A slew of studies suggests that mixing vaccines provokes potent immune responses, but scientists still want answers on real-world efficacy and rare side effects.

Given reports of myocarditis after vaccination with mRNA-based COVID-19 vaccines in young people, it's a good time to reexamine their risk/benefit ratio.

Given reports of myocarditis after vaccination with mRNA-based COVID-19 vaccines in young people, it's a good time to reexamine their risk/benefit ratio.

Given reports of myocarditis after vaccination with mRNA-based COVID-19 vaccines in young people, it's a good time to reexamine their risk/benefit ratio.

Given reports of myocarditis after vaccination with mRNA-based COVID-19 vaccines in young people, it's a good time to reexamine their risk/benefit ratio.