Researchers at the Indian Institute of Technology Madras have found that when breathing frequency falls, the chances of virus-laden droplets being transported deeper into lung increases.
A team of researchers modeled breathing frequencies in the lab and found that in persons with low breathing frequency, the virus lives longer and increases the chance of deposition resulting in infection. Also, the multi-scale lung structure has a significant effect on a person’s susceptibility to COVID-19.
The research was led by Mahesh Panchagnula, Department of Applied Mechanics and his research scholars Arnab Kumar Mallik and Soumalya Mukherjee and the findings were published in the international peer-reviewed journal Physics of Fluids.
Mr. Panchagnula said: “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.”
In their research, the team reported that holding the breath and having low breathing rate can increase chances of virus deposition in the lungs. The study was conducted to pave the way for developing better therapies and drugs for respiratory infections. In an earlier work the team had highlighted that there was significant variability in aerosol uptake among individuals, suggesting why some people are more susceptible to airborne diseases.
The research team imitated the droplet dynamics in the lung by studying the movement of droplets in the small capillaries of size ranging from 0.3 to 2 mm, a diameter similar to bronchioles. They took water mixed with fluorescent particles and generated aerosols from the liquid using a nebuliser. The fluorescent aerosols were used to track the movement and deposition of particles in the capillaries.
The team intends to continue this work to understand how the virus-laden droplets are transported into lungs. The process by which the virus is transported from the nasal cavity to the deep lung is yet unknown. An understanding of the physics of this phenomenon could be crucial in mitigating the progression of the disease, the team has said.
