The World Health Organisation’s new coronavirus guidelines acknowledge some reports of airborne transmission, but stop short of confirming that the virus spreads through the air.
WHO said on Thursday, July 9, 2020 that some outbreaks are related to indoor crowded spaces, which suggested the possibility of aerosol transmission such as during choir practice, in restaurants or in fitness classes.
But the organisation said more research was “urgently needed to investigate such instances and assess their significance for transmission of Covid-19”.
The report follows an open letter from aerobiologists scientists who specialise in the spread of disease in the air that urged WHO to update its guidance on how the disease spreads to include aerosol transmission.
Based on its review of the evidence, WHO said the coronavirus that causes Covid-19 spreads through contact with contaminated surfaces or close contact with infected people who spread the virus through saliva, respiratory secretions or droplets released when a person coughs, sneezes, speaks or sings.
WHO’s new guidelines suggest people should avoid crowds and ensure good ventilation in building, in addition to social distancing, and encourage masks when physical distancing is not possible.
Dr Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases, said there was not a lot of solid evidence yet on airborne transmission, but added:
“I think it’s a reasonable assumption that it does occur.”
According to Dr Fauci, the evidence so far was “the fundamental basis for why we are now so intent on getting people – particularly people without symptoms – to wear masks”.