Studies Dig Deeper Into Aerosol Transmission Of Coronavirus
People who suffer from obesity appear to exhale more, increasing their rate of potentially spreading covid; researchers are looking harder at air conditioning's role in the pandemic; the EPA now says handrails and doorknobs made with at least 95.6% copper can be marketed as "virus-killing."
COVID-19 Aerosol Load Associated With Infection, Age, Obesity
The number of COVID-19 aerosol droplets a person exhales is positively associated with infection, age, and obesity, finds an observational study published yesterday in the Proceedings of the National Academy of Sciences. The researchers looked at 194 healthy people to measure general aerosol rates as well as 8 COVID-infected nonhuman primates (NHPs) to look at how infection progression affected aerosol quantity and size. Human participants were asked to spend up to 30 minutes per session breathing into a mouthpiece connected to a particle detector. (2/10)
Fluid Dynamics Highlight Role Of Air Conditioning In Indoor COVID Spread
Computational fluid dynamics can help assess transmission risk of airborne COVID-19 particles, according to a study published yesterday in Physics of Fluids. The researchers, from the University of Minnesota, found that their modeling of a January 2020 COVID outbreak in a restaurant in Guangzhou, China, supports the idea that air conditioning contributed to disease transmission. After mapping out the general layout of the restaurant, its ventilation systems, and its occupants, the researchers discerned that the cyclical flow of air from the four heating, ventilation, and air conditioning (HVAC) units along the wall was disrupted by factors including hemispherical hot regions above each table due to food heat, the restaurant's occupants, and the presence of a fifth, floor-level HVAC unit on the adjacent wall. (2/10)
The Washington Post:
The Coronavirus Is Airborne. Here’s How To Know If You’re Breathing Other People’s Breath.
With its five wall-length windows, Nick Crandall’s restaurant, Railroad Pub & Pizza, can bring in a lot of outside air. In late December, though, Washington state regulators said the restaurant could not qualify as “outdoor” dining, and would have to close because of heightened coronavirus restrictions. So Crandall went to Facebook to protest, giving a video tour of the Burlington, Wash., pub and its vast, garage-door-style windows. “I’m just kind of curious on what the science is for outdoor dining, how much airflow you need to do,” he said. He took aim at the state’s Democratic governor, Jay Inslee, suggesting he use “common sense.” The video was viewed over 73,000 times. (Mooney, 2/10)
EPA Says Surfaces With Copper Alloys Can Fight COVID-19
Special copper doorknobs and handrails can help fight the coronavirus, according to the EPA. The agency announced a move Wednesday that allows products with antimicrobial copper alloys to be marketed with that virus-killing claim — the first product to be registered with such residual properties for nationwide use. (Morton, 2/10)
In related science and research news —
COVID Associated With More Hospitalizations, ICU Care, Mortality Than Flu
Hospitalized adults with COVID-19 are 3.5 times more likely to die than adults with the flu, reports a study today in CMAJ. The study also found that those with COVID were 1.5 times more likely to be admitted to the intensive care unit (ICU) and have 1.5 times longer hospital stays. The researchers collected data from seven hospitals in Toronto and Mississauga in Canada and found that, from November 2019 through June 2020, 763 patients were admitted 783 times with the flu and 972 patients were admitted 1,027 times with COVID-19—the latter making up 23.5% of all hospitalizations during the study's duration. (2/10)
COVID Deaths 3 Times Higher In Nursing Homes With More Non-White Residents
Residents of US nursing homes with more than 40% non-white residents died of COVID-19 at 3.3 times the rate of those of those with higher proportions of white residents, a study today in JAMA Network Open shows. Using the Nursing Home COVID-19 Public File from the Centers for Medicare & Medicaid Services, University of Chicago researchers found that nursing homes with the lowest shares of white residents reported a mean of 5.6 deaths, compared with 1.7 in those with the highest proportions, as of Sep 13, 2020. (Van Beusekom, 2/10)