Update on SARS CoV-2 Variant BA.2.86

September 8, 2023, 11:30 AM EDT

CDC is posting updates on respiratory viruses every week; for the latest information, please visit CDC Respiratory Virus Updates.

CDC is tracking a SARS-CoV-2 variant called BA.2.86 and working to better understand its potential impact on public health. This update follows CDC’s previous BA.2.86 updates on August 23, 2023 and on August 30,2023.

It is anticipated that the 2023-2024 COVID-19 vaccine will be available in mid-September. Learn more about ways to keep you and your loved ones safe as we head into the fall respiratory virus season.

What’s New?

  • The current increases in COVID-19 cases and hospitalizations in the United States are not being driven by BA.2.86 and instead are being caused by other predominantly circulating viruses.
  • Early research data from multiple labs are reassuring and show that existing antibodies work against the new BA.2.86 variant. These data are also encouraging because of what it may mean for the effectiveness of the 2023-2024 COVID-19 vaccine, which is currently under review. That’s because the vaccine is tailored to the currently circulating variants.
  • Since CDC’s initial risk assessment, BA.2.86 has been identified in additional countries from both human and wastewater specimens. The variant has been identified in nine U.S. states as of September 8, 2023, at 11:30 AM EDT— in people across Colorado, Delaware, Michigan, Ohio, Pennsylvania, Virginia, and Washington, as well as one additional human case that is being investigated. The variant has also been identified in wastewater samples in two states, New York and Ohio.
  • The U.S. SARS-CoV-2 Interagency Group (SIG) classified BA.2.86 as a Variant being Monitored (VBM) on September 1, 2023.

Recent Scientific Findings on the Immunology of BA.2.86

Because of the sequence divergence of BA.2.86, there was initial concern of a significant reduction in antibody activity. Preliminary data from laboratory-studies from multiple investigators suggest similar antibody activity against BA.2.86 as compared to other currently circulating viruses.

CDC and other experts are reassured by these research findings that support the effectiveness of this type of immunity against this variant. Additionally, based on CDC’s experience with past SARS-CoV-2 variants, people will likely have protection against severe disease mediated by both cellular and antibody immunity.  Real-world data are needed to fully understand the impact given the complexities of the immune response to this variant. Additional studies on this are ongoing, and we expect to learn more in upcoming weeks.

The remainder of CDC’s risk assessment remains unchanged from last week’s (August 30th) update.