Omicron is highly contagious and now experts say it does not provide much protective immunity, meaning you can be infected more than once.
The dean of Brown University School of Public Health, and a doctor with the World Health Organization tweeted warnings Friday, urging vaccinations and boosters.
And Bay Area experts agree, saying omicron can strike more than once as there are new cases indicating natural immunity after infection doesn't last.
“We're seeing second cases of omicron more often in people who didn't get vaccinated than in people who have been vaccinated, but second cases of omicron in both cases,” said Dr. John Swartzberg of UC Berkeley.
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He added that there is still a lot to learn about the new variant.
“We hardly saw any breakthrough infections with any of the variants until omicron,” said Swartzberg. “So clearly our immune system doesn't do as well against omicron as it has done against other variants.”
With omicron circulating widely in the Bay Area, doctors say vaccinations, boosters and masks are still your best protection against serious illness and hospitalization.