COVID-19 Social Distancing: Study suggests 6 feet is not enough, virus can travel up to 20 feet

It is a fact that SARS-CoV-2 virus, the causative agent of COVID-19, can transmit through infectious droplets which spreads when an infected person coughs, sneezes or even breathes. To prevent this, doctors and scientists all over the world recommended that we maintain a social distance of at least six feet from each other. But in recent research by the scientists of the University of California and Stanford University, US, it was found that six feet distance may not be enough as the virus can travel as far as 20 feet. The research has not been published yet and is under peer review. [caption id=“attachment_8309391” align=“alignleft” width=“380”]  Representational image. AP[/caption]

Six feet apart: The previous social distancing norms

Authorities such as the Centers for Disease Control in the US and the Ministry of Health and Family Welfare in India had laid down some guidelines regarding social distancing amongst people after COVID-19 was declared a pandemic. According to these bodies, a person needs to maintain a minimum distance of two metres, i.e, six feet whenever they step out in public. This was done to prevent people from the possible spread of infection as when an infected person coughs or sneezes they release about 40,000 virus droplets in the air.

The research: Spread of virus in different environmental conditions

In recent research, scientists created a mathematical model which tested the spreading ability of SARS-CoV-2 containing droplets in different environmental conditions such as a change in temperature, humidity and wind velocity. In their study, the researchers tested the projectile motion and the evaporation of the viral droplets.

The results: Six feet social distance might not be adequate

In their study, the researchers found that as the weather changes, the spreading ability of the virus also changes. They found that in dry and hot weather, the droplets convert into aerosols which can transmit the infection to a longer distance. In such weather, the infectious aerosols of size as small as particulate matter 2.5 (which is smaller than 2.5 micrometres) can infiltrate deep into the lungs. On testing the virus’ ability in cool and humid weather, they found that the aerosol production was significantly reduced but the infection kept on spreading in the form of droplets. In such weather, about six metres (approximately 20 feet) of physical distance would be required to prevent the transmission. They further found that somehow ventilators are helping the transfer of both infectious droplets and aerosol particles to a longer distance. The improper use of ventilators in public spaces can work in favour of the virus and make transmission easier, especially in a humid and hot environment.

Conclusion

The scientists concluded that the current guidelines for social distancing may not be able to restrict the transmission of SARS-CoV-2 virus (especially in the aerosol form) under different weather conditions. They stated that proper covering of face might help in preventing the entry of aerosols of size as small as PM 2.5 and PM 10. The ventilation system should be optimized in such a way that the wind is directed away from the people and should not be mixed with the air in a public area. All these measures can help in reducing both droplet contacts and exposure to aerosol particles. They further stated that more research needs to be done to find out more about the evaporation of SARS-CoV-2 virus droplets. For more information, read our article on How to protect yourself against COVID-19 infection. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.