Anisakiasis: An Emerging but Underestimated Parasitic Zoonosis with One Health Perspectives

Abstract

Anisakiasis, commonly referred to as herring worm disease, is an emerging and often under-recognized food-borne parasitic zoonosis caused by the accidental ingestion of third-stage larvae of anisakid nematodes, predominantly Anisakis simplex sensu lato and Anisakis pegreffii, along with species belonging to the genera Pseudoterranova and Contracaecum. Human infection primarily occurs through the consumption of raw, undercooked, or inadequately processed marine fish and seafood contaminated with infective larvae. Although anisakiasis has a global distribution, its epidemiological burden remains largely underestimated due to misdiagnosis, underreporting, and limited awareness, particularly in regions where culinary practices involving raw or minimally processed seafood are gaining popularity. Clinically, anisakiasis presents with a broad spectrum of manifestations ranging from acute gastrointestinal symptoms, such as abdominal pain, nausea, and vomiting, to chronic granulomatous inflammation and severe hypersensitivity reactions, including urticaria and life-threatening anaphylaxis. The pathogenesis involves both direct tissue invasion by larvae and host immune responses, complicating diagnosis and management. The intricate life cycle of anisakid nematodes, involving marine mammals as definitive hosts, crustaceans as intermediate hosts, and fish as paratenic hosts, underscores the ecological complexity and the interconnectedness of marine ecosystems with human health. Given the increasing globalization of seafood trade and changing dietary habits, anisakiasis represents a growing public health concern. Effective control requires enhanced epidemiological surveillance, implementation of stringent food safety measures, and increased consumer awareness regarding proper seafood handling and preparation. Furthermore, the integration of veterinary, medical, and environmental disciplines within a One Health framework is critical for comprehensive risk assessment, prevention, and control of this neglected zoonotic disease.