SAVANNAH, Ga. — Four employees of a major poultry producer’s operations in rural southwest Georgia have died after becoming infected with the coronavirus, a company spokesman said Friday.

Tyson Foods spokesman Gary Mickelson said three of the employees worked at the company’s chicken processing plant in Camilla, while the fourth person worked in a supporting job outside the plant. He declined to say how many workers there have tested positive for COVID-19, the disease caused by the new virus.

American workers who process the nation’s meat have proven especially susceptible to the new virus, as they work shoulder-to-shoulder on production lines. Several US plants have closed because of outbreaks, including a large plant owned by Smithfield Foods in Sioux Falls, South Dakota, that produced roughly 5% of US pork before it was shut down after more than 500 workers became infected.

Mickelson said two other Tyson Foods workers have died from the virus at its plant in Columbus Junction, Iowa.

“We realize everyone is anxious during this challenging time and believe information is the best tool for combating the virus,” Hector Gonzalez, Tyson’s senior vice president for human resources, said in a statement. “That’s why we’re encouraging our team members to share their concerns with us, so we can help address them.”

The Tyson Foods pork processing plant in Columbus Junction, IowaAP

Gonzalez said the company has improved safety measures at the Camilla plant by checking employees’ temperatures, requiring workers to wear face coverings, installing dividers at work stations and providing more space in break rooms. He said the company in March had “relaxed our attendance policy to encourage workers to stay at home when they’re sick.”

The Retail, Wholesale and Department Store Union, which represents 2,000 workers at the Georgia chicken plant, identified the three plant employees who died as women who had worked there for 13 to 35 years. A statement from the union said many plant employees are “sick or in quarantine.”

“It’s too little too late here,” Edgar Fields, president of the union’s Southeast Council, said in a statement Friday.

The Georgia Department of Public Health reported Friday that at least 668 deaths statewide have been linked to the virus. Infections have been confirmed in more than 17,400 people. About 20% of them were hospitalized.

In Georgia’s rural southwest corner, where the Camilla plant is located, the rate of coronavirus infections and deaths have outpaced far more densely populated regions of the state. The union said many plant employees live in neighboring Dougherty County, which leads Georgia with 91 coronavirus deaths.

For most people, the new coronavirus causes mild or moderate symptoms that usually clear up within weeks. For some, it can cause severe illness and be life-threatening.

The union has called on poultry processors to require employees to quarantine themselves for 14 days, and pay them sick leave, when they’re exposed to co-workers testing positive for the virus. It also wants individual departments to be shut down for 72 hours and cleaned after a worker tests positive.