Does it matter which vaccine I get?
No. There's not much difference among the three authorized vaccines. Two, from Pfizer-BioNTech and Moderna, are based on mRNA technology, which directs the body to make the spike protein found on the surface of the SARS-CoV-2 virus.
The third, from Novavax, provides the same protein directly.
All three remind the immune system what the spike protein looks like, so when an infection arrives, it will be ready to quickly respond.
If you have had rough side effects after getting an mRNA vaccine, you might consider getting the Novavax shot this time, said John Moore, a professor of microbiology and immunology at Weill Cornell Medical College in New York.
As for mixing shots, that has been part of the dialogue since COVID-19 arrived, and now there's more clarity: Studies haven't shown a significant benefit to mixing and matching vaccines.