Omicron subvariant BA.2 replicates faster in brain cells than other strains, study finds
- It also causes ‘a substantially higher magnitude’ of programmed cell death in human brains, according to Hong Kong team
- They say more research is needed on the neurological impact of strains such as BA.2, which was dominant early this year
The study findings were published in a letter in peer-reviewed science journal Nature on November 20.
It is not the first study into neurological problems – such as disturbed brain function, inflammation and dementia – caused by Covid-19.
But the Hong Kong researchers aimed to find out if, and how, Omicron subvariants behaved differently in terms of impact on brain cells compared to earlier strains.
To do this, the scientists developed cells in the laboratory that mimicked human brain cells and challenged them with the Omicron variants BA.1 and BA.2, as well as the earlier Delta variant and the original, or wild-type, strain detected in Wuhan at the start of the pandemic.
They found that BA.2 replicated much faster than other strains in experiments on in vitro forebrain and midbrain cells. BA.2 was also found to induce a lower level of interferon – a protein released by the human body as a defence mechanism against viral infections – than other strains.