Emergence of Omicron BA.1 and BA.2 variants and concern over vaccine breakthrough infection.

ABSTRACT

The COVID-19 pandemic since 2020 created havoc across the globe. This led to the establishment of effective vaccines to mitigate the virus. Several vaccines are developed to create immunity amongst the population. However, due to emerging variants of SARS-CoV-2, despite a double dose of vaccines, people have still infected that termed vaccine breakthrough infection. This paper aims to highlight the recent re-surging massive outbreak of COVID-19 in China despite mass vaccination and, discuss the issue of vaccine breakthrough infection, possible causes, and recommendations to enhance immunity and curb the transmission.