A less than third of all coronavirus patients might be asymptomatic, estimates a new study in Japan, triggering discussion on possible medical and government action on people carrying the virus without external symptoms in order to curb the spread of the deadly infection.
The study, which has been peer-reviewed and will be published in the International Journal of Infectious Diseases, based its research on Japanese people who were evacuated from China’s Wuhan province, where the disease broke out last year.
Using a statistical distribution, the study estimated that the number of asymptomatic patients stood at 30.8%. “Our estimation indicates that perhaps less than a half of Covid-19-infected individuals are asymptomatic. This ratio is slightly smaller than that of influenza, which was estimated at 56–80%.There is great need for further studies on the prevalence of asymptomatic COVID-19 infections to guide epidemic control efforts,” the authors wrote.
The authors acknowledged that the original sample for the study was small, and heterogeneity among patients was not considered.