Fatality Rates After Infection With the Omicron Variant (B.1.1.529): How Deadly has it been? A Systematic Review and Meta-Analysis.

ABSTRACT

Background: Since late 2019, the global community has been gripped by the uncertainty surrounding the SARS-CoV-2 pandemic. In November 2021, the emergence of the Omicron variant in South Africa added a new dimension. This study aims to assess the disease's severity and determine the extent to which vaccinations contribute to reducing mortality rates. Methods: A systematic review and meta-analysis of the epidemiological implications of the omicron variant of SARS-CoV-2 were performed, incorporating an analysis of articles from November 2021that address mortality rates. Results: The analysis incorporated data from 3,214,869 patients infected with omicron, as presented in 270 articles. A total of 6,782 deaths from the virus were recorded (0.21%). In the analysed articles, the pooled mortality rate was 0.003 and the pooled in-house mortality rate was 0.036. Vaccination is an effective step in preventing death (odds ratio 0.391, p < 0.01). Conclusion: The mortality rates for the omicron variant are lower than for the preceding delta variant. mRNA vaccination affords secure and effective protection against severe disease and death from omicron.