coronavirus cases may have been spread by asymptomatic people. “Data-reactid =” 41 “> An expert from the World Health Organization warned that 40% of coronavirus cases may have been spread by asymptomatic people.
Maria van Kerkhove, epidemiologist and WHO technical manager for the pandemic, said in a briefing Tuesday that people with coronavirus are more infectious when they first experience symptoms.
“The majority of the transmission we know is that people who have symptoms spread the virus to other people through infectious droplets, but there is a subset of people who do not develop symptoms, and for really understand how many people don’t have symptoms, we don’t have that answer yet, “said Dr. Kerkhove.
“Some estimates suggest that between 6% of the population and 41% of the population may be infected but have no symptoms, with a point estimate of around 16%.
“We know that some people who are asymptomatic or have no symptoms can transmit the virus.
“And so what we need to understand better is how many people in the population do not have symptoms and separately how many of these people continue to transmit to others. “
Dr. Kerkhove said that some modeling groups are trying to estimate “what proportion of asymptomatic people are likely to transmit.”
WHO says virus is “getting worse” around the world“Data-reactid =” 68 “> Find out more: WHO says virus is “getting worse” around the world
She continued: “And these are estimates and there are a wide range of different models, depending on how the models are made, where they are made, from which country.
“But some estimates of around 40% of transmission may be due to asymptomatic symptoms. But these come from models. “
transmission of the coronavirus by people without symptoms was “very rare”. “Data-reactid =” 71 “> Elsewhere in the press conference, Dr. Kerkhove sought to clarify the comments she made on Monday, in which she suggested that the transmission of coronavirus by people without symptoms was “very rare”.
She said in the previous WHO briefing: “We have a number of country reports that are doing very detailed contact tracing.
“They follow asymptomatic cases, they follow contacts and they do not find secondary transmission. It’s very rare. “
But on Tuesday, she said she was referring to “two or three studies”.
She added, “I was answering a question at the press conference. I was not stating a WHO policy or anything like that. I was just trying to articulate what we know.
“And in that, I used the expression” very rare “, and I think it is a misunderstanding to say that asymptomatic transmission in the world is very rare. What I was referring to was a subset of studies. “