Salmonella Suspected in Ourthe River: Eight Hospitalized

At least eight young people on a summer camp in the Belgian Ardennes are suspected to have contracted salmonella after swimming in the Ourthe river on Thursday, according to Het Laatste Nieuws. The group of approximately 30 campers was staying at the Domaine de Palogne in Vieuxville, near Ferrières in Wallonia, when several participants began experiencing vomiting and diarrhea after a swim in the river.

Emergency Response and Hospitalization

The affected young people were transported to hospital, with four ambulances and police teams mobilized to respond to the incident. According to RTL Info, all hospitalized campers had been released by Friday late morning. The camp leadership decided to stop the camp, and some parents arrived to pick up the remaining children.

Official Warning: Do Not Enter the River

Christian Verdin, the mayor of Ferrières, issued a stark warning to the public. “Don’t go into the river, a single contact with the water can poison you,” Verdin said. “What happened to the young people is a warning that reminds us of the risks of swimming at this time. We must be careful.”

The municipality strongly advises against swimming in the Ourthe, citing the very low water levels caused by ongoing drought conditions that concentrate bacteria and increase health risks. The Domaine de Palogne’s kayak rental page confirms that kayaking operations are currently closed, noting that during prolonged dry periods, low water levels force the suspension of the activity.

A Recurring Problem During Heat Waves

This is not the first time the Ourthe has been linked to waterborne illness during hot, dry summers. In July 2017, three scout camps along the river showed signs of intoxication, with some participants requiring hospitalization, as RTBF reported. Investigators at the time considered several possible causes, including dishes washed in cold river water, food washed in the river, and drinking water stored in warm containers.

In August 2020, cyanobacteria—commonly known as blue-green algae—were detected in the Ourthe at Esneux, prompting four communes (Esneux, Ferrières, Hamoir, and Comblain-au-Pont) to jointly ban swimming in the river, according to RTBF. The coordinated ban followed the death of a dog that had drunk water from the river. As L’Avenir reported, high temperatures and low water levels favored the bacterial development.

Water Quality and the Ourthe

The Ourthe is a popular recreational river in the Belgian Ardennes, flowing through the province of Liège in Wallonia. It draws thousands of visitors each summer for swimming, kayaking, and camping along its banks. While swimming is not formally prohibited in most waterways, the Contrat de Rivière Ourthe—the organization that manages the river basin—strongly advises using official swimming zones where water quality is measured weekly during the summer at Chérapont, Maboge, Hotton, and Noiseux.

The organization warns that river water can be contaminated by micro-organisms or pollutants, and that degraded water quality can lead to health issues through skin contact or accidental ingestion. It also notes that swimming is expressly prohibited within 50 meters upstream and downstream of dams due to dangerous currents and eddies.

The current incident comes as Belgium experiences its third heat wave of 2026, with temperatures reaching record levels. On August 14, Belgium officially confirmed the heat wave with 30.4°C recorded at Uccle. The drought has led to very low water levels in rivers across the country, concentrating bacteria and other pathogens and making natural waterways significantly riskier than usual.

Salmonella: A Known Waterborne Threat

Salmonella is a genus of bacteria that causes salmonellosis, an infection characterized by diarrhea, fever, and abdominal cramps. Symptoms typically appear within 8 to 72 hours after exposure. In rivers, salmonella can be present due to agricultural runoff, sewage, or animal waste—and low water levels combined with high temperatures create ideal conditions for the bacteria to proliferate.

This pattern was noted by authorities during the 2020 cyanobacteria incident, when Bruno Salamon, chief of post at the Esneux police station, explained that the bacterium is “presumably present there all year round, but in periods of heat as at the moment with very low waters, it proliferates and that’s when it becomes dangerous.”

What to Watch For

Authorities are awaiting the results of water quality tests to confirm the presence of salmonella and determine the source of contamination. Questions remain about whether a formal swimming ban will be implemented across multiple communes, as was done in 2020, and whether this incident will lead to changes in how swimming in the Ourthe is regulated.

The Contrat de Rivière Ourthe has been recruiting volunteer “river stewards” to inform tourists about water quality and safe practices along the river—an initiative that may gain renewed urgency in light of this incident. The organization also publishes regular updates on swimming conditions and water quality measurements at its monitoring points.

For now, the message from local officials is clear: stay out of the river. As the mayor of Ferrières warned, even a single contact with the water could be enough to cause serious illness. With the heat wave expected to persist and water levels remaining critically low, the risks are unlikely to diminish in the coming days. Residents and visitors alike are urged to heed the warnings and seek out official swimming zones where water quality is regularly monitored.