20% of staff in a U.S. supermarket are infected by coronavirus, most of them are asymptomatic

The journal “Occupational and Environmental Medicine” published a new survey on October 29, and for the first time emphasized the severity of the asymptomatic infection of the new coronavirus. 

The survey showed that 20% of 104 employees who were tested at a supermarket in Boston, USA in May tested positive, which is significantly higher than the number of confirmed diagnoses in surrounding communities.

The researchers pointed out that the staff in contact with customers are 5 times more likely to be diagnosed than other staff, but 75% of the confirmed staff have no symptoms. The report pointed out that due to ignorance of their own diagnosis, such persons have become a major source of transmission of the new coronavirus.