The SARS-CoV-2, which was earlier thought to spread through touching infected surfaces, has been found to be spreading airborne and more evidence is coming up in this regard, with epidemiologists also finding that countries that used masks were affected less severely by the pandemic.
A collaborative study by a group of scientists from CSIR-Centre for Cellular and Molecular Biology, Hyderabad, and CSIR-Institute of Microbial Technology, Chandigarh, with hospitals in Hyderabad and Mohali, has confirmed the airborne transmission of SARS-CoV-2 in both ICU and non-ICU wings suggesting that patients shed the virus in air, irrespective of the severity of infection.
Scientists analysed the coronavirus’ genome content from air samples collected from different areas occupied by COVID patients including hospitals, closed rooms in which only COVID patients spent a short period of time, and houses of home-quarantined patients.
It was found that the virus could be frequently detected in air around COVID patients and the positivity rate increased with the number of patients present on the premises. The study also found viable coronavirus in air that could infect living cells, and these viruses could spread over a long range of distance, hence scientists still suggest wearing face masks to avoid the spread of coronavirus.
“Our results show that coronavirus can stay in the air for some time in the absence of ventilation in closed spaces. We find that the positivity rate of finding the virus in air was 75% when two or more COVID patients were present in a room, in contrast to 15.8% when one or no COVID patient occupied the room in these studies,” explained scientist Shivranjani Moharir.
She further said that their observations are concurrent with previous studies that suggest that the concentration of SARS-CoV-2 RNA is higher in indoor air as compared to outdoor air, and indoors, it is higher in hospital and healthcare settings that host a larger number of COVID patients, as compared to those in community indoor settings.
“Air surveillance is a useful means to predict infection potential of a space like classrooms and meeting halls. This can help refine strategies to control the spread of infections,” said lead scientist Rakesh Mishra, former director and now distinguished emeritus professor at CCMB, and also director of Tata Institute for Genetics and Society.
Air surveillance technique is not just limited to coronavirus but can also be optimised to monitor other air-borne infections, he added. The study has been published in the ‘Journal of Aerosol Science’, said an official release.
