The World Health Organisation on Tuesday agreed to review the transmission mode of the ongoing coronavirus (COVID-19) as new evidence indicates that airborne transmission of the virus may be possible indoors.
The UN health agency during a virtual press briefing in Geneva said it is making 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.
About 239 experts had on Monday written an open letter to the international health agency asking it to review its stands on the transmission mode of COVID-19 as more scientific research indicated that airborne transmission of the virus may be a threat in indoor spaces.
WHO technical lead on COVID-19, Maria van Kerkhove, while responding to a question about the open letter, said the WHO welcomes interaction with the scientific community.
Ms van Kerkhove said that the group first wrote to the UN agency on April 1 and there has been “active engagement” since then.
“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,” she said.
She said WHO experts have been studying the various potential modes of coronavirus transmission, including by airborne or aerosol droplets, “also other channels such as from mother-to-child, and from animals to humans”.
“The agency is producing a scientific brief that consolidates the growing knowledge around this subject, which will be issued in the coming days,” she added.
Mode of transmission
Since the first outbreak of the new coronavirus in Wuhan, China in December, there have been various research on the behavioural patterns of the disease.
While much is still unknown, the virus has spread globally, infecting close to 12 million and killing about 546,765 people.
More people are at the risk of getting infected from the virus as the transmission rate is still very high especially in countries where community transmission is ongoing.
There is also no known cure or vaccine for the virus.
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”, cannot be ruled out.
She said the agency recommends “appropriate and optimal ventilation” of indoor environments, as well as physical distancing.
The scientists recommended that people should avoid overcrowding, particularly on public transportation and in other confined spaces.
“Public buildings, businesses, schools, hospitals and care homes should also supply clean air, minimise recirculating air, and consider adding air filters and virus-killing ultraviolet lights,” they said in the letter.