In the online Science Says interview with Dr. Thomas J. Lynch, president and director of Fred Hutch, Liu said BA.2 may be outcompeting the original omicron variant in Denmark, India and parts of Asia, but it does not appear to have altered the declining trajectory of COVID-19 in the U.S.
She told Lynch, who holds the Raisbeck Endowed Chair, that both locally and in other parts of the nation, “the case counts have started to decline, which is positive news for everybody.”
“The good news is that the data seem to suggest there does not appear to be increased severity of illness associated with BA.2, and preliminary data from the U.K. suggest that the booster doses offer similar levels of protection against BA.1 and BA.2,” Liu said.
Antivirals, antibody drugs and omicron
Physician-scientist Dr. Elizabeth Duke, who has been overseeing trials of the antiviral drug molnupiravir at the Hutch's COVID-19 Clinical Research Center, discussed the impact of omicron on authorized antiviral drugs in a Jan. 28 article in Popular Science.
While omicron and its BA.2 "sister" subvariant are more likely to cause breakthrough infections among those vaccinated, antiviral pills or the intravenous drug remdesivir still seem to retain their effectiveness in preventing hospitalizations.
Extensive mutations on the spike proteins that dot the surface of the coronavirus are responsible for diminished effectiveness of vaccines that target the spike. They also have rendered some of the spike-targeting monoclonal antibody drugs ineffective. But the antiviral drugs molnupiravir, remdesivir and Paxlovid target processes at work within the virus, rather than the spikes.
“Based on the mechanism of the antivirals I would expect it to work against omicron and also future variants," Duke said. “It’s really nice to have the antivirals as a complementary part of our treatment approach, and this is something that is coming out at just the right time."
Omicron adds uncertainty to forecasts
NBC News noted on Jan. 28 that the sudden emergence of omicron is making it more difficult to forecast the direction the COVID-19 pandemic will take.
“I have just been so humbled and surprised by these variants of concern and the number of unanswered questions we have about them, where they came from, why they arise,” said Fred Hutch virologist and disease modeler Dr. Joshua Schiffer told NBC news reporter Evan Bush. "It’s difficult to project whether one of the viruses will permanently displace another or whether they’ll coexist in the population or whether a new variant will displace both of them.”
Also on Jan. 28, Bedford delivered in a Twitter thread a tutorial on the BA.2 subvariant. His view is that, while this new version will likely lengthen the time it takes for the current omicron wave to fade, "it won't drive the scale of epidemics we've expericenced with omicron in January."
In his new thread, Bedford charts of the family tree of COVID-19 variants. The original BA.1 omicron variant is labeled in his Nextstrain system as 21K, and its newer cousin BA.2 is called 21L.