Thompson and colleagues published encouraging results of the efficacy of mRNA vaccines in preventing COVID infection and in attenuating breakthrough infections in a cohort of healthcare workers from six states in the United States.

Adjusted vaccine effectiveness after complete vaccination was 91%, and 81% after partial vaccination.

Those with breakthrough infections after partial or complete vaccination had mean viral loads which were 40% lower than those in unvaccinated individuals, as well as a lower incidence of febrile symptoms and shorter disease duration:

For the full paper, head to the NEJM website.