Is double masking necessary in Bengaluru?

The observation about its efficacy is based not on statistics but on a recommendation by the American national health agency

Last month the Centers for Disease Control and Prevention (CDC) put out an advisory recommending double masking (layering a close-fitting surgical mask with cloth masks) as an effective method to slow the spread of Covid-19. It was first endorsed by Dr Anthony Fauci, who said, “it just makes common sense”.

According to findings from a CDC study, wearing a cloth mask on top of a surgical mask helps improve the fit of the surgical mask.

The closer the mask fits your face, the fewer gaps there are between the mask and your face where respiratory droplets carrying the coronavirus can enter.

The study found, “The receiver’s exposure was maximally reduced (>95%) when the source and receiver were fitted with modified medical procedure masks.”

This CDC study compared wearing no mask, a poorly fitted surgical one, cloth-only mask and double-masking in a simulation of respiratory droplets between two people — a source and a receiver — to come to its conclusion.

With cases in the country increasing daily, Metrolife reached out to doctors in the city to see if they recommend double masking to the citizens.

Effective protection

Dr Srivatsa Lokeshwaran, consultant interventional pulmonologist, says that double masking is an easy way to increase protection against the virus. “Layering the mask helps to improve the face fit and reduce the space available for the virus to sneak through,” he says.

Medical procedure masks block the aerosols to the tune of 56 per cent and cloth mask alone block aerosols by 51.4 per cent, compared to the 90 per cent when double masking. “Recent studies found that mask fitters improve the protection level of the masks by 90 per cent. Hence, in simpler terms by combining a cloth mask over a medical procedural mask we can improve protection by 90 per cent,” he says.

The study did not look at the effectiveness of respirators, like N95s, in comparison. “N95 are medical-grade masks meant to filter out 95 per cent of fine particles and they are always superior to cloth masks and even double masks. However, these respirators continue to be reserved for medical personnel, who are at higher risk,” he says.

However, he agrees that there can be some drawbacks. “It can be cumbersome for children and people who already feel suffocated from wearing just one mask,” he says. Along with double masking, people should continue to adopt the habit of handwashing and adhere to the social distancing norms until widespread vaccination has been achieved, he adds.

Need more evidence

Dr Aravinda G M, consultant, internal medicine, says that the rise in cases can be attributed to many factors including change in the viral strain, and human factors such as, not following covid appropriate behaviour of wearing a mask, maintaining social distance, etc. “While a lab study in the US suggests that double masking may reduce infection rates, there is no large, population-based evidence yet,” he says.

While double masking is not without benefits in terms of reducing the overall Covid-19 disease burden it has its drawbacks. For one, he says, it would be uncomfortable and impractical in hot and humid conditions as in various parts of India. “A few random experiments conducted on dummies show that wearing two masks is practically a challenge. The masks slide up or down with jaw movement, and two masks end up collecting more aerosols between them in comparison to when one wears a single mask,” he explains.

It is still too early for the government to mandate double masking, he adds.

For crowded spaces

Dr C Nagaraj, director of RGICD, says that double masking might prove to be effective in public transport and other crowded places or areas with poor ventilation, where the chances of contact with the infection are higher and that the government could mandate its use only in such areas. “It can also maybe prove to useful for sanitation workers, or healthcare workers, who come into contact with patients,” he says.

However, he does not think the current climb in cases calls for double masking to be made mandatory. “Sure, there is an increase in cases, but not like in the US, where the infection rate is climbing,” he says. However, double masking could help prevent the numbers from climbing further.

Wear one right

Dr Ravindra Mehta, chief pulmonologist, says that the idea of double masking is solely dependant on the idea that two is better than one, and hence is a more intuitive idea than a scientific one. “It is not a data-driven conclusion, and it is mere speculation,” he says.

While in areas with higher cases it might seem smart to take up the practice, the current rise in cases in the city doesn’t warrant it, he says. However, even if the practice were to be adopted, double masking would only prove effective if both masks are worn properly. “Only 30- 40 per cent of people in the country wear the one mask as mandated properly. So, how will wearing two improve? The focus, for us, should be on getting people to wear that one mask the right way,” he says.

Latest regulations

As cases in the country continue to spike, the Government of Karnataka put out a new set of guidelines on March 24. The order has reiterated that citizens wear masks and maintain social distancing, and failure to do so will lead to a fine of Rs 250 in BBMP and Municipal Corporation areas and of Rs 100 in non-Municipal Corporation areas. Owners of premises for weddings, funerals, and any other gatherings, as per the order, will be held responsible for ensuring that Covid protocols including ensuring that restrictions on the number of people allowed to gather are followed. Failure to comply can attract a fine of up to Rs 10,000.