Why UCSF’s Bob Wachter Says COVID Variant BA.5 Is ‘A Different Beast’

The new BA.5 strain of the COVID-causing virus is “a different beast” than the one we’ve already seen – more contagious and better able to evade immune responses – and “we need to change our thinking” about how we can defend against it, according to a Twitter full of data thread posted today by Dr. Bob Wachter, UCSF’s president of medicine.

BA.5, a sub-variant of the Omicron family that has an altered version of the virus’ infamous “spike” protein, will soon become the dominant strain of the virus in the US, meaning “its behavior ahead of our fate over the next few months, until it either burns itself out by infecting so many people or is replaced by a variant that’s even better at infecting people,” Wachter wrote.

“Neither is a joyous scenario,” he added.

The number of new COVID cases per day has stabilized nationwide and has fallen significantly since January. The same is true for the number of COVID hospitalizations in the UCSF health system, Watchter said. However, the true spread of COVID is harder to figure out these days because so many people are testing themselves with at-home kits.

And BA.5 could trigger a sustained plateau, or even a new wave of infections and possibly hospitalizations, because it infects more easily and is also better at evading immune responses — even in vaccinated people, Wachter wrote.

While he emphasized that vaccines and vaccine booster injections “remain immensely valuable in preventing a severe case” that could lead to hospitalization or death, the increased slipperiness of BA.5 means existing vaccines are likely to be less effective at preventing mild COVID-19. cases or stopping transfer in the first place. Also, he wrote, previous infection by another variant “no longer provides robust protection against reinfection” with BA.5.

What should a person do then?

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Wachter said it depends on how badly you want to avoid getting COVID. Personally, he said he doesn’t want to risk getting “Long COVID” and the debilitating symptoms that come with it: “So I still avoid dining indoors and will continue to wear an N95 in crowded indoor spaces until the number of cases goes way down.” is.” Others may make different choices.

As for governments, he said, if BA.5 triggers a wave of hospitalizations, “especially if we also have staff shortages,” a return to masking mandates “would be the right decision.” But Wachter acknowledged that there would likely be fierce resistance to new mask-wearing requirements, especially outside the blue states, regardless of the danger.

“Most people have ditched their masks,” he wrote.

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