Masks, not stopping breath, best way to prevent Covid-19 infection: IIT-Madras study

A study by the Indian Institute of Technology Madras (IITM) has found that the process of transporting Sars-CoV-2-laden saliva droplets deep inside the lungs of an individual increases if they hold their breath. The Sars-Cov-2 virus causes Covid-19.

A study by the Indian Institute of Technology Madras (IITM) has found that the process of transporting Sars-CoV-2-laden saliva droplets deep inside the lungs of an individual increases if they hold their breath. The Sars-Cov-2 virus causes Covid-19.

A health worker collects swab sample of a resident at Goregaon (West) in Mumbai on Monday. (Satyabrata Tripathy/ HT PHOTO)

Led by professor Mahesh Panchagnula from IITM’s department of applied mechanics and consisting of research scholars Arnab Kumar Mallik and Soumalya Mukherjee, the research team modelled breathing frequency in a laboratory. Their findings show that low breathing frequency increases virus’s time of residence therefore increases the chances of deposition and consequently infection in an exposed individual. The results of the study were published in November 2020, in the reputed peer-reviewed journal, Physics of Fluids.

The researchers said the study shows how different dimensions of lungs effect an individual’s susceptibility to Covid-19. “Covid-19 has opened a gap in our understanding of deep pulmonological systemic diseases. Our study unravels the mystery behind how particles are transported and deposited in the deep lung. The study demonstrates the physical process by which aerosol particles are transported into the deep generations of the lung,” said Panchagnula.

Explaining their laboratory model, Panchagnula said, “We have been consistently studying and understanding the mechanics of breathing lungs. Infections like Covid-19 spread through sneezing and coughing as they instantly release droplets. Our team simulated the droplet dynamics in the phantom model of a lung by studying the movement of droplets in the small capillaries, which were of a diameter similar to the bronchioles.” Water was mixed with fluorescent particles and aerosols generated from this liquid were used with the help of a nebulizer for the experiments. “These fluorescent aerosols were used to track the movement and deposition of particles in the capillaries,” he said.

Panchagnula said the science shows wearing masks in public spaces is advantageous as a protection against infection. “Use of masks not only contains the infection-laden droplets from an infected person, but also ensures others don’t come in contact with these droplets,” he said.

Apart from focus on the effect of diseases like Covid-19 on lungs, the IITM study also paves the way to develop better therapies and drugs for respiratory infections.