Norovirus Forces Suspension of Shellfish Harvesting in Thau Lagoon Ahead of New Year

The prefecture of Hérault has announced a temporary halt on harvesting and selling oysters, mussels, and clams from the Thau lagoon due to confirmed norovirus contamination in the water. This measure comes after cases of foodborne illness associated with consuming these shellfish and just before the New Year's celebrations, dealing a blow to the local shellfish industry.

The contamination likely stems from exceptional heavy rains and flooding in mid-December, with the Hérault River reaching levels unseen since 1997 at 3.68 meters. The prefecture clarified that shellfish harvested before December 19, 2025, or from other unaffected production zones remain exempt from this ban.

Covering approximately 7,000 hectares near Sète and Agde, the Thau lagoon is a critical ecosystem and the largest shellfish farming area in the Mediterranean, contributing to around 10% of France's oyster production and supporting some 3,000 jobs.

Authorities have emphasized that this suspension is temporary and will be lifted once health safety standards are restored, allowing production zones to reopen. The crisis highlights the vulnerability of coastal aquaculture to environmental factors such as flooding and contamination.

According to the prefecture, “this decision reflects a necessary precaution to ensure consumer safety,” and reopening depends on meeting required sanitary conditions.