New COVID Variant May Be Less Threatening Than First Feared
TUESDAY, Sept. 5, 2023 (HealthDay News) – When new COVID variant BA.2.86 emerged in late July, scientists had concerns about its ability to evade immunity. But early lab tests seem to be easing those fears, as well as concerns over the variant's ability to spread widely.
Also called Pirola, the variant is highly mutated, with more than 30 changes to its spike protein compared to its close ancestor BA.2 and to XBB.1.5, CNN reported. That big leap in evolution is similar to what happened when Omicron first emerged.
But scientists, including those in Sweden and China, are finding in lab tests that the variant appears to be less concerning than first thought.
U.S. scientists are among those who will release lab results soon, CNN reported.
So far, BA.2.86 has spread to the United States and 10 other countries. Denmark has reported the most sequences. In all, about three dozen sequences have been seen in a global repository over the past month, CNN reported.
“My friends, this is not the second coming of Omicron. If it were, it is safe to say we would know by now,” Dr. Bill Hanage, an epidemiologist who is co-director of Harvard University’s Center for Communicable Disease Dynamics, said in a social media post.
The ongoing lab experiments are using virus isolated from patients or models of the virus’ spike proteins grafted onto the body of a different virus, CNN reported.
In China, researchers determined that BA.2.86 looks different to the immune system than earlier COVID variants. It can escape some immunity, CNN reported.
Among the findings are that there was a twofold drop in the ability of vaccination and recent infection to neutralize BA.2.86, compared to viruses from XBB.1.5, Yunlong Cao from the Biomedical Innovation Center at Peking University, told CNN. But it was also 60% less infectious than XBB.1.5 variants.
“I would say it will slowly circulate in the population. It will not be able to compete with other fast prevailing variants,” Cao said, referring to variants like EG.5 and FL.1.5.1, which arecurrently spreading in the United States.
Meanwhile, in experiments at the Karolinska Institute in Sweden, researchers used blood from human donors collected in late 2022 and from late August to test the impact of antibodies against BA.2.86.
While the older blood samples couldn’t stop BA.2.86, those obtained later did better, CNN reported.
“Overall, it doesn’t appear to be nearly as extreme a situation as the original emergence of Omicron,” principal researcher Benjamin Murrell wrote in a social media post.
“It isn’t yet clear whether BA.2.86 [or its offspring] will outcompete the currently circulating variants, and I don’t think there is yet any data about its severity, but our antibodies do not appear to be completely powerless against it,” he said.
Both studies have limitations: Among them are that researchers were testing models of the virus, and not the actual virus, CNN reported.
Yet, the results were encouraging.
“The news is better than I was expecting,” Dr. Ashish Jha, former White House COVID-19 response coordinator said in a social media post. “And [it] makes me more encouraged that the new upcoming vaccine will have a real benefit against current dominant variant [EG.5], as well as BA.2.86.”
The U.S. Centers for Disease Control and Prevention has more on COVID variants.