Parasitic infections transmitted through food remain a vastly underappreciated contributor to global disease burden — one that dwarfs public attention relative to bacterial or viral foodborne illness. This WHO-led update reframes the scale of the problem for health systems, public health planners, and anyone evaluating food safety risks in high-burden regions.
Analyzing 22 years of incidence, mortality, and disability-adjusted life-year (DALY) data across 14 invasive parasitic diseases, the study estimates that roughly 277 million illnesses annually are linked to potentially foodborne parasites, with approximately 171 million infections directly attributable to foodborne transmission. The aggregate burden reaches nearly 4.89 million DALYs. Two pathogens dominate the disability toll: Taenia solium — the pork tapeworm responsible for neurocysticercosis — accounts for 1.3 million DALYs, while the liver fluke Clonorchis sinensis contributes 921,000. Both are also the leading parasitic causes of foodborne death. Regionally, the Americas carry the heaviest load, driven primarily by Chagas disease (Trypanosoma cruzi, transmitted partly through contaminated food and drink), while sub-Saharan Africa bears disproportionate burden from T. solium-associated epilepsy. A modest but meaningful global decline was observed from 2000 to 2021, suggesting that interventions — including veterinary controls and antiparasitic treatment campaigns — are having measurable impact.
This update builds on the landmark 2015 WHO Foodborne Disease Burden Epidemiology Reference Group (FERG) report and represents one of the most methodologically rigorous parasitic burden analyses to date, employing hierarchical meta-regression and Monte Carlo uncertainty propagation. The 22-year temporal scope is a genuine strength. Key limitations include heavy reliance on structured expert judgment for foodborne attribution fractions in data-sparse regions, and the inherent challenge of distinguishing foodborne from environmental or vector-borne transmission for pathogens like Trypanosoma cruzi. For health-conscious adults in low-endemic settings, individual risk remains low but travel and dietary exposures to undercooked pork, freshwater fish, and raw produce in endemic regions warrant continued awareness. The broader implication is systemic: parasitic food safety deserves investment on par with bacterial hazards in global health infrastructure.