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What You Need to Know About Asymptomatic Spread of Covid-19
There’s been some confusion. Here’s what the science says.
Nearly six months have passed since Chinese officials first reported the emergence of a strange new pneumonia in Wuhan City. Despite months of concerted effort from the world’s scientific community, experts still aren’t certain just how the virus spreads — or who is capable of spreading it.
During a media briefing on June 8, an official at the World Health Organization set off a broad volley of expert rebukes when she said that it “appears to be rare” for an asymptomatic person to transmit the virus to others.
“We have a number of reports from countries who are doing very detailed contact tracing,” said the WHO official, Maria Van Kerkhove, PhD, who is that organization’s Covid-19 technical lead. “They’re following asymptomatic cases, they’re following contacts, and they’re not finding secondary transmission onward. It is very rare.”
In addition to Van Kerkhove’s comments, the WHO also published a report that stated: “Asymptomatically-infected individuals are much less likely to transmit the virus than those who develop symptoms.”
“The message should have been that symptom-free spread has been difficult to…
