interest in understanding the role of bats in the dynamics of transmission and origin of this pandemic agent. To date, no systematic reviews have been published on this topic. This systematic review aimed to summarize and highlight the frequency of bat infections reported in currently available observational studies for coronavirus. The purpose of this study was also to examine the differences between the pool prevalence by technique and country. We performed a systematic literature review with meta-analysis, using three databases to assess coronavirus (CoV) infection in bats and its diagnosis by serological and molecular tests. We carried out random-effects model meta-analysis to calculate the pooled prevalence and 95% confidence interval (95% CI). In all, 824 articles were retrieved (1960-2021). After screening by abstract/title, 43 articles were selected for full-text assessment. Of these, 33 were finally included for qualitative and quantitative analyses. From the total of studies, the pool prevalence by RT-PCR (n=14,295 bats) for CoV was 9.8% (95% CI 8.7-10.9%); Italy reported the highest pooled prevalence (44.9%, 95% CI 31.6-58.1%), followed by the Philippines (29.6%). Regarding the ELISA, the pool prevalence for coronavirus from 15 studies, including 359 bats, was 30.2% (95% CI 14.7-45.6%). The results for coronaviruses with the MIF were significantly lower, 2.6% (95% CI 1.5-3.7%). A considerable proportion of infected bats tested positive, particularly by molecular tests. This essential condition highlights the relevance of bats and the need for future studies to detail their role as potential reservoirs of SARS-CoV-2. In this meta-analysis, bats were positive in almost 10% by RT-PCR, suggesting their relevance and the need to understand their potential participation in maintaining wild zoonotic transmission.