Health officials say it’s time for most Americans to get another booster dose—this time, with a new Omicron-specific shot made by either Pfizer-BioNTech (for people 12 and older) or Moderna (for adults 18 and older). But should you stick with the vaccine brand you’ve been using, or can you mix and match? Here’s what to know.
It is possible to mix and match booster doses.
Many COVID-19 vaccines were made available in America since 2020’s first shots. Currently, two primary-series COVID-19 vaccines (made by Pfizer-BioNTech and Moderna) are approved by the U.S. Food and Drug Administration (FDA), and two (made by Johnson&Johnson-Janssen and Novavax) are authorized for emergency use. Shots from Pfizer-BioNTech and Moderna are approved as booster doses, and J&J’s booster is authorized for those who received that brand for their one-dose primary shot, or for those who cannot safely receive the other boosters because of the risk of side effects.
The U.S. Centers for Disease Control and Prevention (CDC) recommends that people not mix the two primary series doses of the mRNA vaccine—so if you’ve been vaccinated with Pfizer-BioNTech for your first dose, for example, your second dose should also be from Pfizer-BioNTech; the same goes for Moderna. But the abundance of options means you may have already received a booster dose from a different manufacturer, and that’s just fine. Study after study showed that people who were given mRNA booster doses from the original vaccine manufactured by another manufacturer had similar levels of virus-fighting antibodies against SARS-2 to those who received the booster and primary shots.
The original boosters and vaccines were similarly affected. But human studies of the new Omicron boosters have not been completed yet—they will be launched in September—so there are no data yet on what happens when people who have been vaccinated with one company’s shots then get an Omicron booster made by a different company. It’s also not clear what happens, for instance, if someone who was vaccinated with Moderna’s shot, then boosted with Pfizer-BioNTech’s, now gets a Pfizer-BioNTech or Moderna Omicron booster.
But based on previous studies of mixing and matching, health officials are relatively confident that the booster doses are interchangeable, and the CDC says people over 18 “may get a different product for a booster than they got for their primary series, as long as it’s Pfizer-BioNTech or Moderna.”
One thing to keep in mind, however, is that all along, Moderna’s vaccine doses have been slightly higher than those from Pfizer-BioNTech. The same is true of Moderna’s new Omicron booster. A higher dose means that people getting Moderna’s Omicron booster may experience slightly higher rates of side effects, such as swelling, arm soreness, fever, and fatigue compared to people who get Pfizer-BioNTech’s. If the results of the first booster shots are any indication, it could be an advantage. Studies that were done earlier on people who had received the Moderna booster showed they produced higher levels of antiviral antibodies than people who had received the Pfizer BioNTech booster.
Is it possible to mix booster doses of vitamins for children?
This depends on the age of your child and what vaccines they have received. Children ages 12 to 17 who were vaccinated with either Moderna’s or Pfizer-BioNTech’s shots as their primary series can get boosted with Pfizer-BioNTech’s new Omicron booster. Neither Omicron booster is authorized yet for children under 12—so those children will still receive a booster of the original vaccine (if they’re eligible to get boosted).
If your child was vaccinated with Moderna as a primary series, Moderna booster doses of any kind—original or Omicron-specific—have not been authorized for children six months to 11 years old yet. This age group is advised not to receive booster doses of Moderna vaccine. Pfizer BioNTech vaccines can be used to boost the original dose of vaccinations.
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