A new study by the Council of Scientific and Industrial Research (CSIR) has shown that the chance of catching COVID-19 in the air depends directly on the number of infected persons in a room, as COVID droplets can travel far in closed spaces.
The CSIR study, yet to be peer-reviewed, was published in the medRxiv online archive. Researchers conducted the study "to understand air transmission characteristics of SARS-CoV-2 and risks for health care personnel and visitors to hospitals,” and highlighted that the demarcation of hospital areas into COVID and non-COVID zones is a successful strategy to prevent cross infections.
In neutral environment conditions, the study suggested, the virus does not seem to spread farther away from the patients, especially if they are asymptomatic. This gives objective evidence for the effectiveness of physical distancing in containing the virus transmission.
After international studies suggested that COVID is airborne, recent evidence suggests that the virus can travel up to 10 metres riding on aerosols. Aerosols are micro-droplets that come out of the mouth or nose of an infected person. CSIR’s scientists in India were the first to collect this evidence.
Air samples collected from several COVID and non-COVID, and ICU and non-ICU areas at hospitals in Hyderabad and Mohali, were analysed by the researchers, who performed closed room experiments with COVID-positive persons.
The study says, "Results indicate that the chance of picking up SARS-CoV-2 in the air is directly related to the number of positive cases in the room, their symptomatic status, and the duration of exposure and that the demarcation of hospital areas into COVID and non-COVID areas is a successful strategy to prevent cross infections."
Why Social Distancing Is Important?
Highlighting the importance of social distancing, the study said, "It is evident that the spread of the pandemic may be largely attributed to non-compliance of COVID-19 safety guidelines on the part of the people. A right amount of caution with courage backed up by sound scientific principles is the need of the hour."
Further, it added, "In neutral environmental conditions, the virus does not seem to spread farther away from the patients, especially if they are asymptomatic, giving an objective evidence for the effectiveness of physical distancing in curbing the spread of the epidemic."
Moreover, it has been discoursed that indoor transmission of the infection can be reduced if ventilation is improved. Merely opening windows and doors seems to cut the risk of transmission.
Better airflow can cut down the risk of most airborne infections and not just COVID-19, stated Dr Shekhar C Mande, Director General, CSIR, New Delhi.
Meanwhile, newer solutions like ultraviolet light disinfection of air offer some promise. New buildings also need to be designed in such a way that they incorporate the up-to-date ventilation codes as suggested by the CSIR, Roorkee.
Scientists earlier believed that the virus that causes the COVID-19 disease travelled and transmitted mostly through droplets but could not travel far.
This study comes at a time when India's daily COVID cases have dropped to around 40,000 daily cases of infection, in comparison to the peak during the second wave in May, when the daily cases reached 4 lakh infections a day.
However, as several states start unlocking in order to restart economic activity, many have warned against an impending third wave and urged to follow COVID appropriate behaviour.
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