COVID-19: Maintain 20 feet distance from people to avoid infection

The current guideline of maintaining a 6 feet distance from the next person to avoid COVID-19 infection may no longer hold true. A new study says that 20 feet is the new minimum.

Social distancing is one of the ways by which you can prevent the spread of COVID-19 and keep yourself safe. But along with it you also have to practice the other guidelines laid down for the purpose. Frequent washing of hands, good respiratory hygiene and avoiding crowds also go a long way in containing the spread of the virus that causes this highly contagious viral disease. Now with the easing of lockdown restrictions, it becomes very important to be conscious of all the precautionary methods. This disease may be around for a long time. There is as yet no vaccine that can keep you safe. So, you need to follow precautions that will keep you safe. Also Read - COVID 19 transmission: Don’t let this infection in through your eyes

That is why, the findings of a recent study on social distancing is a cause for worry. Till now experts were of the opinion that maintaining a distance of 6 ft is enough to be safe from the virus. But now a study at the University of California and Stanford University, US, says that this may not be enough as the virus can travel as far as 20 feet. This study is not yet published and is under peer review. Also Read - COVID-19 in India: Over 6,000 cases reported every day, recovery rate rises to over 42 %

Six feet apart was the norm till now

Till now government guidelines said that you must maintain a distance of 6 feet from the next person to be safe from the COVID-19 virus. Even the Centers for Disease Control in the US and the Ministry of Health and Family Welfare in India kept this as part of their safety guidelines. All countries and organisations across the world said that everybody must maintain a minimum distance of 2 metres or six feet whenever they step out in public. This is 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. Also Read - Countries halt hydroxychloroquine trials as WHO raises safety concerns over its use in COVID-19 treatment

Spreading ability of virus changes with weather

Researchers of the above-mentioned study created a mathematical model to test the spreading ability of airborne droplets in different environmental conditions such as a change in temperature, humidity and wind velocity. They tested the projectile motion and the evaporation of the viral droplets. They saw that as the weather changes, the spreading ability of the virus also changes. In dry and hot weather, the droplets convert into aerosols, which can transmit the infection to a longer distance. 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, they say. In cool and humid weather, researchers saw that the aerosol production reduces but the infection kept on spreading in the form of droplets. In such weather conditions, they recommend a minimum distance of approximately 20 feet between people to prevent transmission of COVID-19.

Ventilation too plays a role

Researchers also found that ventilators are helping the transfer of both infectious droplets and aerosol particles to a longer distance. They say that the improper use of ventilators in public spaces work in favour of the virus and make transmission easier. This is especially true a humid and hot environment.

Maintain a distance of 20 feet to be safe

Researchers say that the current guidelines must change to accommodate the new findings. But they also say that wearing a face mask properly will help in preventing the entry of aerosols of size as small as PM 2.5 and PM 10. They also recommend that ventilation system must be optimized in such a way that the wind is directed away from 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 maintain. But they also add that more research is required before anything can be said conclusively.