Here are a list of studies related to the subject of asymptomatic transmission. The below studies find the instance to be close to zero.
The original study that postulated asymptomatic transmission on March 5th, 2020, involving a Chinese woman visiting Germany for business. She was in fact taking cold medication and symptomatic at the time. Christian Drosten, M.D., coauthor and a influential virologist in Germany, helped promote asymptomatic transmission as a reason for harsh public health restrictions.
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