The Los Angeles County Department of Public Health said the largest outbreak occurred at the Farmer John meatpacking plant in Vernon, California, which is owned by Smithfield Foods and produces Dodger Dogs, among other products.
Health officials said 153 employees of 1,837 who work at that facility tested positive for COVID-19 when testing was conducted between March through May, and of those 153 employees, 41 returned to work.
The other Vernon facilities with reported outbreaks include Cal Farms Meat Company, CLW (meat), F. Gavina & Sons Inc. (coffee), Golden West Trading (meat and other products), Overhill Farms (frozen food), Rose & Shore (deli meat and prepared foods), Takaokaya USA (tea, seaweed and other products) and Vie De France Yamazaki (baked goods).
Smithfield Foods, which owns Farmer John, is the largest pork supplier in the United States and employs 40,000 people across the country.
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The company said it offers free COVID-19 testing to all of its employees, according to its website, where it also lists a series of measures it has taken to help contain the spread of COVID-19 at its facilities. These measures, according to the company, include increased social distancing, plexiglass barriers and temperature scanning.
COVID-19 has dramatically impacted the food industry in the United States. Dozens of food processing plants across the country have had to shut down for days or even weeks to slow or stop the spread of the virus since March.
Nearly 5,000 meat-packing workers at 115 facilities in 19 states have been infected with COVID-19, according to the Centers for Disease Control.
"We have seen disruption across the entire food supply chain, and of course, the meat supply chain is a subset of that," said Nick Vyas, the executive director of Center for Global Supply Chain Management at University of Southern California, told "Good Morning America." "The disruption started in a meat supply chain, as was the food supply chain as a whole, partly because this assembly line processing lines and the facility itself did not really have the proper method in place to really protect the frontline workers, and we started to see one plant after the other really got exposed with the COVID-19."
Last week, Tyson Foods confirmed 570 workers at its Wilkesboro, North Carolina, poultry facilities tested positive for the virus, and 257 employees tested positive a its Temperanceville, Virginia, facility.
"At Tyson, our team members come first, and we are focused on ensuring they feel safe and secure when they come to work," Tom Brower, senior vice president of health and safety for Tyson Foods said in a statement. "We are working closely with local health departments and using the latest information and resources to protect our team members, their families and our communities."
Tyson said it, too, has implemented a number of safety measures at its facilities, including symptom screenings for all team members before every shift, providing mandatory protective face masks to all team members, as well as a range of social distancing measures, including physical barriers between workstations and in break rooms.
Another Smithfield-owned plant in Sioux Falls, South Dakota, was shut down for three weeks after hundreds of employees tested positive for the coronavirus.
That Smithfield facility, which the company says is responsible for up to 5% of the U.S.'s total pork production, was reopened this month after Smithfield said it was given "positive confirmation from the Centers for Disease Control and Prevention (CDC) and United States Department of Agriculture (USDA) that the company is in full compliance with all CDC and Occupational Safety and Health Administration (OSHA) guidance."
With food supply disruptions, prices are going up at the grocery store. Overall, the U.S. Bureau of Labor's consumer price index report said grocery bills were up 2.6% in April, the biggest monthly increase in nearly 50 years. For meat, the price of fresh beef increased 11.9% during the week ending May 9, compared to the same period last year, and the price of fresh chicken increased 7.5%, according to Neilson.
"What we're seeing is the high prices, shortages in some commodities and this will continue," Vyas said. "This impact will likely outlast the virus itself."