Paris Olympics: Two Portuguese triathlon athletes fall ill after swimming in the Seine river

Vasco Vilaça and Melanie Santos developed gastrointestinal infections after swimming in the Seine River on 5 August during their triathlon competition at the Paris 2024 Olympic Games.

Vilaça's symptoms are stronger than his female counterpart, according to the Portuguese Olympic Committee (COP).

"His clinical condition is stable and the COP health team is taking all measures to monitor and provide conservative treatment for the athlete in the Olympic Village," stated the COP's statement published on 7 August.

The COP added: "Over the last few days, athlete Melanie Santos has also developed similar symptoms, but in a less acute form".

Belgium did not participate in the triathlon mixed relay in Paris on Monday after athlete Claire Michel became sick and withdrew from the competition.

Along with Michel, another three triathletes — of the more than 100 who competed in the men’s and women’s races on 31 July — became sick in the following days, though it is unclear whether the water was to blame.

With a few exceptions, swimming in the Seine has been prohibited since 1923 because the water has been too toxic.

Paris undertook an ambitious plan, including €1.4 billion in infrastructure improvements to ensure that some swimming events could be held in the river.

The investment included the construction of a giant basin to capture excess rainwater and keep wastewater from flowing into the river, renovating sewer infrastructure and upgrading wastewater treatment plants.