Reemergence of cattle paramphistomiasis in France: Current review of epidemiology, pathophysiology and diagnosis

The prevalence of cattle paramphistomiasis is growing in France. This recent reemergence may be related to several factors: limited number of specific anthelmintics available, longevity and high prolificity of adult worms, decreasing prevalence liver fluke which increases the availability of the snails which act as intermediate hosts for paramphistomids, and extensification of cattle farming. Although clinical signs are not very typical, the pathogenicity of paramphistomiasis cannot be ignored, due to the risk of acute form due to immature worms (difficult to identify) and of recurrent bloating due to the mechanical effect of adult worms. However, the pathogenicity of paramphistomids is much milder than that of Fasciola hepatica. There is currently no immunological method available for this diagnosis, a clinical suspicion is confirmed by faecal egg counts (epg), but there is no formal correlation between their numbers and the parasite load.