INDIANAPOLIS — As millions of Americans are trying to get two doses of the COVID-19 vaccine recommended by the CDC, some are wondering if those two doses must be the same brand of vaccine and if getting two different kinds of vaccine could actually be more helpful.
The question
Loren in Monticello, Ind., wrote VERIFY to say, “I know of a person who refused the second COVID-19 shot because what was available was the brand not received at the first shot. Is mixing Pfizer and Moderna shots OK or a problem?”
And Juanita emailed to say she’d like her second COVID-19 vaccine dose to be a different brand than the first “to get better protection for Covid19, especially the new variants. Is it safe and can it be done?”
Questions like these have been popular in the 13News VERIFY inbox since the New York Times published an article last month reporting health officials in Great Britain changed their vaccine guidelines to allow for a “mix-and-match” vaccine regimen.
So is mixing and matching different brands of the COVID-19 safe and perhaps even a good idea?
Our sources
Public Health England, the US Centers for Disease Control and the journal Nature.
What we found
Great Britain’s executive health agency known as Public Health England is not really advocating that its citizens get different vaccines. The agency’s latest guidance says “every effort should be made” to complete dosing with the same shot given during the first vaccination. But when “the same vaccine is not available, or if the first product received is unknown, it is reasonable to offer one dose of the locally available product” for the second vaccination.
Here in the US, the CDC takes a much stronger position against mixing and matching COVID-19 vaccines.
The CDC website says taking any of the approved vaccines is OK, but “COVID-19 vaccines are not interchangeable with each other or with other COVID-19 vaccine products. The safety and efficacy of a mixed-product series have not been evaluated. Both doses of the series should be completed with the same product.”
And the agency says different brands of the vaccine should be administered to the same person only in “exceptional situations."
The journal Nature reports British researchers launched a new study last week to determine the impact of giving individuals a shot of both the Pfizer and AstraZeneca vaccines – and whether that could even boost someone’s immune response compared to getting just one brand of vaccine. But getting the results of that Oxford University study will take time.
So is it safe to mix and match different types of vaccines? The short answer is: we don't know. That has not been tested, so we don’t have an answer yet.
But VERIFY can confirm the CDC and the national health department in England highly recommend sticking with one vaccine for both doses whenever possible.
Have a question you’d like us to VERIFY? Send us a email at VERIFY@wthr.com.