New Covid FLiRT variants raise concerns over summer peak

LONDON — New strains of Covid-19 are spreading around the world, sparking concerns among health professionals about a possible spike in cases this summer, four and a half years after the pandemic began.

FLiRT variants — whose label derives from the names of mutations in the variants’ genetic code — are on the rise in the United States and Europe as the coronavirus continues to mutate from earlier strains.

The new group descends from the previously dominant JN.1 variant, an omicron offshoot. There is currently little evidence that the new strains are more serious, but they appear to have independently detected the same set of mutations, according to the John Hopkins Bloomberg School of Public Health.

KP.2 is now the dominant strain in the United States, according to the latest data from the Centers for Disease Control and Prevention. The strain accounted for 28.2% of all cases in the two weeks to May 11, up from 3.8% in late March, shortly after it was first discovered.

Cases of KP.1.1, another FLiRT variant, have also increased to account for 7.1% of current infections, the agency said.

In Europe too, cases have increased, with the new variant now detected in 14 countries.

The World Health Organization, in its latest update earlier this month, said cases remained limited in all reporting countries. However, some countries show “a slight increase in detections from very low levels”.

Last week, the UK Health Security Agency said it was continuing to monitor data on new variants in the UK and internationally, assessing their severity and the continued effectiveness of vaccines. “There are no changes to the broader public health advice at this time,” the agency said in an update.

It currently appears unlikely that the new strains will cause a major wave of infections as has been the case in the past when public immunity was lower, said Jennifer Horney, a professor of epidemiology at the University of Delaware . But she noted that the new strains would likely lead to an increase in cases over the coming summer months.

“Although our idea of ​​what a wave of COVID-19 infections looks like has changed over the course of the pandemic, it is likely that these new strains will lead to an increase in the number of cases in the United States in the coming months ” Horney said. told CNBC via email.

“Many will be mild, based on our existing immunity and not changes in the circulating strain,” she said.

However, health professionals will closely monitor the effectiveness of current vaccines against the new strains.

Next month, the US Food and Drug Administration’s vaccine advisory committee will meet to discuss recommendations for mixing variants for this winter’s Covid-19 vaccine, after postponing an earlier discussion aimed at collecting more data.