The two main sources of transmission of coronavirus are through contact and respiratory droplets, according to the latest advice from the World Health Organisation (WHO). That suggests properly worn face coverings are likely to slow or prevent the spread of Covid-19 to those at risk of inhaling a respiratory droplet from an infected person.
There is also advice to suggest by wearing a mask, an infectious person greatly lowers their risk of transmitting the virus to others.
In the US, the Centres for Disease Control and Prevention (CDC) are urging people to cover their faces with homemade masks.
After these guidelines were announced in the US, President Donald Trump said in a media briefing the cloth coverings were being recommended but remained "voluntary".
"I'm choosing not to do it, but some people may want to do it and that's OK," Trump said at the start of April.
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Masks are also not being recommended by New Zealand authorities, who have advised there is not sufficient evidence to suggest wearing a mask stops the spread of the coronavirus in healthy populations.
Some leaders, however, are less hesitant to take on the practice, including Slovakian president Zuzana Caputova, who has attracted attention online for co-ordinating her masks with her outfits.
Japan's Prime Minister Shinzo Abe was also seen wearing a mask as he announced a nationwide state of emergency in the country.
A number of other global politicians have also shared images of themselves in face masks including the Greek Prime Minister, New York City congresswoman Alexandria Ocasio-Cortez and the Democratic governor of Michigan, Gretchen Whitmer.
A new report suggested mask wearing had also become partisan in Washington, with Politico reporting, "Wearing a mask is for smug liberals. Refusing to is for reckless Republicans", on Friday.
The World Health Organisation (WHO) has remained reticent on broadly recommending the public wear face masks. While the global health body conceded at the beginning of April masks are one effective preventive measure, they remain steadfast in recommending all masks "should be reserved for health care workers".
The WHO does not advise healthy people wear masks, but should instead practise social distancing, practise hand hygiene, refrain from touching their face and cover their mouth and nose with their elbow when coughing or sneezing.
• Covid19.govt.nz: The Government's official Covid-19 advisory website