WHO Expert Clarifies Remark on COVID Spread By Asymptomatic Cases

WHO accepts that modelling studies estimate up to 40% of infections are transmitted by asymptomatic cases.

Updated
Coronavirus
2 min read
WHO accepts that modelling studies estimate up to 40% of infections are transmitted by asymptomatic cases.
i

World Health Organisation (WHO) expert Dr Maria Van Kerkhove acknowledged that modelling studies suggest that up to 40% of all coronavirus infections could be transmitted by asymptomatic people. This comes after her comments in a media briefing on Monday, where she had said that the extent of the spread of COVID-19 by someone who is not showing any symptoms seems to be ‘very rare’.

The WHO’s COVID-19 technical lead, still, however, maintained that real-world data shows it could be a rare event, not referencing to the modelling studies. Her initial remark was based on two or three studies which followed contacts of asymptomatic patients, and unpublished data shared by countries or experts, reports The Guardian.

“I used the phrase ‘very rare’ and I think that it’s a misunderstanding to state the asymptomatic transmission globally is very rare. What I was referring to was a subset of studies. I was also referring to some data that isn’t published.”
Dr Maria Van Kerkhove

WHO’s Earlier Statement

Dr Kerkhove had stated that the WHO has several reports from the countries doing very detailed contact-based tracing. The countries have been following cases with no or mild symptoms.

"It's odd how much of it isn't published in the literature," she said.

“We are constantly looking at this data and we’re trying to get more information from countries to truly answer this question. It still appears to be rare that an asymptomatic individual transmits onward.”

Van Kerkhove went on to explain how the novel coronavirus, a respiratory pathogen, passes on via droplets while coughing or sneezing.

“If we followed all of the symptomatic cases, isolated those cases, followed the contacts and quarantined those cases, we would drastically reduce -- I would love to be able to give a proportion of how much transmission we would stop -- but it would be a drastic reduction in transmission.”

She said many people who were thought to be asymptomatic to COVID-19 turned out to have cases of mild disease. There may be someone who doesn't have a fever yet, a notable cough or shortness of breath. Having said that, there are possibilities of having cases with no symptoms at all.

Pre-symptomatic points to the initial stages of an illness before symptoms have developed. Whereas asymptomatic means having no symptoms throughout the infection -- a distinction that Van Kerkhove hinted at throughout Monday's media briefing.

In India, nearly 66% of cases were thought to be asymptomatic. In an earlier interview with FIT, Dr Sumit Ray explained the difference between asymptomatic and presymptomatic patients and if that works to India's advantage.

(Make sure you don't miss fresh news updates from us. Click here to stay updated)

Published: 
Stay Up On Your Health

Subscribe To Our Daily Newsletter Now.

Join over 120,000 subscribers!