As new variants emerge, fully vaccinated people testing positive for COVID-19 won't be uncommon, Vin Gupta, MD, said Dec. 16 on the Today show.
Dr. Gupta, physician and affiliate assistant professor of health metrics sciences at Seattle-based University of Washington, said forecasts are predicting rising COVID-19 cases among both the vaccinated and the unvaccinated "well into March," noting that "this is going to be a very difficult three to four months ahead."
"We have to get comfortable with fully vaccinated folks testing positive," Dr. Gupta said. "The purpose of the vaccines is not to prevent a positive test for a respiratory virus like omicron, but to keep you out of the hospital — and that's exactly what they're doing."
Dr. Gupta said vaccines for respiratory viruses aren't necessarily expected to prevent positive tests or mild symptoms, but instead prevent severe disease.
Preliminary findings published Dec. 15 in preprint server MedRxiv suggest that two doses of Moderna's mRNA vaccine are less effective against the omicron coronavirus variant. However, a booster dose strengthened the antibody response against omicron at levels comparable to the shot's effectiveness against the delta strain. The study has yet to be peer reviewed.
Preliminary real-world data from South Africa also suggests that the omicron variant is more resistant to Pfizer's vaccine but causes less severe infections.
Dr. Gupta said he anticipates annual COVID-19 shots to be part of the new normal as well.