Researchers at the University of Hong Kong recently conducted a rigorous experiment on hamsters to demonstrate how surgical masks curb COVID-19 spread. This pioneering study is one of the first to quantify whether masks prevent both symptomatic and asymptomatic individuals from infecting others.
Mask-wearing sparked intense debate in the UK, with a Royal Society report affirming its benefits for the general population. Experts noted that masks could significantly reduce transmission from asymptomatic and pre-symptomatic carriers. Critics, however, warned of potential downsides, such as reduced adherence to other precautions like distancing and hygiene.
Debate also surrounds mask types. While FFP2 or surgical masks are ideal, even homemade options offer some protection by limiting droplet dispersal—as highlighted by pulmonologist Bertrand Dautzenberg amid April controversies.
As reported by the South China Morning Post on May 17, 2020, Professor Yuen Kwok-yung and his University of Hong Kong team tested surgical masks on about fifty hamsters. In a controlled setup, cages with one infected hamster were placed near those with three healthy ones, aided by ventilation to mimic airborne transmission. Without barriers, the infection rate reached 66.7%.
Repeating the experiment with surgical mask barriers yielded striking results: transmission dropped to 15% when barriers were on infected hamsters' cages and 35% on healthy ones.
Professor Yuen concluded that surgical masks are highly effective, with optimal protection when worn by infected individuals—including undetected asymptomatics who drive silent spread.
