mRNA vaccines like Pfizer and Moderna fare better against COVID-19 variants of concern

A comparison of four COVID-19 vaccinations shows that messenger RNA (mRNA) vaccines -- Pfizer-BioNTech and Moderna -- perform better against the World Health Organization's variants of concern (VOCs) than viral vector vaccines -- AstraZeneca and J&J/Janssen. Although they all effectively prevent severe disease by VOCs, the research suggests that people receiving a viral vector vaccine are more vulnerable to infection by new variants.