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U-turn: WHO clarifies remarks after it said coronavirus transmission by asymptomatic people is 'very rare'

WHO expert Maria Van Kerkhove's remarks earlier had led to confusion among health officials who have recommended that people must wear masks to prevent the spread of the coronavirus.

June 12, 2020 / 08:22 AM IST

A top World Health Organization (WHO) expert has tried to clarify "misunderstandings" about comments she made that were widely understood to suggest that people without COVID-19 symptoms rarely transmit the novel coronavirus.

Maria Van Kerkhove, the UN health agency's technical lead on the pandemic, insisted on June 9 that she was referring only to a few studies, not a complete picture, in the comments she made a day earlier.

Van Kerkhove's remarks on June 8 had led to confusion and questions among other experts and health officials who have recommended, and in some places required, that people wear masks to try to prevent the coronavirus from spreading further.

The “clarification” she provided during a WHO social-media chat showed many questions remain about whether infected people who do not show symptoms of illness such as fever, dry cough or difficulty breathing can transmit the virus to others.

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Van Kerkhove said: “What I was referring to yesterday were very few studies, some two or three studies that have been published, that actually try to follow asymptomatic cases.”

“That's a very small subset of studies,” she continued. “I used the phrase 'very rare,' and I think that that is (a) misunderstanding to state that asymptomatic transmission globally is very rare. What I was referring to was a subset of studies.”

Studies show people with the novel coronavirus, which causes COVID-19, are most infectious when they first show symptoms, Kerkhove said.

She added that a sub-set of people do not develop symptoms, but can still infect others, and as many as 40 percent of transmissions may be by asymptomatic cases.

(With inputs from the Associated Press)

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first published: Jun 10, 2020 08:37 am