New strains of the fast-growing new COVID variant are spreading worldwide , stoking fears among health professionals of a potential wave of cases as the US and Europe head into the summer. The FLiRT strains, whose label is derived from the combination of the names of mutations in Omicron subvariants, have been rapidly spreading in the United States - where more than a third of coronavirus cases are coming from such strains. Among the strains include KP.

2, which accounts for 28.2 percent of COVID cases in the US as of May 11, according to the latest data by the Centers for Disease Control (CDC) . Fast-growing COVID variant delays vaccine update as FDA pushes back key meeting Here’s everything you need to know about the new Covid variant in the US KP.

2, now the dominant coronavirus variant in the country, has experienced a 24.4 percent uptick compared to the end of March, where only 3.8 percent of cases were recorded.

KP.1 - another FLiRT Variant - accounts for 7.1 percent of cases as of May 11, up from 1.

7 percent at the end of March. Both mutations are closely related descendants of its parental strain, the JN.1 variant, which have caused over 50 percent of infections prior to the end of March.

JN.1, once the dominant variant in the country, has underwent a 38.9 percent decrease of infections between early April and mid-May, when 15.

7 percent of cases have been reported so far. There is currently little evidence to indicate whether the FLiRT variants could cause more severe.