Wilson, who is fully vaccinated, tested positive while competing at the International Swim League (ISL) in Europe.

The 27-year-old, who won gold as a member of Australia’s victorious 4x100m freestyle relay team at the Tokyo Olympics, is under observation at an Italian hospital.

“Even though I am double vaccinated and took the right precaution set in place through the ISL, I have managed to fall to this virus,” Wilson posted on Instagram.

“It’s been a crazy few months and I believe being run down physically and mentally may have made me more susceptible.

“I feel extremely unlucky but I do believe this is a huge wake up call.

“COVID is a serious thing and when it comes it hits very hard. I’d be stupid not to say I wasn’t scared.”

The 27-year-old said she was feeling fine but was hospitalised as a precaution while being isolated from her Los Angeles Current ISL team.

“I’m so lucky for all my family, friends and support people. I can’t believe how much love I have been shown and I’m forever in debt to these people,” she wrote.

“Special thanks to my incredible LA family, you haven’t and won’t ever see a team with a bigger heart than theirs, away from the pool the most incredible compassionate group of people and in the pool we are fighting with every bit of strength.

“I can promise we will be ready to fire come semifinals!

“I’m taking some time to rest and I’m sure I’ll be ready to bounce back in no time.”

The ISL regular season is scheduled to finish on September 29 ahead of finals in November.