An outbreak of norovirus has affected more than 100 people in the central Portuguese region of Caldas da Rainha, with local health authorities confirming 122 infections as of last week. The outbreak was first detected when the accident and emergency department at the Caldas da Rainha hospital treated over 60 patients presenting with vomiting, diarrhoea, nausea, fever, abdominal pain, and headaches.
According to a statement from the municipal council, laboratory tests conducted by the Instituto Nacional de Saúde Doutor Ricardo Jorge identified the pathogen as Genogroup II norovirus. The majority of cases—approximately 80—are connected to an international youth football tournament organised by the company Footmania, held in the municipalities of Caldas da Rainha and Óbidos between 24 June and 8 July.
Investigation Underway
Public health authorities, together with ASAE (the Food and Economic Safety Authority), have examined the catering service provided by the tournament organiser. Food and surface samples were collected, but no evidence has been found to suggest the outbreak originated from the catering. The investigation remains ongoing to determine the exact source of the infection.
The tournament organiser posted on Facebook, describing a challenging edition: “This year brought us challenges that were not in our plans: an intense heatwave and a viral outbreak that affected participants in our tournament. These were tough days, in which we tried to take decisions quickly and well, always putting everyone’s health before anything else.”
Norovirus is one of the most common causes of gastroenteritis and is highly contagious. It spreads through person-to-person contact, contaminated surfaces, and consumption of contaminated food or water—particularly raw shellfish and poorly washed vegetables. At the start of the summer, health authorities had warned that warmer weather, outdoor meals, and gatherings increase the risk of viral transmission.
This is not the first norovirus outbreak in Europe this year. In May, an outbreak on board the cruise ship Ambition forced the confinement of over 1,700 passengers and crew during a stopover in Bordeaux, France.
Portugal has seen a surge in tourism and international events in recent years, as highlighted by reports such as Where Your Holiday Euro Goes Furthest: Turkey Cheapest Overall, Portugal Best for Hotels. The country's growing popularity as a destination for sports tournaments and festivals—like the NOS Alive Festival—brings economic benefits but also public health challenges, especially when large groups gather.
Local health units continue to monitor the situation, and residents and visitors are advised to practice good hygiene, including frequent handwashing, to prevent further spread. The outbreak serves as a reminder of the importance of robust food safety and sanitation measures at large-scale events across Europe.
