The 51-year-old actress tweeted the news on Monday and revealed she was being treated at Virtua Memorial Hospital in Mount Holly.
"Prayers for me please. Yesterday I took an ambulance ride to the hospital," she wrote on Twitter. "I’m still here with pneumonia, I’m on oxygen etc, all covid related of course. I’m in good spirits and in great hands."
Swanson, who has publicly criticized the COVID-19 vaccine and is an avid supporter of former President Donald Trump, told her followers that she is "okay" and is being treated with Baricitinib and blood thinners.
"It behaves exactly like the flu," she tweeted alongside an article about COVID-19 in September.
As word of her diagnosis spread, the New York Post tweeted an article with a headline referencing her as an "anti-vax" actor.
Swanson responded that she is not "anti-vax."
Meanwhile, Twitter users denied her well-wishes, with one user writing, "our prayers are reserved for those who were vaccinated but ended up in the hospital through no fault of their own."
"If only there was a free vaccine you could have taken to greatly minimize those symptoms and not be more of a burden to the exhausted HCWs," another user wrote.
Other followers wished her the opposite, including her former "Pretty in Pink" co-star Jon Cryer.
"OMG I’m so sorry to hear this but glad to hear you are in great hands and getting good care," he tweeted.
"You and your family are in my thoughts. I wish you strength and rest and happiness and health."
Swanson has not confirmed her COVID-19 vaccination status.
She was released from the hospital on Thursday, seemingly in good health.
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