Shanghai counted more than 20,000 new cases on April 7, but the asymptomatic rate has stood at around 97%, far higher than anywhere else in the world, where it has been closer to 50%.

Fu Chen, head of the municipal Center for Disease Control and Prevention, said in a written reply to Reuters’ questions that Shanghai’s rapid surveillance testing was contributing to the big asymptomatic numbers by catching infections earlier.

He also said high vaccination rates were also having an impact, as vaccinated people are less likely to show symptoms.

Source: Shanghai’s high asymptomatic COVID rate could be due to including mild cases | Reuters

By EdwardM