Researchers from Department of Microbiology of HKU confirms that surgical masks can effectively reduce infection rate of COVID-19 by 41.7%


17th May 2020 – (Hong Kong) Dr. Yuen Kwok-yung, microbiologist, physician and surgeon from University of Hong Kong announced today (16th) that wearing surgical masks can effectively reduce the infection rate of COVID-19 by 41.7% and is of great significance to the infection control strategy of the epidemic. Dr.Yuen’s experiment showed that it is very important for all people to wear masks. Even if the way of wearing masks may not be completely correct, it can still effectively reduce non-contact transmission, especially in closed environments. He also recommended that people with symptoms to go to designated clinics to get deep throat saliva test to ensure that Hong Kong maintains a low level of diagnosis.

Researchers from the Department of Microbiology of the University of Hong Kong established the world’s first golden Syrian hamster model against the new coronavirus (COVID-19). They placed the hamster with the new coronavirus and another batch of virus-free hamsters in different cages. The fan creates a unidirectional airflow, and the two cages are separated by a perforated partition so that the unidirectional airflow can enter the other cage from one cage through the partition, and then a surgical mask is placed between the two cages to separate the two. The first group involves two batches of hamsters not separated by a surgical mask, the second group involves cages with virus-infected hamsters separated with mask simulating sick people wearing masks, the last group is virus-free hamsters with cages separated by mask, which simulates the wearing of masks by people who are not sick. In addition to the clinical score, the team also tested the number of viruses in the hamsters, pathological changes, and the number of viral nucleocapsid antigens.

The results showed that the infection rate of non-virus-infected hamsters without contact transmission was 66.7% when no surgical mask was used, in the second group, the infection rate of virus-free hamsters was significantly reduced to only 16.7%. When virus-free hamsters were separated by surgical mask, only 33.3% were infected. From the research, it can be seen that wearing a surgical mask can effectively reduce this non-contact transmission, especially when the infected person wears a mask. Dr.Yuen said that in the group of hamsters infected by non-contact infection, the clinical signs and pathological changes of the groups separated by surgical masks were significantly smaller, proving that the use of surgical masks can significantly reduce the non-contact transmission rate of COVID-19 and the severity of the epidemic. The research results will be published in the international scientific journal “Clinical Infectious Diseases”.