Haff disease: A One Health review of outbreaks, environmental drivers, and global trends

Background: Haff disease is a rare syndrome of rhabdomyolysis that develops within 24 h of consuming cooked freshwater or marine fish or crustaceans. Despite nearly a century of recognition since its first description in 1924, the causative toxin remains unidentified. Growing evidence suggests a heat-stable, bioaccumulated toxin linked to environmental pollution and ecological change. The disease represents an emerging One Health challenge at the intersection of environmental health, food safety and human health. Methods: A narrative review was conducted, synthesising published reports and outbreak investigations from the USA, China and Brazil – the countries with the highest number of documented cases. Data were compared regarding implicated species, outbreak size, geographic distribution and clinical outcomes. Results: Outbreaks consistently occurred in clusters associated with shared seafood meals. In the USA, buffalo fish (Ictiobus cyprinellus) was most frequently implicated; in China, crayfish (Procambarus clarkii) and in Brazil, a range of Amazonian freshwater species. A dose–response relationship between portion size and disease severity was observed in several outbreaks. Clinically, patients were presented with acute myalgia, myoglobinuria and markedly elevated serum creatine kinase levels. Complications such as acute kidney injury and multiorgan failure were reported. Since the early 2000s, the global increase in case frequency parallels environmental degradation, rising water temperatures and intensified seafood trade. Conclusion: Haff disease illustrates the interdependence of human, environmental and food-system health. Strengthened environmental surveillance, standardised diagnostic criteria and cross-sectoral collaboration are essential to identify causative agents, prevent outbreaks and protect at-risk communities.