Threat of 'flesh-eating bacteria' spreads along Europe's beaches with climate change

Now that summer has officially begun, millions of tourists are eagerly waiting for their holidays and, in many cases, planning to head to the coast to enjoy the beach. However, this year a long shadow hangs over the tourism sector because of the spread of bacteria in the sea, which has already forced the closure of several beaches in Spain.In recent years, across different parts of Europe’s coastline, episodes of pollution and health alerts have been recorded that have led to restricted access to the sea, against a backdrop of ever-higher water temperatures and growing tourist pressure.“The Mediterranean is showing us what a hotter world represents,” says Union for the Mediterranean Projects, Climate Action and Energy Resilience analyst Hatim Aznague in comments to Euronews. “The countries that share this sea can still choose to share a solution.”The threat of the “flesh-eating” bacteriumParticular concern surrounds the Vibrio bacterium, popularly known as the “flesh-eating” bacterium, a waterborne microorganism that lives naturally in marine and brackish waters, especially in areas where rivers meet the sea. According to the European Food Safety Authority (EFSA) (source in Spanish), “Vibrio is an aquatic bacterium that can be found in seafood”, and some strains can cause anything from gastroenteritis to severe and even fatal infections.Among the most significant species in Europe are Vibrio vulnificus, Vibrio parahaemolyticus and certain variants of Vibrio cholerae. EFSA warns that these bacteria can cause infections through the consumption of raw seafood or contact with open wounds in the water.“Vibrio is a close relative of the bacterium that causes cholera, although the two microorganisms cause very different diseases,” explains (source in Spanish) the organisation Gavi. “In severe cases, the infection can trigger necrotising fasciitis, in which the tissue around the wound breaks down rapidly. The bacterium can also enter the bloodstream, causing sepsis, and in some instances patients require amputation of the affected limb.”In addition, the European Centre for Disease Prevention and Control (ECDC) has warned (source in Spanish) of an “increased risk of Vibrio infections throughout the summer season”, especially during heatwaves, such as the one expected in Europe this June, and in shallow coastal waters. The risk is not only to health but also ecological: these bacteria thrive in environments where the natural balance of the marine ecosystem has been compromised.The Mediterranean, a “preview” of climate changeThis phenomenon is especially visible in the Mediterranean Sea, regarded by scientists as one of the regions most vulnerable to global warming. Aznague, an expert in climate and energy policy, warns that the phenomenon is not isolated but structural. “It is important to stress that the Mediterranean is not a victim of climate change, but a preview of it. It is one of the fastest-warming seas on the planet.”The analyst emphasises that rising water temperatures, combined with pollution and lower salinity in coastal areas, create the perfect conditions for pathogens to proliferate. “Warmer water, especially where it is less salty, at the river mouth and in the lagoons cut off by it, becomes more favourable to pathogenic bacteria.”Recent reports such as EFSA’s warn that “the prevalence of Vibrio in seafood is expected to increase both worldwide and in Europe due to climate change”, especially in low-salinity waters and estuaries. The Mediterranean, with its heavy tourist pressure and rapid warming, is thus becoming a key stage for this biological transformation.An economic impact that hits tourism directlyBeyond the health risk, the spread of Vibrio has direct economic consequences. Aznague himself sums it up bluntly: “On our coasts, the shoreline is not part of the economy, it is the economy!”The closure of beaches or the issuing of health warnings in the height of the season directly affects one of Europe’s most important economic engines: beach tourism. “A closed beach represents a climate impact with an attached bill,” says the analyst, who also warns of the cost of “a reputation that takes years to rebuild.”The Mediterranean is the most visited tourist region in the world, which amplifies the impact of any temporary closure. Hotels, restaurants and local economies depend directly on the stability of the coastline, which is now threatened by increasingly frequent biological phenomena.According to EFSA, rising temperatures and extreme weather events are multiplying the areas at risk, while antimicrobial resistance detected in some strains adds an additional layer of concern for public health.A present risk, not a future oneFor the Union for the Mediterranean (source in Spanish), the problem no longer belongs to a climatic future but to the present. This sea acts as a global thermometer for what could happen in other regions in the coming decades.The solution, Aznague insists, lies in committing to greater cooperation and adopting coordinated action, and he stresses: “It is not acceptable to make concessions on our health or on the climate.”In this context, the Vibrio bacterium is not only a growing health threat but also an indicator of a marine ecosystem undergoing a dizzying transformation. Or, as Aznague sums it up during the interview: “Bacteria are not the story, they are the messengers; the story is a sea thrown off balance by heat and pollution.”