The fast-changing coronavirus has spawned yet another super-infectious Omicron mutant, which is worrying scientists as it enters India and appears in many other countries, including the United States.
Scientists say the variant, called BA.2.75, can spread quickly and bypass immunity from vaccines and previous infection. It is unclear whether it can cause more serious disease than other Omicron variants, including the world-famous BA.5.
“It’s still very early to draw too many conclusions,” said Matthew Binniker, director of clinical virology at the Mayo Clinic in Rochester, Minnesota. “But it seems that, especially in India, the transmission rate is good from this exponential increase.” Whether it will surpass the BA.5, he said, remains to be determined.
Still, the fact that it has already been detected in many parts of the world even with lower levels of viral surveillance “is an early indication that it’s spreading,” said Shishi Luo, head of infectious diseases for Helix, a company that supplies viral sequencing information to the US Centers for Disease Control and Prevention.
The latest mutant has been spotted in several remote states in India and appears to be spreading faster than other variants there, said Lippi Thukral, a scientist at the Council for Scientific and Industrial Research-Institute of Genomics and Integrative Biology in New Delhi. It has also been found in about 10 other countries, including Australia, Germany, the United Kingdom and Canada. Two cases were recently identified on the US West Coast, and Helix identified a third case in the US last week.
Fueling experts’ concerns is a large number of mutations separating this new variant from Omicron’s predecessors. Some of these mutations are in regions that are associated with the spike protein and could allow the virus to bind to cells more efficiently, Binnicker said.
Another concern is that the genetic changes could make it easier for the virus to bypass antibodies — protective proteins produced by the body in response to a vaccine or infection from an earlier variant.
But experts say vaccines and boosters are still the best defense against severe COVID-19. In the fall, the US is likely to see updated formulations of the vaccine in development targeting newer Omicron strains.
“Some might say, ‘Well, vaccination and boosting haven’t stopped people from getting infected.’ And yes, that’s true,” he said. “But what we’ve seen is that the percentage of people who end up hospitalized and dying has declined significantly. As more people have been vaccinated, boosted or naturally infected, we are starting to see background levels of immunity worldwide rise.”
It may take several weeks to find out if Omicron’s latest mutant can affect the trajectory of the pandemic. Meanwhile, Dr. Gagandeep Kang, who studies viruses at India’s Christian Medical College in Vellore, said the growing concern about the variant underscores the need for more sustained efforts to track and trace viruses that combine genetic efforts with real-world information about who gets sick and how badly. “It’s important that monitoring is not a start-and-stop strategy,” she said.
Luo said BA.2.75 is another reminder that the coronavirus is constantly evolving and spreading.
“We would like to return to life before the pandemic, but we still have to be careful,” she said. “We have to accept that we live with a higher level of risk now than before.”
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Ghosal reported from New Delhi. Ungar reported from Louisville, Ky. The Associated Press Health and Science Division is supported by the Howard Hughes Medical Institute Division of Science Education. AP is solely responsible for all content.
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