Can I get one dose of one of the mRNA vaccines and the second dose from the other mRNA vaccine?
We are so glad that you want to get vaccinated! Please: get whichever one is available to you first. The efficacy and the safety data of all three vaccines (Pfizer, Moderna, and Janssen) are very comparable to each other (neither one was “better” than the others). Due to supply and/or logistical issues, one may be available to you before the other.
Many have been concerned because of a perceived lower efficacy of the Janssen vaccine. It is very important to know that the Janssen vaccine clinical trials ran after the Pfizer/Moderna trials did, and in countries with a high prevalence of the new COVID variants. Despite this, the Janssen vaccine efficacy was incredibly good and it still protected against hospitalization and death from COVID. We do not know how the Pfizer or Moderna vaccines would have performed in similar situations, so the vaccine trials are not directly comparable.
The one thing we DO know is that all three vaccines have been shown to be protective against severe COVID or death from COVID, and that the longer we go without vaccinations the more time the virus has to make new variants. So we strongly urge people to get whichever vaccine is available to them first!