Double masks substantially reducing exposure to virus: Research

Washington, Feb 11 : The US Centers for Disease Control and Prevention (CDC) has recently conducted experiments to improve the fit of masks amid Covid-19 pandemic, suggesting that combining cloth mask and medical procedure mask could reduce a wearer’s exposure to virus by over 90 per cent.
In January, the CDC conducted experiments to assess two ways of improving the fit of medical procedure masks: fitting a cloth mask over a medical procedure mask, and knotting the ear loops of a medical procedure mask and then tucking in and flattening the extra material close to the face, the Xinhua news agency reported.
Each modification substantially improved source control and reduced wearer exposure, according to a report released by the CDC on Wednesday.
“Based on experiments that measured the filtration efficiencies of various cloth masks and a medical procedure mask, it was estimated that the better fit achieved by combining these two mask types, specifically a cloth mask over a medical procedure mask, could reduce a wearer’s exposure by over 90 percent,” said the report.
These laboratory-based experiments highlight the importance of good fit to optimise mask performance.
Until vaccine-induced population immunity is achieved, universal masking is a highly effective means to slow the spread of SARS-CoV-2 when combined with other protective measures, such as physical distancing, avoiding crowds and poorly ventilated indoor spaces, and good hand hygiene, according to the CDC.