World Health Organization reviewing study on concerns over airborne spread of Covid-19

They advise medical workers performing such procedures to wear heavy duty N95 respiratory masks and other protective equipment in an adequately ventilated room.

Professor Jose Vazquez-Boland, Chair of Infectious Diseases at the University of Edinburgh, said, "A problem here is the potential conflict between the technical notion of airborne transmission and the perception of the general public about this term". "COVID-19 has taken so much from us".

In a mildly alarming update, the World Health Organisation (WHO) on Tuesday acknowledged that there is "evidence emerging" which shows that the SARS-CoV-2 coronavirus might be spreading "airborne", leading to a whole new timorous dimension to the raging coronavirus disease (COVID-19) pandemic outbreak. But the researchers from 32 countries said that smaller respiratory particles can linger in the air and infect people.

In a media briefing on Tuesday, July 7, Maria Van Kerkhove, the WHO's head of emerging diseases and zoonosis unit, said that they have been discussing the possibility of airborne transmission, aerosol transmission, and droplet transmission as one of the modes of transmission of COVID-19.

"If airborne transmission is possible but rare, then eliminating it wouldn't have a huge impact", he said in emailed comments.

Benedetta Allegranzi, who leads the WHO's committee on infection prevention and control said the possibility of airborne transmission, especially in "crowded, closed, poorly ventilated settings", can not be ruled out.

Disclosing this at a virtual press briefing in Geneva, the agency said there are plans to update its advice on the transmission mode of COVID-19 after hundreds of experts urged the agency to reconsider the risk of aerosol transmission.

They can continue to take the same precautions, but masks should be worn for a longer time, he said.

But airborne transmission is possible in some circumstances, such as when performing intubation and aerosol-generating procedures, the World Health Organization says. "I can not imagine two more strong-minded, independent leaders to help guide us through this critical learning process", he said.

It meant, small droplets released when a person speaks or breathes would be in the air for some time.

If the evidence is confirmed, it could affect guidelines for social distancing indoors, such as in shops, restaurants, gyms and pubs. Businesses, schools and nursing homes may need to invest in new ventilation systems or ultraviolet lights that destroy the virus.

"A comprehensive package of interventions is required to be able to stop transmission", she said. "As everyone knows, if you ask a committee to design a horse, you get a camel".

Experts from more than 30 countries argue the health authorities are not paying enough attention to airborne COVID-19 transmission. It is therefore important to consider that studies that have failed to isolate live virus from air samples have done so as an artifact of the sampling technique used, not due to an absence of infectious virus. "Consequently, there is clearly a danger of people misinterpreting World Health Organization guidance regarding airborne transmission and underestimating the general risk of contracting COVID-19 through respiratory/ mucosal exposure (and the importance of wearing protective masks)", concluded Vazquez-Boland.

On Monday, a group of 239 global scientists said exhaled droplets under five micrometres in size that contain the virus can become suspended in the air for several hours and travel up to tens of meters.

She said: "Many of the signatories are engineers, which is a wonderful area of expertise, which adds to growing knowledge about the importance of ventilation which we feel also is very important". Julian Tang, honorary professor of respiratory sciences at the University of Leicester in the United Kingdom, said in an email. "Isn't that what the WHO stands for - the improvement of human health from all angles?"