Holding breath near Covid patients ups infection risk

Holding breath near Covid patients ups infection risk

TIMES NEWS NETWORK

Chennai:12.01.2021

If you thought holding your breath or breathing slower could protect you from Covid infection when you pass by an individual with or without a mask, think again. A study by IIT Madras has found holding your breath or breathing slower in front of a Covid positive person may only increase the risk of contracting the infection.

A team from the department of applied mechanics modelled the breathing frequency in a laboratory and found that the slower and deeper a person breathes, the greater the chance of the virus depositing deep in the lung.

When you breathe slower, the aerosol particles stay longer inside the lungs and the changes are greater that they will reach and deposit deep in the lung, said Prof Mahesh Panchagnula, who led the research team of Arnab Kumar Mallik and Soumalya Mukherjee.

“The morphometry and bronchioles of lungs as well as breathing pattern varies with individuals. So, it is hard to control that. But it affects the deposition rates,” he added.

Researchs globally found coronavirus spreads mostly through tiny droplets released when an infected person sneezes or coughs. The IITM team replicated the droplet dynamics in the lung by studying the movement of droplets in the small capillaries or blood vessels which were similar in size to bronchioles or air passages in the lungs.

For the study, they mixed fluorescent particles in water and generated aerosols from it using a nebulizer. The aerosols were then tracked for movement and deposition in the capillaries with a diameter of 0.3mm to 2mm.

The scientists found that when the aerosol movement is steady, the particles deposit in the lung by chance, but when movement is turbulent they deposit upon impact.

In an earlier work, the group also studied the variability in aerosol uptake from individual to individual, suggesting a reason why some people are more susceptible to airborne diseases than others. “The core motivation of this work is to understand why some people are more susceptible to airborne disease than others. There’s a biological immunity aspect to it but there is also a lung morphometry which could be different in some people, causing one person to be slightly more susceptible to infection than others,” Prof Panchagnula said.

“In some other related work, we found that the efficacy of wearing a mask is very good. If a Covid positive person wearing a mask coughs or sneezes, the aerosol production rate goes down by almost a factor of 1000. The mask also protects you from the large droplets produced when a person sneezes or coughs. It cuts both ways,” he said.

Indian Medical Assn asks docs to get vaccinated first to show it’s safe

Chennai: The Indian Medical Association has urged its 3.5 lakh members from 1,800 local branches to get vaccinated first to show to the world that Covid-19 vaccines are safe and effective. The health ministry has announced that the country’s vaccination drive against Covid-19 will begin on January 16. Three crore health and frontline workers will be inoculated in the first phase. In a statement on Monday, IMA national president Dr J A Jayalal said the association had decided to actively take part in Covid-19 vaccination programme after extensive review of scientific data, indexed articles, expert panel reports and in consultation experts. “Good protective levels of antibodies have been found to develop with our Indian vaccines against current and new mutated strains. The IMA believes getting vaccination is not only to protect individuals but also to bring herd immunity to the community, raising the hope to control the corona pandemic,” he added. The association headquarters in New Delhi has constituted a pharmacovigilance centre for monitoring post vaccination reactions and rendering appropriate support. TNN