(Reuters) – As the coronavirus began to spread around the world, a global shortage of masks and other protective equipment emerged, especially for frontline medical staff.

How those supplies are used is crucial, experts say.

Based on current evidence, SARS-CoV-2, the virus that causes COVID-19, is most frequently transmitted between people via droplets when an infected person breathes out, coughs or sneezes, and can also spread via contaminated surfaces such as door handles.

For the general public, basic preventive measures include keeping a safe distance of 1 to 2 metres, washing hands with soap for 20 seconds or using a hand sanitiser, wearing a face mask if crowded situations cannot be avoided and not touching one’s eyes, nose, and mouth.

In hospitals and other frontline medical scenarios, however, the guidelines are much more complex – and the personal protective equipment (PPE) much more robust.

The World Health Organization (WHO) has issued specific recommendations for these situations, aimed at both protecting workers and preserving gear for where it is needed most.

For a graphic of the WHO’s guidelines for PPE use among frontline medical staff, open https://graphics.reuters.com/HEALTH-CORONAVIRUS/PPE/rlgpdwxkavo/index.html in an external browser.

By May 7, Reuters data showed more than 3.5 million people worldwide have been infected by the coronavirus and 256,053 have died of the disease it causes, COVID-19.

(Writing by Gerry Doyle; Editing by Clarence Fernandez)