![]() ![]() These larvae can survive for weeks off a host provided there is enough humidity. Once outside the host, the larvae called miracidia hatch out of the eggs in 7 to 15 days. A single liver fluke can produce up to 25'000 eggs a day! They are passively transported downwards and expelled with the feces. These eggs reach the gall bladder and are passed to the host's gut when the gall bladder is emptied. Life cycle and biology of Fasciola hepaticaįasciola hepatica has an indirect life cycle with amphibious snails as intermediate hosts, typically from the genus Lymnaea.Īdult flukes produce eggs in the biliary ducts of their hosts. with a cap-like cover) and of a yellowish to greenish color derived from the host's bile. The eggs of liver flukes are about 80x140 micrometers, with an oval form, operculated (i.e. they have both male and female reproductive organs. Liver flukes are simultaneous hermaphrodites, i.e. without exit: the only opening is the mouth) and not linear, as in most animals, but branched, ending in several blind ducts (called coeca). Liver flukes have no external signs of segmentation. The mouth ends in the pharynx, a muscular tube that allows sucking. The body surface is covered with numerous spines. Liver flukes have two suckers, both in the ventral side. The have a pink-grayish to dark red color. Anatomy of Fasciola hepaticaĪdult liver flukes have a flat body, an oval shape, and are rather large: up to 30 mm long and 15 mm wide. Predilection sites of Fasciola hepatica are the biliary ducts in the liver and the gall bladder. You can find additional information in this site on the general biology of parasitic worms and/or flukes. Normally humans become infected through ingestion of water contaminated with infective cercariae (see below under life cycle), not by ingesting adult flukes or their eggs. The same applies to pets infected with liver flukes. BUT experimental studies suggest that humans may be infected when consuming raw livers contaminated with juvenile liver flukes. ![]() If livestock is infected with liver flukes, it is not directly contagious for humans, neither through contact, nor when consuming meat, milk or blood of contaminated animals, nor through the feces. Are animals infected with Fasciola hepatica contagious for humans? The disease caused by liver flukes is called fasciolosis, fasciolasis, distomatosis or liver rot. Horses, dogs and cats can be occasionally infected, especially in rural environments, but liver fluke is usually not an issue for these animals. Pigs kept outdoors can also be affected, but liver flukes are usually not a problem in housed pigs. ![]()
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