Food & Climate
An assessment by the European Food Safety Authority (EFSA) anticipated that the occurrence and levels of Vibrio in seafood will rise in response to coastal warming and extreme weather events, like heatwaves.
Vibrios are waterborne bacteria that mainly live in marine coastal waters and brackish areas (where rivers meet the sea) and thrive in warm waters with moderate salinity, according a report seen by “Food & Climate” platform.
Experts assessed 46 studies in 16 countries covering the 2000 to 2022 period. Vibrio parahaemolyticus was found in 20 percent of more than 10,600 tested seafood samples, with one in five positives containing pathogenic strains. Vibrio vulnificus was detected in around 6 percent of almost 3,000 seafood samples. The prevalence of Non-chlorogenic Vibrio cholera was estimated at 4 percent, according to “EFSA”.
In the EU, 32 outbreaks caused by Vibrio in seafood were reported from 2010 to 2021, causing 221 cases, of which 57 were hospitalized. 75 Rapid Alert System for Food and Feed (RASFF) notifications covering Vibrio in seafood were reported between 2010 and January 2023. Only four were associated with food of EU origin.
Studies on Vibrio isolates found in seafood or from isolates causing foodborne infections in Europe detected resistance to several antimicrobials, including those of last resort.
Compulsory reporting
Scientists said a priority for future research is establishing an EU-wide baseline survey for Vibrio in seafood products, including at the primary production and retail stages. They recommended developing a case definition for human vibriosis at the EU level and considering vibriosis for compulsory reporting.
A study was published at “Nature”, titled “Control of Vibrio vulnificus proliferation in the Baltic Sea through eutrophication and algal bloom management”, said, The Baltic Sea is a semi-enclosed marginal sea of the Atlantic located in northern Europe, with a coastline of approximately 8000 km and covering an area of 415,266 km.
Saline inflows through the North Sea produce a 2000 km long lateral surface salinity gradient throughout the entire Baltic Sea, ranging from high salinities (>25) in the transition zone of the Kattegat to low salinities (<5) in the Gulf of Bothnia.
The Baltic Sea is characterized by an estuarine-like circulation due to the positive freshwater budget. The drainage area of the Baltic Sea encompasses a population of approximately 85 million, and is consequently heavily influenced by eutrophication. In addition, annual mean sea-surface temperatures are rising and the ecosystem is expected to be increasingly affected by warming in the coming decades, and will be faced with extended heat wave durations.
Consumer recommendations
These changes favour the growth of pathogenic bacteria of the genus Vibrio and an increase in Vibrio spp. abundances, infection rates, and fatal cases along the Baltic Sea coastline has been reported. The infections of predominantly immunodeficient humans can be associated with the consumption of raw or undercooked shellfish, but in the Baltic Sea, they frequently manifest as skin infections resulting from direct contact with coastal brackish water. Only a low number of infections are currently associated with Vibro vulnificus in the Baltic Sea, but these are usually severe and often lethal.
In 2022, the German Federal Institute for Risk Assessment (BfR) also published a health risk assessment on the occurrence of Vibrio in food, which said that the consumption of raw or insufficiently cooked food products is one of the most critical factors for transmission.
Measures such as high‐pressure processing, irradiation, or depuration reduce the levels of Vibrio in seafood, but maintaining the cold chain is essential to prevent their growth.
Consumer recommendations include proper handling and cooking of seafood and avoiding the consumption of raw or undercooked products, especially for vulnerable individuals.
Australia’s largest Vibrio parahaemolyticus outbreak in raw oysters in 2021 affected more than 250 people and led to Food Standards Australia New Zealand (FSANZ) requesting information from several countries, including those in the EU, about Vibrio in 2022, according to “Food safety news”.