The Kane County Health Department ordered the temporary closure of the meat processing plant, as officials work to find out the number of employees who are sick with the virus.
The daughter of a Smithfield employee who's in the hospital battling the deadly virus spoke with ABC7 Saturday. The family asked to remain anonymous over fears of the worker losing her job at the St. Charles plant.
"She is not well. She is on oxygen," the family member said. "I think overall, she is struggling. She has lost a lot of weight. This is not the flu."
The employee, who's in her 60's, has been sick with COVID-19 for about two weeks. Her family believes she contracted the virus at the facility.
"She ended up in the hospital when she lost consciousness because her O2 levels were so low," the family member said.
The woman's family claims that at least 19 workers have tested positive for the virus at the St. Charles plant alone.
But Smithfield Foods - one of the country's leading protein companies - will not say if they have any COVID-19 positive employees at the plant, citing privacy concerns.
The Kane County Health Department said they are looking into the number of cases linked to the facility.
"They are hiding behind non-disclosure agreements, HIPAA, they are not notifying their employees when they come in contact with other employees who have COVID," the family member said.
The closure at the St. Charles plant comes just days after a worker filed a federal lawsuit against Smithfield Foods, alleging unsafe working conditions at the companies plant in Missouri.
Other Smithfield food plants in the Midwest have closed because of COVID-19, including one in Cudahy, Wisconsin, near Milwaukee. Smithfield said a small number of employees at the Wisconsin plant have tested positive for the virus.
Smithfield also plans to suspend operations at its Monmouth, Illinois facility next week after the company said a "small portion" of employees tested positive for the virus.
The Monmouth plant represents approximately 3% of U.S. fresh pork supplies and also produces bacon, according to Smithfield.
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CEO Ken Sullivan released a video message about the COVID-19 pandemic.
"We are taking the utmost precautions to ensure the health and well-being of our employees and consumers," Sullivan said. "As a food manufacturer, there are thousands of procedures we follow everyday to create a highly sanitary environment to produce our products safely."
Smithfield Foods said they are doing everything in their power to protect their team members from COVID-19 in the workplace, including adopting a series of new processes and protocols that exceed CDC guidance. The company is implementing thermal scanning to identify employees with elevated temperatures and boosting PPE to include masks and shields.
Smithfield said they have continued to run the facilities for one reason - to sustain the nation's food supply during a pandemic.
"We are a food company and besides COVID-19, indeed because of it, we are working around the clock to do what we do best - that is deliver good food responsibly," Sullivan said.
But families said employees' safety needs to come first, saying the company should have closed before the health department was called in.
"They produce meat. I would not consider that an essential service, especially when we are putting people's lives at risk," the family member said.
Smithfield employs 40,000 people nationwide.
The Associated Press contributed to this report.