MIT professors argue that unfounded fear about how COVID-19 spreads has unnecessarily forced the closure of schools, offices buildings, and other indoor venues.
Not all indoor settings are the same: ventilation varies, size varies, occupancy varies. Not only that, the activities people perform indoors also vary a lot. So, the 6-foot social distancing protocol—allocated by boththe Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO)—doesn’t always apply, according to a study in the journal PNAS (Proceedings of the National Academy of Science of the United States of America).
Investigators with the Massachusetts Institute of Technology (MIT)—Martin Z. Bazant, PhD, a professor of chemical engineering and applied mathematics, and John W.M. Bush, PhD, who teaches applied mathematics—have offered what they hope will be a guide for schools, businesses, policymakers, and individuals to better access the risk of contracting COVID-19 indoors. They argue that their data suggest that things like school closings and occupancy limits may not be necessary in many instances.
In an MIT press release, Bazant said that “I’d like to use this work to establish the science of airborne transmission specifically for Covid-19, by just taking into account all factors, the available data, and the distribution of droplets for different kinds of activities.”
Social distancing rules should be pliable: Sometimes you’ll need more, sometimes less will do. “If you understand the science, you can do things differently in your own home and your own business and your own school,” Bazant said in the press release.
In the same press release, Bush offered this example: “My mother is over 90 and lives in an elder care facility. Our model makes it clear that it’s useful to wear a mask and open a window—this is what you have in your control.”
Bush said that his mother felt safe attending an exercise class at the facility because the participants would be 6 feet apart. However, the space of the exercise room and the number of participants would actually make that a high-risk activity.
Their study is being touted by some as evidence that many places that have been shut down don’t need to be. “Oftentimes the space is large enough, the ventilation is good enough, the amount of time people spend together is such that those spaces can be safely operated even at full capacity and the scientific support for reduced capacity in those spaces is really not very good,” Bazant told CNBC. “I think if you run the numbers, even right now for many types of spaces you’d find that there is not a need for occupancy restrictions.”
Bazant and Bush synthesized data from indoor spreading events, and estimated an infectious dose of 10 aerosol-borne virions.
“Case studies are presented for classrooms and nursing homes, and a spreadsheet and online app are provided to facilitate use of our guideline,” the study states. “Implications for contact tracing and quarantining are considered, and appropriate caveats enumerated. Particular consideration is given to respiratory jets, which may substantially elevate risk when face masks are not worn.”
They gathered data using an app and website developed by Kasim Khan in which specific details of what’s going on in an indoor setting are entered—including the variables mentioned above. Then they estimated how long it would take under the various circumstances for the virus to spread from 1 person infected with COVID-19.
They used real-world events, such as the Skagit Valley Chorale in Washington state, where the Skagit Valley Chorale in Washington state, where 86% of the elderly participants became infected by COVID-19 during a 2-hour choir practice.
“Similarly, when 23 of 68 passengers were infected on a 2-hour bus journey in Ningbo, China, their seated locations were uncorrelated with distance to the index case,” the study states. “Airborne transmission was also implicated in the COVID-19 outbreak between residents of a Korean high-rise building whose apartments were linked via air ducts. Studies have also confirmed the presence of infectious SARS-CoV-2 virions in respiratory aerosols suspended in air samples collected at distances as large as 16 ft from infected patients in a hospital room.”
"social" - Google News
April 27, 2021 at 12:20AM
https://ift.tt/3vpiT2i
Importance of Social Distancing Overstated, Study Says - Infection Control Today
"social" - Google News
https://ift.tt/38fmaXp
https://ift.tt/2WhuDnP
Bagikan Berita Ini
0 Response to "Importance of Social Distancing Overstated, Study Says - Infection Control Today"
Post a Comment