COVID ‘variant soup’ is making winter surges hard to predict
Although the overall cases of COVID-19 seem to be falling, the mixes of variants, including the unprecedented diversity seen with immunity-dodging offshoots of the Omicron variant of SARS-CoV-2, it is very hard to predict the upcoming waves of infection. Because of such an intense proliferation by descendants of Omicron with the same mutations coming up over and over, scientists worry about the possibility of some ‘double waves’ in some places, as first one variant and then another overtaking a population subsequently.
Amidst such uncertainty, the available data are leading to some patterns. Scientists are. pinpointing a handful of immunity-evading mutations that power a variant’s spread globally. In Europe, North America, and Africa, the prevalence of Omicron offshoots in the BQ.1 family seem to be rising quickly. In Asian countries, including Singapore, Bangladesh, and India, a lineage called XBB dominates the fresh waves of infections. To simplify it, both strains seem to be circulating in several regions. It is not yet known the extent to which infection with one lineage elicits cross-immunity against the other. Scientists worry that the cold Northern Hemisphere winter weather could give SARS-CoV-2 circulation a boost, leading to unforeseen waves.