Covid-19: four fifths of cases are asymptomatic, China figures indicate

TLDR

New evidence from China shows that most coronavirus infections are asymptomatic, with about four in five cases showing no symptoms. Among 166 new cases reported on 1 April, 78 % (130) were asymptomatic, and the majority of symptomatic cases were overseas arrivals.

Abstract

New evidence has emerged from China indicating that the large majority of coronavirus infections do not result in symptoms. Chinese authorities began publishing daily figures on 1 April on the number of new coronavirus cases that are asymptomatic, with the first day’s figures suggesting that around four in five coronavirus infections caused no illness. Many experts believe that unnoticed, asymptomatic cases of coronavirus infection could be an important source of contagion. A total of 130 of 166 new infections (78%) identified in the 24 hours to the afternoon of Wednesday 1 April were asymptomatic, said China’s National Health Commission. And most of the 36 cases in which patients showed symptoms involved arrivals from overseas, down from 48 the previous day, the commission said. China is rigorously testing arrivals from overseas for fear of importing a …