Investigating the FLiRT variants of COVID-19: Is it an emerging concern?

The ongoing COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to multiple waves of infections globally. As the virus continues to evolve, new variants have emerged, some with concerning changes in transmissibility and virulence. Among these variants, the "FLiRT Variants" have recently gained attention due to their potential to alter the dynamics of transmission and disease severity. According to the Infectious Disease Society of America, the nickname ‘FLiRT’ is based on the technical names for their mutations. The FLiRT variants, particularly KP.2, seem to exhibit heightened transmissibility in comparison to earlier Omicron sub-variants. Additionally, they demonstrate a capacity to evade immunity conferred by prior infection and vaccines, although the full extent of this evasion is still being investigated. In this article, we review the characteristics of the FLiRT variants, including their genetic mutations, epidemiological features, potential impact on public health measures, and implications for vaccine efficacy. We also discuss strategies for surveillance, prevention, and mitigation efforts to control the spread of this variant and mitigate its impact on global health.