Many of the largest outbreaks of SARS-CoV-2 in the USA so far have been in certain kinds of workplaces, including nursing homes and prisons, both of which make sense. But there are also many outbreaks in *meatpacking* plants. Why this occupational venue? Let’s talk about this. 1/
In a list of outbreaks via @nytimes ( https://www.nytimes.com/interactive/2020/us/coronavirus-us-cases.html), other than nursing homes and prisons (and two ships), meatpacking plants are most frequent locus of outbreaks (7 out of top 30 outbreaks). The largest outbreak outside of a prison is in a *meatpacking* plant. Why? 2/
But this contributes to spread of the epidemic! A better approach would be to pay workers more on a daily basis (so that they like their jobs more & so that the plant can recruit more workers) while also increasing & liberalizing sick leave, so more (sick) workers stay home. 5/
Of course, careful attention to working conditions in meatpacking plants also is crucial. 6/
The president declared that meatpacking plants were part of the nation’s “critical infrastructure” given that “closure of any of these plants could disrupt our food supply and detrimentally impact our hard-working farmers and ranchers.” 9/
No mention was made of detrimental impact on hardworking *meatpackers* facing the COVID outbreaks, however. And why meatpacking factories would be ordered open but not PPE factories (to help hospital personnel and patients) is also a bit odd to this public health professor. 10/
But why might meatpacking factories have COVID19 outbreaks in particular, compared to other industrial settings? 11/
Here are two videos available online (in exceptionally sanitary conditions, but you can see the kind of work involved) that show the work situation: and (beginning at 4’20”): 13/
Does meatpacking involve the creation of aerosols and has this possibly caused occupational respiratory outbreaks before? Yes, it has. For instance in this classic 1962 study: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1914989/pdf/pubhealthreporig00091-0054.pdf 14/
In the 2003 SARS-1 outbreak, several super-spreading events were associated with the aerosolization of contaminated body fluids, including possibly vomit at the Metropole Hotel and diarrhea at the Amoy Gardens Estates ( https://www.ncbi.nlm.nih.gov/pubmed/16696450 ), both in Hong Kong. 16/
So that is my theory: meatpacking industry involves a combination of close worker proximity and the intrinsic production of mist and aerosols (eg, through the use of saws) such that any infected worker who coughs will have his expectorated virus wafted to others in the plant. 18/
Of course, meatpacking plants have been notoriously bad places to work, powerfully shown by Upton Sinclair, in his novel, The Jungle, describing the lives if immigrants toiling in the Chicago meatpacking industry in the early 20th century: https://www.amazon.com/Jungle-Upton-Sinclair/dp/1503331865/ 22/
In addition to worker proximity, intrinsic production of mist & aerosols (eg, through use of saws), & policies discouraging sick leave, meatpacking is in a chilled environment. All may facilitate spread of SARS-CoV-2. Many occupational situational factors are surely involved. 24/
For more details on how the meatpacking industry works and the (albeit unclear how distinctive) difficulties in coping with COVID19, see this long and informative thread, via @rudman_ben: https://twitter.com/rudman_ben/status/1256698322493911041?s=21 26/ https://twitter.com/rudman_ben/status/1256698322493911041
Report re meatpacking COVID19 outbreaks via @CDCgov is just out https://www.cdc.gov/mmwr/volumes/69/wr/mm6918e3.htm?s_cid=mm6918e3_x In 115 facilities in 19 states w ~130,000 workers, there were 4,913 cases (3%) & 20 deaths (CFR=0.4%, so far). Report highlights worker proximity & crowded living/transportation. 27/
Analysis of "6-feet rule” in turbulent air conditions (which is relevant to meatpacking and other outbreaks):
based upon extensive simulations of coughing & airborne droplet transmission, saliva droplets can travel 18 feet in light wind. https://aip.scitation.org/doi/pdf/10.1063/5.0011960?download=true& via @EricTopol 31/
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