Faculty of Nursing infection control expert looks at the truth behind the (homemade) mask

Apr 15th, 2020

Marcia Porter

Dr. Donna Moralejo
Faculty of Nursing infection control expert looks at the truth behind the (homemade) mask

Dr. Donna Moralejo arrived home from a month in Antarctica just as the COVID-19 virus was putting countries around the world into lock down.

The Faculty of Nursing’s associate dean (graduate programs) had been without internet connection for most of her time away, and returning to a world that was dealing with a global pandemic was a bit of a shock.

That’s in spite of her background as a nurse, epidemiologist and microbiologist in a career with plenty of experience working to strengthen infection prevention and control practice, which is a key component of preparing for epidemics.

“You are always aware of the potential for huge outbreaks and you always think it might come,” she told Ramona Dearing, host of CBC Radio’s Cross Talk recently. “But like everyone else, I find it hard to believe it’s actually happening.”

Family members wearing homemade masks

 PHOTO: SHARON MCCUTCHEON

Dr. Moralejo was invited on CBC Radio’s daily call-in show to talk about the use of homemade face masks. After a little preamble, the show’s host asked her the question of the day:

“Are you going to wear a face mask when you go out of the house Dr. Moralejo?”

“For this one I’m looking at Dr. (Theresa) Tam’s (Canada’s Chief Health Officer) guidance,” she answered. “Wearing a homemade face mask helps to protect others from you rather than you from others. It doesn’t take the place of hand washing or two meters of physical distancing.

“Because I often have a tickle at the back of my throat so can’t be sure if I’m carrying any viruses, I will wear one out in public when I cannot maintain the two meters of physical distancing.”

Protect others

Most of us have seen do-it-yourself (DIY) mask patterns on our social media feeds, and noticed people wearing them out in public. But how does that mask actually work, and who does it protect?

“Catching your respiratory secretions, the mask will help protect others from your droplets.”—Dr. Donna Moralejo

Though Dr. Tam and others stress that wearing a mask is about protecting others, confusion about the issue was reflected in calls to Cross Talk.

One caller said he was confused about why a non-surgical mask wouldn’t protect the wearer from potentially contracting the virus and Dr. Moralejo explained,

“First of all, there’s a little background that people need to understand about the mode of transmission,” she said.

“It’s in the respiratory secretions. We all expel some droplets of respiratory secretions when we cough or speak. They don’t travel very far and are quick to drop to the ground. That’s why you don’t want to be standing within two meters of someone.”

Dr. Moralejo pointed out that if someone is coughing, the density of the mask is not going to be enough to keep the droplets from entering your nose or mouth.

“That’s why it won’t protect you from others who have COVID-19,” she said.

However, the purpose of a homemade mask for the general public is to protect others from you.

“When you are talking and breathing, the droplets are smaller and fewer and they are caught on the inside of your mask,” she said. “Catching your respiratory secretions, the mask will help protect others from your droplets.”

Wash after use

She advised that masks should be washed after each use; it’s not only contaminated on the inside, but also on the outside from when you touch it because your hands are likely contaminated from touching things in the store or wherever you are.

“Start with a clean mask when you go out of the house, and be careful not to touch the front of it; handle it by the ties,” she said.

Fit is important

When another caller asked for advice on the best mask pattern to use, Dr. Moralejo was more concerned about the fit.

“You want a fit that covers your nose and mouth and that has as few gaps around your nose and mouth as possible. One with ties is more adjustable than one with loops around your ears.

She recommended two to four layers of breathable fabric, of tightly-woven material like what you’d find in a cotton t-shirt or pillowcase.

Dr. Moralejo reminded listeners that the best way to protect yourself against the virus is to heed what public health advises—maintain that two meter distance, wash your hands, don’t touch your face and stay home if you are sick