World champion Boglárka Kapás is among nine of the Hungarian national swimming team to test positive for coronavirus.
The 26-year-old, the 200 metre butterfly gold medallist at the 2019 World Championships in Gwangju, revealed she had coronavirus on social media.
Kapás also earned a bronze medal at the Rio 2016 Olympics in the 800m freestyle.
"I have tested positive for COVID-19," she said.
"I don't have any symptoms yet and that's why it's important for you to know that even if you feel healthy you can spread the virus.
"Please be careful, stay at home and stay healthy."
Eight other members of the Hungarian national team – seven swimmers and one coach – have also tested positive for coronavirus.
Although some of the swimmers have chosen not to share their diagnosis publicly, world and European bronze medallist Dominik Kozma, world bronze medallist Richárd Bohus and European silver medallist Dávid Horváth have revealed they are among the group.
Many of them recently participated at a training camp in Erzurum in Turkey.
Hungarian Swimming Federation President Sándor Wladár confirmed the members of the team would now be in self-isolation for two weeks and would be monitored for signs of symptoms.
There have now been more than 875,000 confirmed cases of coronavirus worldwide, with just under 45,000 deaths.
In Hungary, 525 people have been infected with 20 losing their lives.