What disease does Fasciola cause?
What is fascioliasis? Fascioliasis is an infectious disease caused by Fasciola parasites, which are flat worms referred to as liver flukes. The adult (mature) flukes are found in the bile ducts and liver of infected people and animals, such as sheep and cattle.
Does Fasciola hepatica cause tissue damage?
The Acute Phase (Acute Fascioliasis) Larval migration, especially through the liver, can result in tissue destruction, inflammation, local or systemic toxic/allergic reactions, and internal bleeding.
What are the symptoms of fascioliasis?
Early (acute) symptoms of fascioliasis may include fever, nausea, vomiting, diarrhea, a swollen liver, liver function abnormalities, skin rashes, shortness of breath and abdominal pain or tenderness.
How does Fasciola hepatica cause disease in animals?
It occurs as a result of ingesting moderate numbers (200–500) of metacercariae over much longer periods of time. Clinical signs include anemia, unthriftiness, submandibular edema, and reduced milk production, but even heavily infected cattle may show no clinical signs.
What do flukes do to humans?
The long-lived flukes can cause long-lasting chronic inflammation of the bile ducts, which often leads to further problems. Four to six months after they settle in the bile ducts, the adult flukes start producing eggs, which are then passed out into the intestines.
How is human infection created with Fasciola?
Fascioliasis is infection with the liver fluke Fasciola hepatica, which is acquired by eating contaminated watercress or other water plants. Clinical manifestations include abdominal pain and hepatomegaly.
Can liver fluke affect humans?
Liver flukes are parasites that can infect humans and cause liver and bile duct disease. There are two families of liver flukes that cause disease in humans: Opisthorchiidae (which includes species of Clonorchis and Opisthorchis) and Fasciolidae (which includes species of Fasciola).
How long can a fluke live in human lungs?
Then they pass through the diaphragm, and invade the lungs. There, they develop into adults and produce eggs. Adults can live 20 years if not treated. The flukes may also go to the brain, liver, lymph nodes, skin, or spinal cord where they form cysts and produce eggs.
What parasite attacks the liver?
Fascioliasis is a rare infectious disorder caused by parasites. These parasites are liver flukes that live in plant-eating animals. Liver flukes can be found on water plants in certain parts of the world. When the parasite invades the liver, bile passages may be blocked.
Why is Fasciola hepatica called liver fluke?
caused by the liver fluke Fasciola hepatica, a small parasitic flatworm that lives in the bile ducts and causes a condition known as liver rot. Among domestic animals, the sheep liver fluke (Fasciola hepatica) may cause debilitating and fatal epidemics (liver rot) in sheep.
Why is Fasciola also called liver fluke?
Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic trematode (fluke or flatworm, a type of helminth) of the class Trematoda, phylum Platyhelminthes. It infects the livers of various mammals, including humans, and is transmitted by sheep and cattle to humans the world over.
Can Fasciola Miracidia infect humans?
Humans become infected from ingestion of contaminated aquatic plants, such as watercress, in sheep- and cattle-raising areas. After ingestion, the metacercaria penetrate the intestinal wall, enter the peritoneal cavity, and then penetrate through Glisson capsule into the liver.
Is Fasciola carcinogenic?
hepatica infection and liver fibrosis has been suggested but its association with cancer is unclear. In this study, we found some evidence of an association between Fasciola infection with liver fibrosis and cirrhosis, but little between Fasciola and cancer.
How does the immune system respond to Fasciola hepatica?
The immune response mounted during the early stages of fascioliasis is generally regarded as a mixed Th1/Th2 response where cytokines such as IFNγ, IL-4, IL-10, and TGF-β are elevated.
Where is Fasciola hepatica found in the body?
Adults of Fasciola hepatica are large and broadly-flattened, measuring up to 30 mm long and 15 mm wide. The anterior end is cone-shaped, unlike the rounded anterior end of Fasciolopsis buski. Adults reside in the bile ducts of the liver in the definitive host.
How does the schistosome fluke affect humans?
Schistosomes are water-borne flatworms or blood flukes that enter the human body through the skin. Some symptoms of schistosomiasis include fever, arthralgias, abdominal pain, bloody diarrhea, and hematuria. Ultimately, patients develop heptosplenomegaly, ascites, and lymphadenopathy.
Where does Fasciola hepatica occur?
Fasciola hepatica occurs in the liver of a definitive host and its lifecycle is indirect. Definitive hosts of the fluke are cattle, sheep, and buffaloes. Wild ruminants and other mammals, including humans, can act as definitive hosts as well.
