Presence of omicron ‘sub-variant’ confirmed in Washington state
The Washington State Department of Health has identified a new sub-variant of omicron, after confirming its presence in two new COVID-19 cases.
The sub-variant has been officially labeled BA.2, and according to the state DOH, it is “not considered clinically different” from omicron. More colloquially, it’s been described by some as “stealth omicron,” due to genetic traits researchers say make it more difficult to detect in testing than its sister variant.
Prior to being identified in Washington, BA.2 was detected in Denmark, the United Kingdom, and India, having quickly grown in prevalence in those countries since it first surfaced. In Denmark, it’s estimated that it already accounts for roughly 65% of the country’s new cases.
According to Imperial College virologist Dr. Tom Peacock, the sub-variant’s growth in other countries indicates that it “may be some degree more transmissible” than the original omicron iteration, although little more is known past that.
“Unfortunately this is really where the evidence mostly ends,” he said on Twitter. “We do not currently have a strong handle on antigenicity, severity or much evidence for how much more transmissibility BA.2 might have over BA.1.”
In Washington, the DOH says that because it “does not report sublineage breakdowns in the weekly variant report,” BA.2 cases will continued to be lumped in with totals for all omicron cases.