Anna Camp has revealed she had COVID-19 — and is still suffering from symptoms a month later.

On Tuesday, the “Pitch Perfect” star opened up about her battle with the coronavirus, and explained that she believes she caught the respiratory illness after she went outside without a mask “one time.”

“Hi friends… I felt it was my responsibility to share that I ended up getting Covid-19,” Camp wrote alongside an Instagram photo of her wearing a mask. “I have since tested negative, but I was extremely sick for over three weeks and still have lingering symptoms. I was incredibly safe. I wore a mask. I used hand sanitizer.”

“One time, when the world was starting to open up, I decided to forgo wearing my mask in public,” she continued. “One. Time. And I ended up getting it. I believe it may have been because of that one time.”

The actress explained that for her the coronavirus was “absolutely not” like the flu and detailed the symptoms she’s still experiencing despite testing negative, including “only smelling about 30 percent” of what she used to.

“People are saying it’s like having the flu, but I’ve had the flu, and this is absolutely not that,” Camp said. “The panic of contracting a virus that is basically untreatable and is so new that no one knows the long term irreparable damage it does to your immune system is unbelievably stressful. Completely losing my sense of smell and taste without knowing when or even if they will return is extremely disorienting.”

“I’m only smelling about 30 percent of how I used to now,” she added. “Other persistent symptoms are (a month later) dizziness, extreme fatigue, impacted sinuses, upset stomach, nausea, vomiting, and fever.”

Camp ended her post by urging her followers to wear a mask.

“I’m lucky. Because I didn’t die. But people are. Please wear ur mask,” she concluded. “It can happen any time. And it can happen to anyone. Even that one time you feel safe. We can all make a difference. Wearing a mask is saving lives. Thank you to everyone who reached out to check on me during this scary time.”

“Please be safe out there,” she explained. “Let’s all do our part and wear a mask. I don’t want any of you to go through what I did. Even though it’s a little thing, it can have a huge impact, and it’s so incredibly easy to do❤️”

Camp’s post comes as the coronavirus continues to spread nationwide, with 41 states showing an increase in new cases in the past two weeks, according to the New York Times.

As of July 22, COVID-19 has infected over 3.9 million Americans, with 140,000 reported deaths.