The emerging challenge of FLiRT variants: KP.1.1 and KP.2 in the global pandemic landscape

Abstract

Abstract The SARS-CoV-2 virus has undergone substantial evolution, leading to emergence of new FLiRT variants characterized by specific spike mutations—F to L at position 456 and R to T at position 346—enhancing their transmissibility and immune evasion capabilities. Particularly, KP.2 shows a significant increase in cases in the USA, indicating a potential shift in the pandemic landscape due to its greater ability to evade vaccine-induced immunity and its higher effective reproduction number compared to JN.1. This evolving scenario underscores the need for continuous monitoring and adaptive response strategies to address the challenges posed by these new variants. This abstract examines the emergence of FLiRT variants KP.2 and KP1.1, descendants of the Omicron JN.1 variant, as they draw global attention amidst the ongoing coronavirus disease-2019 pandemic.