Face masks vs coronavirus: How effective are they?

People wearing face masks in Hong Kong.
People wearing face masks in Hong Kong. © AFP / FRANCE 24

From expensive filtration devices to homemade coverings, face masks have become almost ubiquitous in Hong Kong in the wake of China's coronavirus outbreak. But experts say the choice of mask could make a big difference to its effectiveness.


Of the two main types of face masks on the market -- N95 respirators that fit tight to the face and include a filtration system, and the surgical face masks typically worn by hospital workers -- it is the latter that offers the best defence against the virus, says Joseph Kwan, professor at Hong Kong University of Science and Technology.

"Respirators are designed to protect the user, because they want to keep the contaminants out,” he told AFP. “[Surgical masks], actually in the healthcare environment are meant to protect the patients."

The World Health Organization has warned that the huge surge in demand for face masks and other protective clothing could lead to a shortage for those who need them most: doctors and nurses treating coronavirus patients.

Nevertheless, Professor Kwan argues they are essential in a crowded city such as Hong Kong.

"It will just spread like wildfire if nobody wears a mask, because you are not able to always identify infectious sources,” he said. “And then with the crowded conditions Hong Kong faces, then there will be many community cases. It will be a public health disaster."

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