Giving 2 Doses of Different COVID-19 Vaccines Could Boost Immune Response

May 5, 2021

(NPR) – Typically, if you get a COVID-19 vaccine that requires two doses, you should get two of the same vaccine. Two Pfizer shots, or two Moderna shots. Not one and then the other. But in the future, that could change, either by necessity or by design. This idea of using two types of vaccines isn’t a new concept. It’s known as heterologous vaccination, although there’s a more colloquial term.