People across at least 10 states have now been infected by BA.2.86, a highly mutated variant of the virus that causes COVID-19, which the authorities have been following closely.
According to data calculated from the global virus database GISAID, laboratories have reported finding BA.2.86 in samples from Colorado, Maryland, Michigan, New York, Ohio, Oregon, Pennsylvania, Texas, Virginia and Washington.
Estimates suggest that BA.2.86 is still a small proportion of new COVID-19 cases nationwide.
Too few sequences of the virus have been reported to appear on the Centers for Disease Control and Prevention’s second-week variant discretionwhich still shows that a large number of closely related XBB variant descendants are driving virtually all infections around the country.
“The diversity is less than it appears. Many of these lineages actually have identical spike sequences. We’ve observed this before, where we see convergent evolution and viruses evolve to have the same substitutions,” said Natalie Thornburg, a laboratory department manager in CDC’s Division of Coronavirus and Other Respiratory Viruses.
Thornburg, who spoke at a meet of the agency’s vaccine advisers last week, said it was still too early to know “whether BA.2.86 will be of any significant circulation.”
Health officials believe BA.2.86 continues to spread widely around the world after scientists first raised concerns in August over the strain’s large number of mutations.
“We conclude this because some of the people infected with BA.2.86 have no known connections to other infected individuals and did not recently travel to an area with known cases of illness from BA.2.86,” the CDC said Friday. in a risk assessment.
More countries have reported finding the variant in either sewage samples or tests from people who are infected, including provinces in Canada. CDCs airport test program have also picked up signs of the strain of arriving travelers from abroad.
While it’s too early to say how transmissible the strain might be compared to other strains on the rise, officials say BA.2.86 has so far proven to have the ability to cause outbreaks.
Nearly two dozen nursing home residents were infected with the BA.2.86 variant in a cluster of the cases at the end of last month, officials in the United Kingdom reported.
“At this point, although we have limited clinical data on the cases that have been reported, there is no evidence that it causes more severe disease. But it is something we will continue to track,” Hanna Kirking, from the CDC’s COVID-19 epidemiology task force, said Thursday at event hosted by the Infectious Diseases Society of America.
Could BA.2.86 ride a new wave this winter?
The CDC has described early research findings as “calming” about the variant so far, suggesting that it may not be as able to evade the body’s immune system as originally feared.
Vaccine manufacturers have too said their data suggest updated COVID-19 shots now is rolled out should also work against BA.2.86.
Research into BA.2.86 has thus far largely relied on pseudoviruses, which are other viruses that have been mocked up in a laboratory to mimic BA.2.86’s characteristic mutations. Better results will have to use viruses grown from actual samples of infected patients, a process now underway.
“CDC has generated two authentic isolates of BA.2.86. One confirmed and one suspected. We are in the process of distributing BA.2.86 virus to multiple laboratories to do transmission studies, multiple neutralization studies, against many different kinds of sera,” Thornburg said .
So far, officials have expressed “guarded hope” for signs of the current late summer wave of COVID-19 driven by other variants has passed its peak. One leading indicator of the virus – emergency room visits – have been falling in recent weeks.
Recent years have seen renewed increases in the virus returning in the colder months influenza and RSVor respiratory syncytial virus. The CDC says it’s too early to tell how the BA.2.8 variant will fare its modeling for the upcoming respiratory virus season.
Meanwhile, scientists have already tracked BA.2.86, which is beginning to evolve into at least two different branches. Cases from both subgenera have been seen in the United States so far, among the handful of cases reported globally so far.
“That’s probably the tip of the iceberg, as we know we don’t have complete sequencing coverage,” Kirking said.