Safety of COVID-19 vaccine: A meta-analysis

Objective To systematically review the safety of different types of COVID-19 vaccines in the population. Methods Web of Science, PubMed, EMbase, The Cochrane Library, CNKI, WanFang Data and CBM databases were electronically searched to collect randomized controlled trials (RCTs) which reported safety of COVID-19 vaccines in population. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was then performed by using RevMan 5.4 software. Results A total of 5 RCTs involving 2 431 subjects were included. The results of the meta-analysis showed that COVID-19 vaccines developed more fever symptoms than placebo (RR=2.21, 95%CI 1.38 to 3.54, P=0.000 9). However, there was no significant difference in the incidence of adverse reactions (RR=1.28, 95%CI 0.96 to 1.70, P=0.10), injection site adverse reactions (RR=1.47, 95%CI 0.65 to 3.36, P=0.36) and systemic adverse reactions (RR=0.96, 95%CI 0.78 to 1.17, P=0.66) between two groups. Conclusions Current evidence shows that COVID-19 vaccines are sufficiently safe. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify the above conclusions. © 2021 West China University of Medical Science. All rights reserved.