Infectious disease experts are worried that the fastest-spreading COVID-19 subvariants yet -- the two latest versions of omicron -- could drive a new wave of infections.
The new highly-contagious omicron subvariants, BA.4 and BA.5, appear to evade protection from vaccines and previous infections more easily than any others before. They account for more than half of all COVID-19 cases in New England and more than 70% of infections across the U.S., according to recent data from the U.S. Centers for Disease Control and Prevention.
The subvariants could be even more wide-spread than what data shows, experts say, because most people are now either testing at home or not testing at all. Antibodies from vaccines and natural immunity from previous COVID infections do not seem to be preventing infection either, prompting new concerns of a potential summer COVID surge.
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Doctors have warned in recent weeks that BA.4 and BA.5 could result in another outbreak here in the near future, including a recent cautioning from White House COVID response coordinator Dr. Ashish Jha.
"Why has serious illness remained low? It's not random. It's from vaccinations and therapeutics that are widely available and easy to access," Jha wrote on Twitter Saturday. "But -- we're at a new inflection point. We could see current patterns continue, or we could see a new rise in infections and serious illness."
The Biden administration is now considering expanding the eligibility for second coronavirus boosters to adults under 50 in an effort to counter the contagious subvariants, the New York Times reported. The CDC currently recommends the second round of shots for immunocompromised people over the age of 50.
Meanwhile, Moderna announced it is developing two potential booster shots targeting the omicron subvariants, the Wall Street Journal reported, and could be rolled out by the fall. But Tufts Medical Center's Hospital Epidemiologist Dr. Shira Doron questioned whether variant-specific strains are the best approach in an interview on NBC10 Boston Monday.
"We know that the mRNA manufactures are looking to make a booster that contains BA.4 and BA.5, but by the time those vaccines are ready for distribution, we likely will have a new circulating subvariant," Doron said. "So only time will tell how successful the fall booster plan will be.”
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