Doctor says FLiRT Covid spreads more easily, and could beat immunity

A doctor has explained why the new FLiRT variants of Covid have spread so quickly and rapidly become the dominant strain, saying their mutations could make them more infectious and more able to evade immunity from vaccines and previous infections. The new variants are descended from the Omicron family, but in a matter of weeks since they were first detected they have become the most common strains in the UK and the USA.

The latest figures from the UKHSA show a 17.9% increase in Covid infections week on week and a 32.6% increase in people admitted to hospital with the virus - while another 92 people have died. It comes as the most common strains now found in the UK are the FLiRT variants KP.2 and KP.1.1.

Dr Mary Ramsay, director of public health programmes at UKHSA, said: “Our latest data shows that Covid-19 cases are still rising."

She has urged everyone who is eligible to get a vaccine at nhs.uk/get-vaccine or call 119. The latest data from the USA shows that Covid carries a 35% higher risk of death than flu, based on deaths in hospitals last winter.

Dr Gregory P. Gasic, co-founder of VMeDx, said: "These strains are subvariants of JN.1.11.1, itself a descendant of JN.1. They contain mutations in the spike protein, which give them an advantage in terms of transmission and immune evasion. This makes them potentially more capable of spreading and evading immunity from prior infections or vaccinations.

"The reason these FLiRT variants have become dominant so quickly is due to their higher transmissibility. Specifically, KP.2 has outpaced other variants, accounting for over a quarter of infections in the US as of mid-May 2024. This has raised concerns about a potential surge in cases during the summer months. The ability of these new variants to evade immunity, even from recent boosters, adds an additional layer of concern, particularly for vulnerable populations like those over 65 or immunocompromised individuals.

"To combat these variants, staying current with vaccinations remains crucial. Updated vaccines and boosters are vital, even if their efficacy against these specific variants isn’t entirely clear. Public health guidelines, such as wearing masks, social distancing, and maintaining good hygiene practices, continue to be important measures to reduce the risk of infection. As always, it is essential to stay informed and follow the latest recommendations from health authorities. If symptomatic, getting tested and following isolation protocols can help prevent further spread."