Seattle researcher: COVID variant could ‘push against’ recent improvements
COVID-19 case rates in the United States have now fallen back down to levels last seen in October 2020, amid concerns that variant strains of the virus could slow the nation’s recovery.
As Fred Hutchinson scientist Trevor Bedford points out, cases have been on a steady decline between November and February, broken up by a brief “inflation” in December, before rates stabilized again in mid-January.
Bedford believes that this likely means that the surge of cases that began in late 2020 could be coming to an end soon.
“Solely based on continued improvements to seasonality and continued increase in population immunity due to natural infection and vaccination I’d expect this trend to largely continue and the US fall/winter surge to be brought further under control,” he detailed on Twitter.
There’s also a caveat to that good news, largely driven by the “rapid take-off” of more the more infectious B.1.1.7 variant strain that was first detected in the United Kingdom.
Bedford believes that the variant could “push against” recent improvements in case counts, based on growth rates seen in countries like Denmark and Switzerland. Based on that data, the variant could reach 50% frequency in the U.S. “by perhaps late March.”
Even so, the more infectious strain will also face resistance from increased vaccination rates and warmer weather that typically drives people outdoors.
“It’s not clear to me at this point whether biological increase in transmissibility of B.1.1.7 will ‘win’ against further improvements to seasonality and immunity in ~6 weeks time at the end of March,” Bedford described. “Increased transmissibility of B.1.1.7 will certainly stretch out circulation of COVID-19 and make it harder to bring under control relative to the non-B.1.1.7 scenario.”
“But I’m not sure at this point how much of a spring B.1.1.7 wave to expect,” he added.
Ultimately, he believes that we’ll be able to draw more concrete conclusions as the variant’s presence escalates in Denmark and Switzerland, or states like Florida where it’s already more prominent than it is in the rest of the U.S.