Evidence of Airborne Coronavirus Transmission

In News

New research found evidence of the risk of airborne transmission of coronavirus.

In-Detail

• New study in Hyderabad and Mohali has found evidence that the risk of airborne transmission of the coronavirus is if maintained sufficient physical distance and avoiding prolonged interaction with an infected person.
• Initially, the cause of COVID-19 was thought to be transmitted through contact and droplets during speech, coughs, or sneezes.
• Later several studies reported transmission happened by sharing enclosed spaces like a closed room or vehicle.
• This showed that there is a possibility of virus travelling through air to greater distances than two or three feet which was considered as the zone of risk.
• The study was a joint collaboration between Scientists from the Centre of Scientific and Industrial Research (CSIR), the Centre for Cellular and Molecular Biology (CCMB) in Hyderabad, and the Institute of Microbial Technology in Chandigarh.
• The study conducted in the two cities found that the risk of exposure in closed rooms through airborne transmission was higher and in normal circumstances the virus was not found more than four feet from the infected person.
• Researchers said that demarcating COVID and Non-COVID areas was a good strategy and masks were still very effective.

Findings of the Study

• Researchers collected 64 samples from six hospitals in different locations in two cities.
• Researchers also collected 17 samples from closed rooms which were occupied by the infected persons who were without masks and were asked to talk on the phone or with one another.
• From COVID areas of hospitals, four samples were taken and one from the closed room was to contain the virus.
• The strategy of separating COVID and Non-COVID care areas was effective as the virus could not be detected in the non-COVID areas.
• When the number of COVID patients was higher in the room, the positivity rate was found to be higher.
• The hospital experiments were that in three-fourths of the samples were positive and the person was 10 feet away from the nearest patient.
• This led to the conclusion that the long term presence of COVID positive patients in an enclosed space contributes to the significant increase in the aerosol burden in the air.
• In the neutral conditions, there was no particular airflow direction and the virus did not travel in the air.
• The virus could not pick up even at a distance of 4 feet when COVID positive patients spent a short time of 20 minutes in the room.
• This resulted in short term of exposure to COVID patients who may not put one at significant risk.
• The samples collected at a distance of 8 feet and 12 feet were also negative.

Recommendations

• The CSIR issued an advisory-
  • Public Transport
    • With adequate precautions, exposure to COVID-19 patients for a short duration does not increase the risk of contracting diseases.
    • The short duration travel in Metro or local trains and buses is safe.
    • For long-distance travel, the journey should be broken into two parts to minimize the risk.
  • Caution on Public Toilets
    • The potential to generate aerosols while flushing can stay longer in the air and it is known that the virus is excreted through stool.
    • Masks should always be kept while using public toilets.
    • The same toilet should be reused half an hour after the previous use and followed by adequate hand hygiene.
  • Home and Hospitals
    • Even if the social distance is maintained, spending more time in closed spaces is a risk.
    • Less risk of infection is possible in open and ventilated spaces.
    • If a person tests COVID-19 positive in a family, a home quarantine is advised and the person should be isolated in a separate room to prevent the infection from spreading.