9th July 2020
A report by the Oxford Leverhulme Centre for Demographic Science investigated the effectiveness of different face mask types and coverings and also compared international policies and behavioral factors that would underly mask usage.
Published in joint with the British Academy and the Royal Society as part of the society's SET-C group, Professor Melinda Mills, the author of the study said that masks were essential in reducing viral transmission and protecting people, and noted in the study that most countries made their use mandatory with a few discrepancies.
The study agreed that cloth face coverings, including homemade ones, were effective in reducing the spread of COVID-19 for the wearer and those around them provided the correct material was used.
The study looked at a timeline since the World Health Organisation announced the pandemic in mid-March and noted how nearly 70 countries immediately recommended mask-wearing to their populations.
The study highlighted how countries that were affected by earlier SARS outbreaks, particularly in ASIA, saw early and nearly universal mask usage.
Some of the key findings of the study highlighted by IOL are as follows:
Cloth face coverings are effective in protecting the wearer and those around them.
Behavioral factors, including how people understand the virus and their perceptions of risk, trust in experts, and government, can adversely affect mask-wearing.
Face masks are part of ‘policy packages’ that need to be seen together with other measures such as social distancing and hand hygiene.
Clear and consistent policies and public messaging are key to the adoption of wearing face masks and coverings by the general public
Professor Mills noted how inconclusive scientific evidence about the effectiveness of masks in contrast to recommendations made by the WHO may have confused the public, and that clear advice was necessary o what type of masks to wear, when to wear them and how to wear them to ensure maximum possible safety.
As for the main point, the study found that loosely woven fabrics such as scarves were the least effective as protective equipment.
Mills noted that a good fit on the face was necessary and, looping around the ears or the back of the neck for better coverage was the best way to ensure a close fit.
"The general public does not need to wear surgical masks or respirators. We find that masks made from high quality material such as high-grade cotton, multiple layers and particularly hybrid constructions are effective. For instance, combining cotton and silk or flannel provide over 95 percent filtration," concluded Mills.