Actress Anna Camp has revealed that she contracted Covid-19 after not wearing a mask in public just once.

In an Instagram post, the actor opened up about how she contracted the virus when she stepped out without a mask "one time", after public places began reopening, reports variety.com.

"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. One. Time. And I ended up getting it," she wrote.

She continued: "I've had the flu, and this is absolutely not that. 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."

Camp further shared that after feeling "extremely sick for over three weeks", her sense of smell is only back up to 30 per cent.

She has tested negative for coronavirus subsequently, but still has lingering symptoms such as "dizziness, extreme fatigue, impacted sinuses, upset stomach, nausea, vomiting and fever".

"Wearing a mask is saving lives. Thank you to everyone who reached out to check on me during this scary time," said Camp, adding: "Please be safe out there. 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."