This is the objective: to no longer relive this winter of 2023-2024 where the sale of oysters from the Arcachon basin was banned from December 26, 2023 to January 19, 2024, causing a hole in turnover and in consumer confidence .
Oyster farmers have still not recovered from this norovirus crisis, this bacteria causing gastroenteritis which is found in wastewater and which was observed in the waters of the Basin after all the networks overflowed during the incessant rains of autumn 2023. Pollution for which they are in no way responsible, but which they still pay for in their treasury, without the slightest compensation being granted to them.
Last October, after the elected representatives of the Basin announced tens of millions of euros of investment in the networks, Olivier Laban, president of the regional shellfish committee Arcachon-Aquitaine (CRC), explained that oyster farming should not just wait for the promises of elected officials: “Marc Druard, the former president of the CRC, said that solutions always came from the profession itself. So we take the subject head on. We have no choice. »
Currently, norovirus is only reported after the fact, when a certain number of collective foodborne illnesses linked to the consumption of oysters are traced by the Regional Health Agency, leading to a ban on the sale. Oyster farmers want to take things upstream.
Monitoring in place
The CRC is therefore setting up monitoring of nororovirus in oysters from the Basin entrusted to its oyster health defense group. Thus, “during the winter risk period, when the water tables are high, the network is under tension and we are possibly experiencing epidemics of gastroenteritis, we will monitor once a week at seven points in the Basin for the presence of norovirus and of bacteriophages in order to assess the health status of our products”. After a call for tenders, the CRC chose the Actalia laboratory for “biological analysis services on oyster samples”, the same as that chosen by Veolia for analyzes at the outlet of its wastewater treatment plants.
The “test” oysters are in the parks. 22 weeks of monitoring are planned by the CRC between mid-November and mid-April, the period at risk of epidemics and network overflows in the event of very heavy rain. If the presence of norovirus is detected, before the alert thresholds are exceeded, oyster farmers will be able to bring in their oysters to purify them, and then sell them without risk.
A diagnosis of purifying pools
The CRC will carry out a diagnosis of the equipment of oyster farming establishments in the Arcachon basin with purifying basins. Not everyone has one. And to equip those who are not, the CRC will apply for grants from the European Fund for Maritime Affairs, Fisheries and Aquaculture. It will also be necessary to find solutions to create these basins in areas under real estate pressure such as Cap Ferret.
