Scientists have tested 14 different types of face-covering and found that one of them actually increases the risk of coronavirus infection.
Researchers at Duke University in North Carolina tested coverings ranging from the kind worn by healthcare professionals to neck fleeces and knitted masks.
The study’s authors compared the dispersal of droplets from a participant’s breath while they were wearing one of the coverings to the results of a control trial where their mouth was fully exposed.
The least effective face-covering in the study was a neck fleece which was found to actually increase the risk of infection by having a “droplet transmission fraction” of 110%.
Duke University researcher Martin Fischer, who put the test together, told CNN: “We were extremely surprised to find that the number of particles measured with the fleece actually exceeded the number of particles measured without wearing any mask.
“We want to emphasise that we really encourage people to wear masks, but we want them to wear masks that actually work.”
