Fascioliasis: Systematic Review

Fascioliasis is among important parasitic diseases which limit productivity of ruminants in particular cattle. Fasciola hepatica and Fasciola gigantica are the two liver flukes commonly reported to cause fascioliasis in ruminants. Fasciola hepatica may be acquired by man, but not directly from cattle. A person must ingest the metacercaria in order to become infected. The geographical distribution of trematodes species is depending on the distribution of suitable species of snails. The genus Lymnea in general and Lymnea truncatula in particular are the most common intermediate host for Fasciola hepatica. The interaction between moisture and temperature determines the survival and reproduction rate of the snails and the parasites. To support a diagnosis, account should be taken of grazing history and seasonality of fascioliasis in the locality. There should be fluke eggs in the faeces and characteristics hepatic lesions at necropsy. Serological tests such as the enzyme linked immune sorbent assay (ELISA) have shown promise, particularly for diagnosis of infections in cattle. In addition to rendering the liver unsuitable for human consumption, it causes loss through death, reduction in meat and milk inhibited reproduction, morbidity impaired growth reduction in carcass weight, reduction in wool growth and quality, decreased feed intake, conversion and lowered resistance. Reduction of pasture contamination with metacercariea will reduce future risk. This can be done by preventing the snails from becoming infected with F.hepatica or by diminishing the size of the snails’ population. Strategic anthelmintic treatment with appropriate fluckicide and a combination of control measure includes drainage; fencing and molluscicde should be used to control and prevent the disease.