PBS Newshour The latest variant, or sublineage, of SARS-CoV-2 to emerge on the scene, BA.2.86, has public health experts on alert as COVID-19 hospitalizations begin to rise and the new variant makes its way across the globe.
The Conversation asked Suresh V. Kuchipudi, a virologist and infectious disease expert at the University of Pittsburgh School of Public Health, to explain what researchers know about BA.2.86’s ability to dodge immune protection and whether it causes more severe infection than its predecessors.
What is BA.2.86 and how is it related to earlier variants?
BA.2.86, nicknamed Pirola, is a highly mutated new omicron sublineage of SARS-CoV-2 that was first detected in Denmark in July 2023. The World Health Organization announced that, as of Sept. 6, 2023, BA.2.86 has been detected in 11 countries.
A variant is an alternate version of a virus – in this case, the SARS-CoV-2 virus that causes COVID-19 – that has some mutations or changes in its genetic code, compared with the original. Mutations can alter the behavior of the viruses in various ways, such as how effectively they break into cells and how rapidly they can replicate.
The WHO names these variants using Greek alphabet letters, like alpha, delta and omicron. However, another naming system called the PANGO, or pangolin – short for phylogenetic assignment of named global outbreak lineages – tracks variants and their offshoots by way of a lineage system.
Think of it as a family tree for the virus, which is grouped into different lineages, like branches on a tree. The omicron variant is like a big family, and its known family members – BA.2, BA.2.86 and XBB.1.5 – are all branches – or lineages and sublineages – on the same tree.