Evidence on COVID-19 vaccine efficacy/effectiveness (VE) in preventing asymptomatic SARS-CoV-2 infections is needed to guide public health recommendations for vaccinated people. We report interim results of a living systematic review. We identified a total of 30 studies that investigated VE against symptomatic and/or asymptomatic infection. In fully vaccinated individuals, VE against symptomatic and asymptomatic infections was 80-90% in nearly all studies. Fully vaccinated persons are less likely to become infected and contribute to transmission.
Keywords: COVID-19; SARS-CoV-2; systematic review; vaccination; vaccine effectiveness.