While a recent study claimed dining out and shopping could be more dangerous than air travel during the COVID-19 pandemic, in part because of special ventilation systems on planes, some scientists say such a comparison cannot be made without knowing whether the mask- wearing and social distancing standards are correctly followed in each of these scenarios.
In research, funded by airlines, airports and aircraft manufacturers, scientists at the Harvard TH Chan School of Public Health in the United States, said that the aircraft ventilation system uses High Efficiency Particulate Air (HEPA) filters circulated continuously and refreshed the air supply. , “Filter more than 99% of the particles responsible for COVID-19”.
However, researchers, including Arnold I Barnett of the Massachusetts Institute of Technology (MIT) in the United States, said HEPA filters may not work as efficiently in airplanes as the report suggests.
“HEPA filters are very good, but not as effective as US airlines suggest. They are not foolproof and there are many examples of transmission despite these filters,” said Barnett, a professor of statistics specializing in problems with health and safety. .
He noted that the likelihood of transmission depends on the virus emissions from an infectious passenger through breathing, speaking and coughing or sneezing – a mixture that varies from person to person – as well as the movement of the droplets. and aerosols given the geometry of the aircraft. and its powerful HEPA air purification systems.
“None of the processes are fully understood for COVID-19,” the MIT scientist noted.
Abraar Karan, of the Department of Medicine at Harvard Medical School in the United States, also expressed concern about the risk of transmission on airplanes.
“For those planning to fly, the reality is that while planes have excellent ventilation systems, we don’t have a good idea of how many COVID-19 cases actually get infected on the flight itself,” he said. Mr. Karan tweeted.
“We are not testing the right way to figure this out,” he added.
Commenting on the risk of contracting COVID-19 on airplanes versus the odds in grocery stores and restaurants, Justin Yang of Harvard TH Chan School of Public Health, who was unrelated to the study, said that such an assessment “cannot be done in a simple manner.”
Yang, whose team recently published a study of COVID-19 infection among grocery workers at a retail outlet in the United States, said, “There isn’t really any order. safer-risky situations between planes and grocery stores as it depends on many factors. “
“It ultimately depends on how far away you are from an infected person. The closer you are to an infected person, the more likely you are to be infected, ”he told PTI.
The public health researcher added that the risk on airplanes is “not as great as people think,” due to airflow patterns, improved cleaning and mandatory mask wear.
“However, if you are sitting right next to an infected person, there is a significant risk of getting infected,” Yang added.
According to him, to compare the risk scenarios, it is necessary to know whether the measures of social distancing and wearing of masks are applied adequately in the respective contexts.
According to the MIT researcher, removing masks for long periods of time in each of the settings – grocery stores, restaurants and airplanes – “mitigates the benefits of wearing a mask.”
Based on his team’s yet to be peer-reviewed study, he said removing masks to consume food offered on commercial planes could significantly increase the risk of passengers are infected with the virus.
If a person on a two-hour plane trip takes off their mask for about 20 minutes, Barnett said “it increases the risk of transmission by 33 percent.”
“Masks reduce the risk of transmission by about two-thirds. If X is the risk of transmission over 20 minutes with a mask, and therefore 3X without a mask, then the total risk is about 6X for a two-hour flight, and 8X (ie 5X + 3X) with a 20 minute mask break. The ratio of 8X to 6X is 1.33. Of course, that’s an approximation, “he said. he explains.
While the risk of death for domestic air passengers who contract COVID-19 may be lower than the average for the U.S. population, Barnett and his team said COVID-19 infections on airplanes can lead to the death of some people. who were not passengers.
“These indirect victims of infections that occurred during flights (ie tertiary infections) may well outnumber the direct victims,” he noted.
(This story was not edited by GalacticGaming staff and is auto-generated from a syndicated feed.)