New research in Hong Kong re-confirms that the use of face masks can stop the spread of COVID-19 — even for hamsters.

Everyone is understandably anxious to get out of the house and resume normal life. But the coronavirus hasn’t left, not at all, and resuming normal life means we have to take precautions. The wide-scale use of face masks is the simplest and most effective step we can take towards ensuring public health. And hamsters are helping prove its worth.

Safely masked

“It’s very clear that the effect of masking the infected, especially when they are asymptomatic — or symptomatic — it’s much more important than anything else,” Yuen told reporters Sunday.

“It also explained why universal masking is important because we now have known that a large number of those infected have no symptoms.”

The team claims that their research (not yet published) is the first to test whether masks specifically can stop COVID-19, both symptomatic and asymptomatic, from infecting other individuals.

The authors infected healthy hamsters with the virus and placed these animals in containers. In another container connected to the first one, they placed a healthy hamster, thus creating an opportunity for infection. A fan was used to blow air from the infected animal’s container into the neighboring one.

Then, they placed a surgical face mask in the space connecting these two in order to filter all airflow between them.

According to the results, two-thirds (10 out of a 15 total) of the healthy mice were infected within a week without the masks set in place (and without any direct physical contact between the healthy and unhealthy). However, after the masks were installed, transmission rates went down by as much as 75%.

The findings have been detailed on the Hong Kong Today show and in the South China Morning Post. According to the SCMP,” only two of 12 subjects in the adjoining cage” (16.7%) tested positive for the coronavirus when masks were placed on the infected hamster’s box. When the masks were applied only to the cage with healthy hamsters, 4 out of 12 (33%) became infected.

“Transmission can be reduced by 50% when surgical masks are used, especially when masks are worn by infected individuals,” Professor Yuen explained for SCMP.

Furthermore, hamsters that did become infected during the masked experiments showed lower levels of the virus within their body than those infected without a mask.