A new omicron subvariant, BA.2.12.1, is taking hold in the U.S. and was the second-most widely spread form of the coronavirus last week, according to a report published Tuesday by the Centers for Disease Control and Prevention.
BA.2.12.1 made up 19% of total U.S. cases the week ending April 16, increasing its spread by almost 67% from the week before. The CDC says omicron variants overall cause less-severe illness, although they spread faster than previous variants like delta.
Mutations in COVID variants are allowing the virus to dodge protection offered by vaccines in some cases, Andy Pekosz, a professor at the Johns Hopkins Bloomberg School of Public Health, told CNN.
“What we really just don’t know right now is how much those mutations are going to be contributing to increased spread or increased disease severity,” Pekosz said.
The New York Department of Health said last week that the subvariants BA.2.12.1 and BA.2.12 accounted for over 80% of cases in the state, and said both were more transmissible than BA.2 with a “23% – 27% growth advantage.”
The BA.2 variant was still causing the majority of infections in the U.S., accounting for 74% of total cases from April 10 to April 16, the CDC said. That percentage fell slightly from the previous week, when BA.2 made up 75.5% of the total.
Against the backdrop of rising new variants, the Biden administration is scrambling to provide new guidance around masks after a federal judge in Florida struck down a federal mask mandate for air travel and other forms of public transportation.
White House press secretary Jen Psaki said the judge’s ruling was a “disappointing decision.”
At the same time, President Joe Biden and his administration have signaled that people will have to make their own decisions on COVID as the pandemic evolves. Biden on Tuesday told reporters it’s up to Americans to decide whether to mask up aboard airplanes.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said last week that COVID won’t disappear and that people will have to weigh individual risks as cases rise.
Dr. Ashish Jha, the White House COVID-19 response coordinator, said he would continue to follow CDC guidance and mask up on planes.
Meanwhile, the Department of Justice is weighing an appeal to the court ruling if the CDC determines the mask mandate should be extended beyond its intended expiration on May 3.