Study confirms masks slow spread of COVID-19

Czech chemist Vladimír Ždímal collaborated on an extensive international study on the effectiveness of face masks. A research paper published by the prestigious PNAS magazine confirms that face masks slow the spread of covid-19. Ždímal works at the Institute of Chemical Processes of the Academy of Sciences.

The international team of co-authors consisted of experts from various fields to get the most comprehensive picture of the issue. “In addition to the ability of different types of personal respiratory protective equipment to protect their wearer from infection, we also assessed epidemiological evidence, ecological studies, models of the spread of similar respiratory diseases, the results of experiments on population samples compared to control groups,” said Ždímal. According to him, the study also focused on the effect of wearing face masks on the psychology of the population during a pandemic. The final version of the article summarizes findings from more than 150 previously published works.

“By synthesizing all these works, we have come to the convincing conclusion that wearing face masks in public helps to effectively reduce the rate of pandemic spread, especially when worn by a high percentage of the population. Researchers also stressed the effectiveness of contact restrictions.

According to Ždímal, the study began in the spring. Experts previously published an earlier draft on the website Preprints.org. It already has hundreds of thousands of views.

Ždímal said that he was invited to join the team of authors at the turn of March and April as the only representative of the Czech Republic. The scientist is an expert in aerosol physics. His team from the Institute of Chemical Processes has been involved since March in testing the effectiveness of textile masks and respirators against covid-19 transmission.

According to the Academy of Sciences, the wearing of textile masks in public was recommended as early as 1910 by the Chinese physician Wu Lien Teh during the Manchurian plague epidemic. This recommendation is considered a milestone in the systematic fight against the spread of infectious diseases. However, textile protection of the mouth and nose against the spread of plague has been used since the 14th century.

Representatives of the AV also reported that cotton or silk, along with other fabrics such as chiffon and flannel, have recently been found to filter particles larger than 0.3 m with an efficiency greater than 96 percent.