New Covid-19 Variant BA.2.86 Under WHO's Monitoring List

The U.S. Centers for Disease Control and Prevention on Thursday announced that it is tracking a recently discovered COVID-19 strain, BA.2.86 after experts discovered a case of the highly-mutated strain in Michigan.

"CDC is tracking a new lineage of the virus that causes Covid-19. This lineage is named BA.2.86 and has been detected in the United States, Denmark, and Israel.

"Today we are more prepared than ever to detect and respond to changes in the COVID-19 virus. Scientists are working now to understand more about the newly identified lineage in these 4 cases and we will share more information as it becomes available," CDC spokesperson Kathleen Conley was quoted as saying.

It comes after the World Health Organization announced it had classified BA.2.86 as a "variant under monitoring" due to its large number of mutations.

All viruses, including SARS-CoV-2, the virus that causes Covid-19, change over time, according to WHO. Most changes have little to no impact on the virus's properties. However, some changes may affect the virus's properties, such as how easily it spreads, the associated disease severity, or the performance of vaccines, and therapeutic medicines.

In a statement posted on X, WHO said more data are needed to understand this Covid-19 variant BA.2.86 and the extent of its spread, but the number of mutations warrants attention.

"WHO is tracking 3 variants of interest and 7 variants under monitoring at the moment. WHO continues to call for better surveillance, sequencing, and reporting of #Covid19 as this virus continues to circulate and evolve.".

Dr. S. Wesley Long, Medical Director of Diagnostic Microbiology at Houston Methodist, explained that the new lineage, which has 36 mutations from the currently-dominant XXB.1.5 Covid variant "harkens back to an earlier branch" of the virus.

He said it remains to be seen whether BB.2.86 will be able to out-compete other strains of the virus or have any advantage in escaping immune responses from prior infection or vaccination.