New Delhi: Laboratory experiments conducted by health officials in the US have revealed that the use of two masks is likely to significantly reduce a person’s exposure to the coronavirus.
According to a report published by the Centers for Disease Control and Prevention (CDC) Wednesday (10 February), two methods of wearing face masks could boost protection against Covid-19. The first method is wearing a cloth mask over a disposable surgical mask, and the second is wearing a well fitted single surgical face mask, by knotting the ear loops and tucking the sides in order to prevent air from leaking out.
Masks can reduce “exhaled respiratory droplets and aerosols” from those who are infected, the report noted.
In January 2021, CDC had conducted experiments using a pliable elastomeric (rubber-like property) source to figure out the extent of the two modifications on masks. The report revealed that the two methods mentioned above reduced exposure to the coronavirus by at least 95 per cent in a lab experiment that used dummies. And the combination of the cloth mask over a surgical mask blocked 92.5 per cent of cough particles, the report noted.
“Results from the first experiment demonstrated that the unknotted medical procedure mask alone blocked 42 per cent of the particles from a simulated cough, and the cloth mask alone blocked 44.3 per cent,” the report said.
It also recommended that until vaccine-induced immunity is achieved, wearing masks can prove to be highly effective in containing the spread of coronavirus.
Also read: Experimental hepatitis drug speeds up Covid recovery by 4 times, finds Toronto study
‘Findings must not be generalised’
The report also said knotting and tucking a medical procedure mask reduced exposure by 62.9 per cent. When an infected person was unmasked and a receiver was wearing a double mask or a knotted one, the latter’s exposure was reduced by 83 per cent and 64.5 per cent respectively.
Further, when the infected person and receiver were both wearing double masks or knotted ones, the exposure was reduced by 96.4 per cent and 95.9 per cent respectively.
John T.Brooks, medical officer for Covid-19 response at the CDC, said, “We know that universal masking works. And now these variants are circulating…whatever we can do to improve the fit of a mask to make it work better, the faster we can end this pandemic.”
The report, however, mentioned limitations such as the experiments conducted with one type of medical procedure mask and one type of cloth masks only. It also warned that the findings must not be “generalised” as effective for different kinds of masks.
Also read: Pfizer vaccine can neutralise Covid variants first reported in UK, South Africa, study says