After a much debate on the efficacy of masks in combating Covid-19, there seems to be growing consensus that a protective gear covering mouth and nose can be highly effective in checking the spread of the virus.

Underscoring the import of short-term behavioural changes like wearing of masks to restrict the spread of Covid-19, experts say a week after exposure, a millilitre of saliva of a Covid-19 patient can be laden with as many as a hundred million viral particles.

A mere 40-200 strands of the microbe are good enough to infect a healthy person.