Emerging foodborne trematodiasis

Abstract

Foodborne trematodiasis is an emerging public health problem, particularly in Southeast Asia and the Western Pacific region. We summarize the complex life cycle of foodborne trematodes and discuss its contextual determinants. Currently, 601.0, 293.8, 91.1, and 79.8 million people are at risk for infection with Clonorchis sinensis, Paragonimus spp., Fasciola spp., and Opisthorchis spp., respectively. The relationship between diseases caused by trematodes and proximity of human habitation to suitable freshwater bodies is examined. Residents living near freshwater bodies have a 2.15-fold higher risk (95% confidence interval 1.38-3.36) for infections than persons living farther from the water. Exponential growth of aquaculture may be the most important risk factor for the emergence of foodborne trematodiasis. This is supported by reviewing aquaculture development in countries endemic for foodborne trematodiasis over the past 10-50 years. Future and sustainable control of foodborne trematodiasis is discussed.

Figure 1

Contextual determinants of foodborne trematodiasis. Solid arrows, negative impact; dashed arrows, positive impact.

Figure 2

Development of freshwater fish production in China, 1952–2002.

Figure 3

Development of freshwater fish production in Opisthorchis viverrini–endemic countries, 1962–2002.

Figure 4

Metaanalysis of studies comparing the prevalence of foodborne trematode infections in villages close to water bodies with distant villages. Values on the x-axis are relative risks. Horizontal bars show 95% confidence intervals. The solid vertical line represents the mean of the combined measure. The diamond represents the combined measure.