On February 11, 2020, four "senior medical practitioners" signed off on an advisory urging Singaporeans to wear masks even if they're well.

Mothership reached out to one of the signatories, Colleen Thomas, and confirmed the veracity of the letter.

Thomas, who is a doctor at Saint Jude Centre for Internal Medicine, told Mothership that the letter had only been sent out to their immediate friends yesterday.

Despite that limited initial circulation, the letter has reached out to a significantly higher number of people in just one day.

A phenomena used by Thomas to describe how viruses spread.

According to Thomas, the four doctors are NUS classmates.

Two of the other signatories are apparently general practitioners from Bendemeer and Farrer Park.

The last doctor has relocated to Australia but, according to Thomas, often comes back to Singapore.

Their advisory advocates two main actions.

Always wear a mask when outside, and reduce mingling. The advisory also called on for creative means to make up for any potential shortfall in surgical masks.

One of their suggested steps include always wearing a mask since it provides "two barrier protection".

The four insist that they are not trying to "disclaim" the authorities but felt the professional need to disseminate the message.

Other measures include not dwelling in air-conditioned places for too long, schools conducting online lessons, and using online delivery services.

Here is the letter.

During the ministerial taskforce press conference on Feb.12, Director of Medical Services Kenneth Mak addressed the topics of letters floating around social media.

"We are aware that there are various letters, emails, WhatsApp messages sent on social media, all with good intentions, by a variety of different people, including doctors.

And they are all well intentioned in order to encourage members of the public to engage in good activities to protect themselves.

And some of the advice in fact is very relevant, and that includes advice, instructions, to wash your hands, but it is important to remember that this infection, this virus, is spread by droplets or contamination of surfaces.

There is no established evidence that in the open, this virus spreads by the air, or aerosolisation.

The best advice I can give you is to defend yourself is washing your hands regularly, frequently, with soap and water, and also to be mindful of things you commonly touch.

The most common thing that you touch is your phone, and you might want to make sure that you clean the surfaces of the phone as you touch it.

Subconscious, we often do that, but these are our important things to make sure you protect yourself.

It is not wearing masks that's most important, it's hand washing."

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