"No Evidence Of Coronavirus Being Airborne, Spreads Through Droplets Of Cough, Sneeze": ICMR

The Indian Council of Medical Research (ICMR) on April 5 said that there was no evidence of the virus being airborne adding that the number of Coronavirus cases in India is now doubling in just over four days.

"There is no evidence of coronavirus being airborne," Dr Raman Gangakhedkar, Head Scientist, (ICMR) was quoted as saying at the government's daily briefing.

Reportedly, the novel Coronavirus spreads primarily through droplets generated when an infected person coughs or sneezes, or through droplets of saliva or discharge from the nose.

The WHO in its latest update on the novel Coronavirus has also stated that according to current evidence, based on analysis of 75,465 COVID-19 cases in China, the virus is primarily transmitted between people through respiratory droplets and contact routes.

Terminology

Droplet transmission occurs when a person is in close contact (within 1 m) with someone who has respiratory symptoms (e.g., coughing or sneezing) and is therefore at risk of having his/her mouth, nose or eyes exposed to potentially infective respiratory droplets.

The virus can occur by direct contact with infected people and indirect contact with surfaces in the immediate environment or with objects used on the infected person (e.g., stethoscope or thermometer).

Airborne transmission occurs when the virus is present inside a 'droplet nuclei' which are generally considered to be particles <5μm in diameter, can remain in the air for long periods and be transmitted to others over a distance greater than one metre.

Recent Studies

Some scientific publications provide initial evidence on whether the COVID-19 virus can be detected in the air. According to WHO these initial findings need to be interpreted carefully.

In a recent publication in the New England Journal of Medicine, the persistence of the COVID-19 virus has been evaluated.

As part of the experiment, aerosols were generated using a three-jet Collison nebulizer and fed into a Goldberg drum under controlled laboratory conditions. This is a high-powered machine that does not reflect normal human cough conditions.

Another limitation of the study is that this was an experimentally induced aerosol-generating procedure and not an actual clinical setting.

There are reports from settings where symptomatic COVID-19 patients have been admitted and in which no COVID-19 RNA was detected in air samples.

According to WHO, there are other studies which have evaluated the presence of COVID-19 RNA in air samples, but which are not yet published in peer-reviewed journals.

"It is important to note that the detection of RNA in environmental samples based on PCR-based assays is not indicative of viable virus that could be transmissible," Who stated.

There continues to be a need for further studies to determine whether it is possible to detect COVID-19 virus in air samples from patient rooms where no procedures or support treatments that generate aerosols are ongoing.

Also Read: IIT Roorkee Develops Low-Cost Portable Ventilator 'Prana-Vayu' To Save Lives Amid COVID-19 Crisis