The FLiRT variant, a group of new Covid-19 variants belonging to Omicron s JN.1 lineage, is rapidly spreading in the US. Variants KP.2 and KP 1.1, considered more infectious than previous Omicron variants, are causing concern. Experts warn of a potential new wave of infections in the summer. Symptoms of FLiRT remain similar to other variants. Vaccination and preventive measures are advised.