MACON, Ga. — As Central Georgians are getting ready to receive their second dose of the COVID-19 vaccine, some of you have asked if your second dose has to be the same brand as your first.
We spoke to three infectious disease specialists and checked the CDC website to verify, so does it matter which brand you get at your second appointment?
According to our experts, it does.
Dr. Jennifer Hoffman with Coliseum Medical Centers says you've got to stick with the same brand.
"We know that two doses of Pfizer work. We know that two doses of Moderna work. We have not looked at what happens when you mix and match."
Both Dr. Jeff Stephens with Navicent Health and Dr. Don Nelson at Fairview Park Hospital agree.
"Even though the technology is similar, they're not exactly the same," says Stephens. "They are slightly different. All the data is for the second dose to boost up the first dose."
"Although they're both messenger RNA vaccinations, the actual antigen is a little bit different from one to the other," says Nelson.
It's not that there have been negative side effects when you get one brand and then the other, medical experts just aren't sure what would happen.
"We haven't studied what happens when you mix and match. It's possible it would work, it's also possible it might not," says Hoffman.
Just a few days ago, the CDC updated their guidelines to say in "exceptional situations" where the brand of the first dose is unavailable or if you can't determine what brand someone got the first time, you can use whatever is available at the time, but it's still highly recommended you stay with the same brand.
They also recommend certain steps to ensure you're getting the same product both times:
- Keep your vaccine card given to you at your first appointment telling you which brand you got and when to come back for your second dose.
- Enroll in VaxText SM, a free text message-based platform to receive COVID-19 vaccination second-dose reminders.
- Make an appointment for the second dose before you leave, to "increase the likelihood that patients will present at the same vaccination site for the second dose."
"Try to stick with the same company, even if it means delaying your shot by a week or two," says Nelson. "Don't delay it indefinitely because that could be problematic, but certainly try to get it and stay with the same brand."
So, we can verify that yes, your second dose of the vaccine needs to be the same brand as your first.
The CDC has also updated their guidance on when to get your second dose amid a nationwide vaccine shortage.
They say the second dose should be given as close as possible to the 21-day window for Pfizer and the 28-day window for Moderna.
If that's not possible, the second dose of Pfizer and Moderna COVID-19 vaccines may be scheduled up to 6 weeks, or 42 days, after the first dose.