With South Dakota's number of COVID-19 cases doubling every four days, Gov. Kristi Noem is still holding off on issuing a stay-at-home order.

Around half of the state's cases so far have come from the Smithfield Foods processing facility in Sioux Falls. The plant, one of the largest in the country, closed on Sunday.

"Let's be perfectly clear: a shelter-in-place order would NOT have prevented Smithfield from happening," Noem tweeted on Wednesday.

Noem, an ally of President Donald Trump, is one of just five governors still refraining from implementing any sort of stay-at-home order.

She has, however, announced a trial for the anti-Malaria drug hydroxychloroquine — an unproven coronavirus treatment frequently touted by Trump and several Fox News hosts.

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South Dakota Gov. Kristi Noem is still holding off on issuing a stay-at-home order amid a COVID-19 outbreak at a meat processing plant and the number of cases statewide doubling every four days.

Noem, an ally of President Donald Trump, is one of just five governors who have yet to implement even a partial order.

In Sioux Falls, the Smithfield Foods processing plant — one of the largest in the country and one of the state's biggest employers — closed on Sunday after nearly 300 of its employees tested positive for the coronavirus.

South Dakota's curve is steepening, but Noem held the line Wednesday in a Twitter thread.

"We trusted South Dakotans to exercise personal responsibility to keep themselves and their loved-ones healthy," Noem tweeted. "They've stepped up to the challenge. But some folks in the national press are improperly conflating that decision with the situation at Smithfield."

"Let's be perfectly clear: a shelter-in-place order would NOT have prevented Smithfield from happening," she continued. "They are a critical infrastructure business. They are part of the nation's food supply chain and contribute to South Dakota's role feeding the country and the world."

—Governor Kristi Noem (@govkristinoem) April 15, 2020

The mayor of Sioux Falls has already called for a stay-at-home order after urging the governor to issue one statewide.

However, in addition to her tweets on Wednesday, Noem has previously called the measure something that would "just make people feel good."

Noem insists that her state is going "on offense" by running a trial for the anti-malaria drug hydroxychloroquine, an unproven coronavirus treatment frequently touted by President Trump and several hosts on Fox News.

Noem will hold a town hall on the coronavirus Wednesday night at 7 p.m.