Australian chef de mission Anna Meares has confirmed that a member of the water polo team is in isolation in a single room in the Olympic village.
The player, who has not been named, has tested positive to COVID.
Meares told reporters on Tuesday that the athlete belonged to the Stingers water polo team.
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She said other staff members had also displayed some other worrying health signs, but so far the water polo player was the only person to have tested positive to the virus.
The player presented with symptoms late on Monday night.
The AOC is testing close contacts, while team members are wearing masks.
It is expected, however, the player will be able to resume training at some point during the week.
Meares also said Olympic team officials had been briefed on the alleged sexual assault of an Australian woman in Paris.
According to local media, French police are investigating the allegation that the tourist was sexually assaulted by five men.
Meares said she had heard of no threats against team members, but they are being advised to be careful when going outside the athletes’ village.
“I have been informed, it sounds horrific. Obviously our hearts go out to the woman involved and we hope she’s being cared for and supported in the trauma she’s experienced,” Meares said.
“There’s not a lot of detail and information that has come through.”
Meares reiterated that team members had been briefed thoroughly on security and safety precautions.
“What information we’re passing onto our athletes is that security presence is really, really high and that’s in order for them to act as quickly as possible to keep them safe,” she said.
“We don’t yet have any feedback from our athletes that they have felt unsafe – we are encouraging them, if they go out of the village, not to go out on their own, not to wear (their) team uniform, just to wear plain clothes.
“We’re just waiting on further information on the actual case itself.”
The alleged attack happened early on Saturday morning (local time) on Boulevard de Clichy.
The Games opening ceremony is on Friday evening.
– With AAP