Nearly 20 states have already detected cases of a new variant of the coronavirus, according to the Centers for Disease Control and Prevention (CDC). Omicron has made its way to the U.S. and around 40 other countries in just two weeks, which has virus experts concerned about its transmissibility. This latest iteration of COVID also has a number of mutations that were not seen with the still-dominant Delta variant, so experts are also worried that Omicron will evade the immune response created by existing vaccines in a way that previous variants have not. Vaccinated people remain the most protected against the virus, but even these individuals might need to take further precautions amid the new variant.
During a Dec. 8 interview with CNN’s Kate Bolduan, White House COVID adviser Anthony Fauci, MD, said that he believes the official definition of “fully vaccinated” in the U.S. will eventually change to include booster shots, especially as a result of the Omicron variant. According to the infectious disease expert, “it’s going to be a matter of when, not if” the additional shot will be required for vaccinated people to keep their fully vaccinated status.
To be clear, Fauci believes it’s unlikely that the definition will be amended in the immediate future. “Right now, I don’t see that changing tomorrow or next week,” he said. “Whether or not it officially gets changed in the definition, I think that’s going to be considered literally on a daily basis. That’s always on the table.”
The infectious disease expert’s remarks come as new data has just been released on how Pfizer’s vaccine protects against Omicron. In a Dec. 8 announcement, Pfizer and BioNTech revealed that lab experiments testing their vaccine’s effectiveness against the latest variant found that blood samples taken from patients who only had received the initial two doses showed a 25-fold reduction in antibodies. The companies said that this decrease “may not be sufficient to protect against infection” from Omicron.
But samples taken from patients one month after they received a booster shot of Pfizer’s vaccine indicated an antibody response that was similar in strength to the levels that were recorded against previous variants after the first two shots, per The New York Times.
“I don’t think anybody would argue that optimal protection is going to be with a third shot,” Fauci told Bolduan. “For me, as a public health person, I just say, ‘Get the third shot. Forget about what the definition is.’ I just want to see people be optimally protected … and that’s unequivocally and unquestionably getting a third shot boost.”
For its part, the CDC has yet to give any indication that it is considering updating its definition for full vaccination against COVID. In fact, CDC Director Rochelle Walensky, MD, said in early November that the agency was “not examining changing” it any time soon, per Axios, and she has continued to reiterate that over recent weeks.
“The definition of fully vaccinated has not changed,” Walensky said during a Nov. 30 White House COVID Response Team press briefing. “We are absolutely encouraging those who are eligible for a boost six months after those mRNA doses to get your boost. But we are not changing the definition of fully vaccinated right now.”
And while Fauci told Bolduan that the CDC’s definition of fully vaccinated is the basis of existing vaccine mandates, some officials are already taking the next step to require booster shots without the agency’s aid. Several major U.S. universities, including Notre Dame, Syracuse University, and Wesleyan University, have already announced that they are expanding their existing requirements to include booster doses, according to University Business.
“There’s no good reason to hesitate” requiring boosters, Michael Roth, the president of Wesleyan University, told NPR. Wesleyan was one of the first universities to issue a booster mandate. “Some people don’t like to be first,” he added. “But in this case, being first for public health doesn’t seem to be a particularly risky place to be.”