It seems that there’s a new COVID variant on the loose in the US. Check out more details about it and also take a look at the risks that it brings for health.
New COVID variant in the US
The BA.2.86 variant, also known as Pirola, is becoming widespread in the United States. According to the U.S. Centers for Disease Control and Prevention (CDC), its prevalence increased from 1 to approximately 9 percent between Oct. 28 and Nov. 25.
On Nov. 21, the World Health Organization identified Pirola as a variant of interest, but also determined that the public health risk posed by BA.2.86 was low at the global level. In a Nov. 27 update, the CDC concurred with the WHO’s evaluation, stating that “based on available limited evidence,” the public health risk posed by this variant is low compared to other circulating variants.
Pirola is a variant of the earlier Omicron strain, BA.2. Another variant, XBB.1.5, which also derived from BA.2, became the dominant strain in early 2023. However, the current dominant variant is H.V.1, which is derived from EG.5, an unofficially named variant known as Eris. Eris was previously dominant in the United States.
“At this time, BA.2.86 does not appear to be driving increases in infections or hospitalizations in the United States,” the CDC wrote.
Studies conducted outside of the United States have indicated that the Pirola variant is not expected to be more severe than the current variants. According to researcher Yunlong Cao, who has a doctorate in physical biochemistry from Harvard, Pirola has lower cell infectivity compared to XBB.1.5 and Eris.
A preprint study from Japan suggests that while Pirola may be more transmissible than Eris, which was a previous dominant variant, it is less likely to cause disease.
Sharing some new experimental data on BA.2.86:
1) BA.2.86 is antigenically distinct compared to XBB.1.5.
2) BA.2.86 can significantly escape XBB-infection/vaccination induced antibodies.
3) However, the infectivity of BA.2.86 may be much lower than XBB.1.5 and EG.5. (1/n) pic.twitter.com/sJZ8ySKxMG
— Yunlong Richard Cao (@yunlong_cao) August 31, 2023
Compared to Eris, Pirola has a significantly lower growth efficiency, meaning that it is less capable of replicating itself in the host, the authors wrote.
“This is not the second coming of omicron.
If it were, it is safe to say we would know by now,” Bill Hanage, associate director and professor of epidemiology at Harvard wrote on X on Sep. 1 ,when the variant’s prevalence was significantly lower.