What healthcare professionals need to know

The BA.2.86 variant, also nicknamed “Pirola,” has recently attracted the attention of researchers and the media. Here’s an overview of what we know so far about this variant.

Origin and discovery of variant BA.2.86

The BA.2.86 variant was first identified in Denmark in July 2023, and was quickly classified as a “variant under surveillance” (VUM) by the World Health Organization in August of the same year. This rapid classification is due to the large number of mutations in the genes that encode the spike protein. France detected its first case on August 31 in Grand Est. Other countries, such as Switzerland, have identified the presence of this variant through wastewater monitoring even before clinical cases are detected. BA.2.86 is a descendant of Omicron’s BA.2 subvariant, which caused a major wave in the winter of 2022 before disappearing from the viral cycle.

Characteristics and public health implications

BA.2.86 has more than thirty mutations on the spike protein compared to the original Wuhan strain. This may indicate a possible immune escape, but remains to be confirmed at this stage. The first data also seem to indicate that the infectious potency of BA.2.86 is limited and that immune escape is minimal.

Yunlong Richard Kao, in a tweet On August 31, 2023, it publishes the first results based on the synthetic pseudovirus BA.2.86. According to his observations, this variant would offer less cellular infection compared to the XBB.1.5 and EG.5 variants. This decrease in infection could affect transmission. Three specific mutations, K356T, V483del, and E554K, could be responsible.

This means that current vaccines, especially booster doses that have been adapted to circulating variants, should remain effective against these variants.