From Wuhan to Omicron K.P2 strain: A comprehensive review of SARS-CoV-2 phylogeny and public health implications of the latest booster vaccine

Abstract

The SARS-CoV-2 virus continues to evolve, with the Omicron KP.2 variant, a descendant of BA.2.86, emerging as a public health concern due to its rapid spread and resistance to existing immunity. This review examines the phylogenetic evolution of SARS-CoV-2, focusing on KP.2 and its key mutations (R346T, F456L, V1104L), alongside its epidemiological implications. It also discusses the development and approval of the KP.2-adapted booster vaccine, shown in clinical trials to significantly enhance immune responses and protect against symptomatic and severe disease, particularly in vulnerable groups. Despite vaccine advancements, challenges in global distribution and inequity persist, especially in low- and middle-income countries, increasing the risk of vaccine-resistant variants. The manuscript underscores the importance of equitable access to the KP.2-adapted booster to control the pandemic and prevent future outbreaks, while highlighting the need for continuous surveillance and broader-spectrum vaccine research as the virus evolves.

Keywords: COVID-19 booster vaccine; Omicron KP.2; SARS-CoV-2 variants; immune evasion; vaccine equity; viral mutations.