The highly contagious Omicron subvariant BA.2, which is more transmissible and has caused new outbreaks in Europe and China, is now the dominant strain of Covid-19 in the United States, causing nearly 55% of all new Covid-19 infections last week, according to new data from the US Centers for Disease Control and Prevention (CDC).
The South and Mountain West are seeing the fewest cases in the US. BA.2 is causing slightly more than one-third of infections in those regions. But BA.2 has doubled as a result of circulating variants of the virus in the U.S. about every two weeks. At the beginning of February, the Omicron subvariant made up just 1% of sequenced Covid cases in the U.S. The hardest-hit region continues to be the Northeast, where BA.2 is causing more than 70% of all cases. In New England, BA.2 now makes up about 73% of all Covid cases, according to the CDC. In New York and New Jersey, BA.2 represents more than 70% of cases. Throughout the pandemic, the Northeast has often been an epicenter of new variants and a harbinger of what the rest of the nation will face.
The BA.2 subvariant also spreads about 75% faster than the earlier version of omicron, BA.1, according to the latest update from the U.K. Health Security Agency. BA.2 has caused a spike in infections in the U.K. and Germany in recent weeks, though cases have started to decline again there.
⚠️BA2 DOMINANT—Welp—CDC reports the #BA2 subvariant is now 54.9% of all cases as of March 26th. ➡️This matches our forecast of March 26th BA2 dominance **right on the nose**—for equilibrium plateau point. Wastewater plateaued too. Surge coming in April.
— Eric Feigl-Ding (@DrEricDing) March 29, 2022
Omicron and its subvariants generally result in less severe illness than the Delta variant. Though BA.2 spreads faster, it does not seem to make people sicker than the earlier version of omicron, according to data from South Africa and the U.K., among other countries.
Fauci on ABC is relatively optimistic about the BA.2 variant, says he doesn't think the US will see a major surge in cases and doesn't expect public health restrictions to be reimposed soon pic.twitter.com/0W0ouSYaPr
— Aaron Rupar (@atrupar) March 20, 2022
White House chief medical advisor Dr. Anthony Fauci said earlier this month that BA.2 could cause an uptick in cases in the U.S. But he does not expect another surge. Fauci said the country does not yet need to reintroduce Covid restrictions in response to the subvariant.