Airborne Spread Of Coronavirus: Should We Fear It? Here Is What Experts Think

After 239 scientists from 32 countries wrote an open letter to the World Health Organization(WHO), there is a growing fear of airborne coronavirus. But experts say that the coronavirus is airborne only in special circumstances.

(PTI Photo)

New Delhi: A few days ago, 239 scientists from 32 countries wrote an open letter to the World Health Organization(WHO) about evidence that indicates that the coronavirus is airborne. “Studies by the signatories and other scientists have demonstrated beyond any reasonable doubt that viruses are exhaled in microdroplets small enough to remain aloft in the air and pose a risk of exposure beyond 1 to 2m by an infected person,” said Professor Lidia Morawska, director of the International Air Quality and Health Laboratory, Queensland University of Technology(QUT). In the case of airborne infection, pathogens travel in the air and can be transmitted through aerosols or dust. These aerosols are generated by bodily functions such as sneezing or biological waste. Infection occurs when the microbes are inhaled by an individual. After the open letter was sent, the WHO's technical lead on the COVID-19 pandemic - Benedetta Allegranzi said that there was evidence emerging of airborne transmission of the Coronavirus, but that it was not definitive. "The possibility of airborne transmission in public settings - especially in very specific conditions, crowded, closed, poorly ventilated settings that have been described, cannot be ruled out," Allegranzi said, as quoted in a Reuters report. "However, the evidence needs to be gathered and interpreted, and we continue to support this," she added. But experts have highlighted the difference between a ‘truly airborne infection’ and airborne coronavirus. In a report by India Today, WHO's chief scientist Dr. Soumya Swaminathan has said that in the case of airborne infections, the pathogens travel primarily through the air. Whereas in the case of coronavirus, which is spread through respiratory droplets it can be considered in airborne in ‘special circumstances’. Normally, respiratory droplets come out of our mouth when we speak, sneeze or breathe and are of different sizes. The heavy ones fall to the ground but according to Swaminathan, there are ‘smaller droplets that are less than 5 microns in size’ i.e. aerosols which can remain in the air for longer duration and can be carried by the wind. “These particles could be inhaled by other people who are in the vicinity. This form of transmission of Covid-19 can be called as airborne transmission,” said Swaminathan in the report. In a report by news agency PTI, Rakesh Mishra, Director of the CSIR-CCMB also explained the same concept, “Those are good studies. Based on that, what is being communicated to WHO is that the virus can be at least temporarily airborne, which means it can travel in droplets of smaller size less than five microns which will mean that it will be hanging in the air for longer than bigger droplet which settles down in a few minutes.” He also emphasized that the precautions for covid 19 should continue and social distancing should be followed. He added that very little is known about the virus and it would be too early to say that enough had been known about it.