Colorado detected a single case of the Covid-19 omicron BA.2 sub-variant, which can spread faster and potentially “cause an increase in cases temporarily,” a state health official said Thursday.
The sub-variant, which has been detected in Europe and Asia, was identified in a person in the Denver area late last month, Rachel Herlihy, state epidemiologist, said during an online briefing.
Other states have detected a small number of cases.
“It could potentially result in an increased rate of transmission at least for a brief period of time,” Herlihy said. “There is no evidence that it causes any sort of increased level of severity.”
Moreover, it “doesn’t look that significantly different” from the original variant, called BA.1, Herlihy said.
The Centers for Disease Control and Prevention and other US agencies have prioritised characterisation of the BA.2 lineage, federal officials said.
Overseas, BA.2 became the dominant version of the virus in Denmark in the second week of the year, and Danish health authorities estimate it may be about 1.5 times more infectious than the BA.1 sub-variant, which accounts for about 98% of omicron cases globally.
Infections with the omicron variant have increased exponentially most likely due to a combination of increased transmissibility and the ability of the variant to evade immunity conferred by past infection or vaccination.