COVID virus is evolving, more efficient at becoming airborne: Study

New York: A new study has found that people infected with the Alpha variant exhaled 100 times more virus into the air than people infected with the original Covid strain.

A team of researchers at the University of Maryland School of Public health in the study stressed the need for better ventilation and tight-fitting masks, in addition to widespread vaccination to help stop the spread of the virus.

The findings showed that the amount of virus in the air coming from Alpha variant infections was much more -- 18-times more -- than could be explained by the increased amounts of virus in nasal swabs and saliva.

These major increases in airborne virus from Alpha infections occurred before the Delta variant arrived and indicate that the virus is evolving to be better at travelling through the air.

"We already knew that virus in saliva and nasal swabs were increased in Alpha variant infections. Viruses from the nose and mouth might be transmitted by sprays of large droplets up close to an infected person. But, our study shows that the virus in exhaled aerosols is increasing even more," explained Jianyu Lai, a doctoral student at the varsity.

While the study, published in Clinical Infectious Diseases, focussed on the Alpha variant and original strain of the virus, the researchers believe that the Delta variant is even more transmissible.

"We know that the Delta variant circulating now is even more contagious than the Alpha variant. Our research indicates that the variants just keep getting better at travelling through the air, so we must provide better ventilation and wear tight-fitting masks, in addition to vaccination, to help stop the spread of the virus," said Dr Don Milton, Professor of environmental health at the University's School of Public Health.

To test whether face masks work in blocking the virus from being transmitted among people, the study measured how much SARS-CoV-2 is breathed into the air and tested how much fewer virus people sick with Covid-19 exhaled into the air after putting on a cloth or surgical mask.

Face coverings significantly reduced virus-laden particles in the air around the person with Covid-19, cutting the amount by about 50 per cent. Unfortunately, the loose-fitting cloth and surgical masks didn't stop the infectious viruses from getting into the air.