Since the start of the pandemic more than two years ago, sudden increases in COVID-19 cases have been driven by the emergence of new variants, including delta and omicron. Currently, a more contagious omicron subvariant, called BA.5, accounts for most new cases in the United States, but a distinct, newer subvariant is gaining attention.
Known as BA.2.75, the subvariant may be able to evade immunity from vaccines and previous infections, the scientists say. The strain includes multiple mutations in the gene encoding the virus’ spike protein, which allow the virus to bind more efficiently to the host cell’s receptor, explained Dr. Matthew Binnicker, director of Mayo’s Clinical Virology Laboratory. Clinic, in an article. .
Detected in India in May, the strain appears to be spreading faster than other subvariants there and is being monitored by both the World Health Organization and the Centers for Disease Control and Prevention. Cases have surfaced in at least a dozen countries, including the United States, where numbers remain extremely low.
A total of 13 cases have been confirmed in the United States, including three in Illinois, said Dr. Allison Arwady, commissioner of the Chicago Department of Public Health.
At this point, it doesn’t look like the strain will lead to another major wave of COVID in the United States, but the possibility remains.
“…We’re keeping an eye on it,” Arwady said. “We’re doing a good job of testing and looking forward to it here, which is one of the reasons we might find it [BA.2.75].”
BA.2.75 spreads more efficiently from person to person, according to Binnicker, who explained that there is no solid data to show that it causes more severe disease compared to other subvariants. . However, as more people become infected, the chances of the virus infecting a more susceptible person increases.
“…Those with an immunocompromised condition could still end up with serious illness and be hospitalized,” he explained. which is very likely to have worse outcomes then increases. »
The threat of the BA.2.75 variant in India underscores the importance of global vaccination, Dr. Sabrina Assoumou, a physician at Boston Medical Center, told NBC Boston.
“We’re not going to be able to overcome this pandemic if we don’t make sure everyone, everywhere is safe,” she said.
India’s population has a different immunity from that of the United States, several doctors in Boston said, because different vaccines were given at different times and different variants circulated at different times. These variables result in fluctuating levels of infection-induced immunity.
“We can’t assume what happens there will happen here, and yet we have to prepare for surges. We’re still preparing for surges now,” said Dr Shira Doron, of Tufts Medical Center. “Variants will emerge that will evade immunity from the vaccine and prior infection, and we can never know exactly what they will do to our case rates until we get there.”
As the school year approaches and new variants including BA.2.75 lead to additional cases, monitoring the number of infections will be crucial.
“There is certainly a concern that as we move into the fall and winter months of 2022 and then into 2023 that new strains of the virus, including BA.27.5, will increase as children go back to school,” Binnicker said. “They will interact and there will be an increased rate of transmission of viruses, including COVID 19.”