A systematic review, published online in Annals of Internal Medicine, suggests that at least one third of SARS-CoV-2 infections remain asymptomatic. The review provides robust evidence for the prevalence of asymptomatic infections.

Investigators stated that the finding that about one in three people infected with COVID-19 do not develop any symptomsis an indication that testing needs to be changed. Lead author Daniel Oran stated that in order to limit the transmission of the virus from presymptomatic or asymptomatic individuals, the testing focus needs to be shifted to at-home screening.

The highest-quality evidence in this systematic review comes from large studies in England and Spain. The proportion of asymptomatic cases was 32.4% in England while it was 33% in Spain… (Medscape)