Nearly 300 workers at a northwestern Missouri pork processing plant have tested positive for the coronavirus, state health officials said Friday.

O'FALLON — Nearly 300 workers at a northwestern Missouri pork processing plant have tested positive for the coronavirus, state health officials said Friday.

The Triumph Foods plat in St. Joseph is the latest of several meat plants around the country to see huge spikes in confirmed cases of the virus.

Missouri's health department oversaw testing this week of more than 2,300 asymptomatic workers at the plant. Dr. Randall Williams, director of the department, said in an interview that results for the first 1,625 asymptomatic workers showed that 259 tested positive for COVID-19, the illness caused by the coronavirus. Thirty-six others previously tested positive.

Results are still pending for 709 workers.

The infected workers are being told to self-isolate, and efforts are underway to determine who they've had contact with. But Williams is not recommending closure of the plant.

"We think the work they do is incredibly valuable, and these are asymptomatic employees," Williams said. "So we feel like by working with our normal public health epidemiological case tracing, we can isolate and quarantine these patients."

Meat plants often employ hundreds of people working next to each other, which can help facilitate the virus' spread.

But Williams said it's uncertain where the St. Joseph workers contracted the virus.

"It's very reasonable they may have gotten it not from work but from where they live, who they live with," Williams said.

President Donald Trump issued an executive order this week requiring meatpacking plants to stay open amid the coronavirus crisis after more than 20 plants suspended operations under pressure from local authorities and their own workers. 

Gov. Mike Parson's stay-at-home order ends Sunday, and businesses can reopen with some restrictions starting Monday. Members of the St. Joseph City Council met Thursday night and decided to allow the city to reopen despite the Triumph Foods outbreak, city spokeswoman Mary Robertson said.

The risk of outbreaks at places like prisons, nursing homes and meat plants prompted Missouri to begin what Williams calls a "boxed-in" approach to testing. Under the plan, when a potential hot spot is determined, the state tests everyone.

Williams said Missouri now has the ability to perform more than 50,000 tests per week, thanks to a strong focus on expanding testing that includes partnering with private companies.

"Other states haven't done that, but we have," Williams said. "We have greatly built up a very purposeful capacity to test."