COVID-19 Variants: BA.2.86 Variant Under Watch

The World Health Organization's evolution advisory group has labeled the BA.2.86 variant as monitored due to significant mutations. This decision follows recent detections in Israel, Denmark, and Michigan. Additionally, the EG.5 variant, initially monitored since July 19, was promoted to a variant of interest on August 9 by the WHO. The European Centre for Disease Prevention and Control (ECDC) has also designated EG.5 and other F456L mutation-bearing viruses as variants of interest due to rising transmission in Europe and globally.

WHO Calls For Increased Sequencing Efforts

The World Health Organization (WHO) is calling for increased sequencing efforts. In recent days, virologists from Israel and Denmark shared on social media a couple of sequences that seem to be second-generation versions of the Omicron BA.2 variant, provisionally referred to as BA.X. These sequences exhibit numerous mutations, particularly on the spike protein. The fact that these sequences have been found in two distinct regions, coupled with the global decrease in sequencing, suggests that the virus might be spreading more extensively. Additionally, the presence of these numerous mutations raises inquiries about various potential outcomes.

The WHO Indicated That The Earliest Recorded Specimen Dates Back To July 24

Maria Van Kerkhove, the WHO's COVID-19 expert, highlighted on Twitter the addition of a variant under monitoring (VUM), noting the need for increased vigilance due to the significant mutations. She stressed the importance of surveillance, sequencing, and reporting to track and detect new COVID-19 variants while emphasizing the ongoing threat of the virus and the likelihood of new variants emerging as it evolves.

Virologist Nick Rose tweeted that a sequence from Michigan collected on August 3 has been added to a sequencing database, marking the fourth confirmed identification of the BA.2.86 variant. Science teacher and variant tracker Ryan Hisner cautioned that predicting the impact of BA.2.86 is premature, but initial signs of widespread geographic spread suggest that it may not disappear rapidly.

Denmark's Statens Serum Institute (SSI) recently reported that neither of their two cases of BA.2.86 were among immunocompromised individuals and had no apparent epidemiological links. Currently, there is no indication that the variant causes severe illness. SSI also announced its plan to culture the virus for more comprehensive characterization.

The ECDC Intensifies Its Surveillance Of The F456L Mutation In The Virus

The ECDC reported a rise in COVID transmission in specific European countries, coinciding with increased detections of viruses associated with XBB.1.5 carrying the F456L spike protein mutation. While EG.5 is the prominent variant with this mutation, other lineages in the XBB.1.5 group also share it, like FE.1 from Brazil.

Viruses with this spike protein alteration are growing faster, observed in the US, UK, and Europe, possibly due to the mutation itself. FL.1.5.1, dominant in the Dominican Republic and elsewhere, also benefits from this mutation. Examples also include XBB.1.16.6 and XBB.1.5.59.

Hospitalizations and healthcare strain haven't shown an increase. The ECDC suggested that the transmission growth might be due to enhanced immune evasion and waning immunity, but it acknowledged other contributors, like large holiday gatherings. It emphasized no current signs of heightened hospitalizations or healthcare pressure.