"(...) 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 fresh outbreak of covid-19. Tom Jefferson, an epidemiologist and honorary
research fellow at the Centre for Evidence-Based Medicine at the University of Oxford, said the findings were
“very, very important.” He told The BMJ, “The sample is small, and more data will become available. Also, it’s
not clear exactly how these cases were identified. (...)" |