According to the WHO, the two main routes of transmission of the deadly virus are respiratory droplets and physical contact.

Respiratory droplets are generated when an infected person coughs or sneezes. Any person who is in close contact (within 1 m) with someone who has respiratory symptoms (coughing, sneezing) is at risk of being exposed to potentially infective respiratory droplets.

Droplets may also land on surfaces where the virus could remain viable. Thus, the immediate environment of an infected individual can serve as a source of transmission (contact transmission).

Wearing a mask can reduce the potential risk in a large extent.

Earlier WHO argued that there was not enough evidence to say that healthy people should wear masks.

Some countries around the world already recommend or mandate the wearing of face masks in public.

WHO on Friday issued a guideline on how to wear masks properly maintaining healthcare. It said appropriate use and disposal of masks are essential to ensure that they are effective and to avoid any increase in transmission.

It suggested placing the mask carefully, ensuring it covers the mouth and nose. Besides, it should be tied securely to minimize any gaps between the face and the mask.

The person should avoid touching the mask while wearing it. Later, he or she should remove the mask using the appropriate technique - do not touch the front of the mask but untie it from behind.

After removal or whenever a used mask is inadvertently touched, one will have to clean hands using an alcohol-based hand rub or soap and water if hands are visibly dirty.

Damp masks should be replaced as soon as possible with a new clean, dry mask.

WHO also suggested avoid re-using single-use masks and asked to dispose of them immediately upon removal.