CHARLOTTE, N.C. — In the Carolinas, state health agencies report nearly a quarter-million people have gotten both doses of the coronavirus vaccine. Health officials have said one of the logistical challenges they face in fully vaccinating people is making sure people are getting the same brand for both shots.
But are there any situations when you can mix and match?
Can your two vaccine doses be from different brands?
Yes, you can have one dose from Pfizer and another dose from Moderna. However, the CDC states this should only happen in a rare, "exceptional" situation.
While the Centers for Disease Control and Prevention's initial guidance was previously cut-and-dried about not swapping brands, the agency quietly updated its recommendations in late January.
The CDC still states that "both doses of the series should be completed with the same product." However, it is now allowing clinicians more flexibility to accommodate rare situations.
"In exceptional situations... any available mRNA COVID-19 vaccine may be administered at a minimum interval of 28 days between doses," the CDC states in its latest guidance.
So, what's considered an "exceptional" case?
The CDC writes an exceptional case might be one where a person does not remember which vaccine they received and does not have documentation showing the brand. Another case might be if the first-dose brand was "no longer available."
Dr. Tony Moody, a professor of pediatrics with the Duke Human Vaccine Institute, said, while there is not any specific research on interchanging coronavirus vaccine brands, commonalities between the Pfizer and Moderna vaccines likely led the CDC to make this shift.
"They're very, very close, both in terms of the formulation, both being mRNA vaccines, but also in terms of the antigen that's in there--the thing that you're responding to," said Moody. "They're very similar. There's no reason at all to think that getting one wouldn't prime you for the other."
When asked whether it would be better for a person to wait an extensive period of time for their second dose of the same brand, or get the second shot of a different brand sooner, Moody said it really depends on the person's situation and how quickly they need the full immunity that two doses offer.
"There's no single right answer to it," said Moody. "If there is a reason to think that you have to have that second dose to have that complete series, then, getting it sooner rather than later is the right thing to do."