Reduced meat output from the shutdowns threatens to tighten supplies of certain products at a time when demand is rising at grocery stores as the country battles COVID-19, the respiratory illness caused by the novel coronavirus.

Tyson Foods Inc shut a hog slaughterhouse in Columbus Junction, Iowa, for the week after more than 24 cases of COVID-19 involving employees at the facility, according to a statement. The company said it would divert hogs to other pork plants in an attempt to minimise the disruption from the closure.

The facility kills about 10,100 pigs a day, or about 2 percent of the country's total slaughtering capacity, said Steve Meyer, economist for US commodity firm Kerns and Associates.

National Beef Packing Co said it suspended cattle slaughtering this week at a plant in Tama, Iowa, for a cleaning that was previously scheduled for later this month.

"These are unprecedented times for our industry," National Beef said in a statement.

JBS USA said in a statement it halted operations at a beef plant in Souderton, Pennsylvania, and would restart production on 16 April. It added it decided to shut the facility to make sure it had "the appropriate management leadership in place before resuming operations."

JBS, a subsidiary of Brazil-based JBS SA, reduced operations at the facility last week after senior managers suffered flu-like symptoms.