A VIRUS has struck down the Australian women’s water polo team with four members placed in quarantine.

The four players will be kept in a separate building in the Olympic Village than the rest of their teammates for at least the next 48 hours.

It’s unclear what the virus is, but the Nine Network reported it was thought the players were infected while they were training in Rome, just before flying to Brazil for the Olympic Games.

Chef de Mission Kitty Chiller said medical staff were keeping watch over them.

“We’ll keep them in isolation, Dr David Hughes will keep a close eye on them,” she told Nine News.

The water polo competition begins on Saturday.

The Australian Stingers won a bronze medal in London in 2012, and are hoping to get another medal in Rio.

The sickness affecting the Stingers players will be sure to make team and Games officials nervous, given the controversy and concern over the state of the water in Rio.

Government and Olympic officials admit efforts to treat sewage and clear garbage from Guanabara Bay and the city’s beaches have been insufficient, prompting warnings from health experts to athletes to “keep their mouths shut”.

The bay will host the sailing and windsurfing events at the Olympics.