How big is the Fasciola Hepatica?
Fasciola hepatica is one of the largest flukes of the world, reaching a length of 30 mm and a width of 13 mm ( Fasciola gigantica, though, is even bigger and can reach up to 75 mm). It is leaf-shaped, pointed at the back (posteriorly), and wide in the front (anteriorly).
What is the name of the worm that infects the liver?
For the infection, see Fasciolosis. Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic trematode (fluke or flatworm, a type of helminth) of the class Trematoda, phylum Platyhelminthes. It infects the livers of various mammals, including humans, and is transmitted by sheep and cattle to humans the world over.
How does climate affect F. hepatica?
For example, the development of F. hepatica miracidia and larvae, and the reproduction of Galba truncatula, require a temperature range of 10 to 25 °C. In addition, they both require high levels of moisture in the air, as both are at risk of desiccation. Due to this, the prevalence, along with the intensity of infection, of F. hepatica is primarily dependent on rainfall levels and temperature.
What is the species of fasciola?
Fasciola. Species: F. hepatica. Binomial name. Fasciola hepatica. Linnaeus, 1758. Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic trematode (fluke or flatworm, a type of helminth) of the class Trematoda, phylum Platyhelminthes. It infects the livers of various mammals, including humans, ...
Which snails are experimental hosts of F. hepatica?
The list of lymnaeid snails that may serve as natural or experimental intermediate hosts of F. hepatica include: Austropeplea ollula. Austropeplea tomentosa.
Which snails are parasitic in Europe?
hepatica have been described, the parasite develops only in one or two major species on each continent. Galba truncatula is the main snail host in Europe, partly in Asia, Africa, and South America.
Where is Fasciola Hepatica found?
Fasciola hepatica is found on all inhabited continents, in more than 70 countries, particularly where sheep or cattle are raised. Human infections have been reported in parts of Europe, the Middle East, Latin America (e.g., Bolivia and Peru), the Caribbean, Asia, Africa, and rarely in Australia.
How big is a fasciola hepatica?
F. hepatica adults. Adults of Fasciola hepatica are large and broadly-flattened, measuring up to 30 mm long and 15 mm wide. The anterior end is cone-shaped, unlike the rounded anterior end of Fasciolopsis buski. Adults reside in the bile ducts of the liver in the definitive host.
What is the size of a Fasciola egg?
Fasciola hepatica eggs. Eggs of Fasciola spp. are broadly ellipsoidal, are operculated, measure 130–150 µm long by 60–90 µm wide, and are passed unembryonated in feces.
What is the intermediate host of Fasciola spp?
The snail intermediate hosts for Fasciola spp. are in the family Lymnaeidae, particularly species in the genera Lymnaea, Galba, Fossaria, and Pseudosuccinea. At least 20 snail species have been identified as intermediate hosts for one or more Fasciola spp. Snail species may differ with respect to their suitability to serve as intermediate hosts for F. hepatica versus F. gigantica; host ranges for both Fasciola spp. are a subject of ongoing research.
What are the phases of Fasciola spp.?
During the early phase of the infection (usually referred to as the acute phase; also, the migratory, invasive, hepatic, parenchymal, or larval phase), the period when the larval fluke is migrating from the intestines and through the liver parenchyma, larval migration can be associated with inflammation, tissue destruction, and toxic/allergic reactions. Nonspecific symptoms/signs (e.g., abdominal pain, nausea, vomiting, hepatomegaly, malaise, fever, cough) and laboratory abnormalities (e.g., peripheral eosinophilia, elevated transaminase levels) may develop. Occasionally, larval flukes migrate to ectopic sites, such as the lungs, subcutaneous tissue, pancreas, genitourinary tract, eyes, or brain.
Where are F. hepatica and F. gigantica found?
In places where both F. hepatica and F. gigantica occur, each species of fluke has its own species or more of intermediate hosts. Figure A: Galba truncatula, the main intermediate host of F. hepatica throughout most of the fluke's natural range in Europe and western Asia.
How long does it take for a biliary infection to develop?
During the chronic phase of the infection (also referred to as the biliary or adult phase), clinical manifestations, if any, may develop months to years postexposure and include inflammation or blockage of bile ducts or the gallbladder (e.g., cholangitis, cholecystitis), which can be intermittent. Inflammation of the pancreas may also occur.
What are the two types of liver flukes?
There are two types of liver flukes that affect humans. They are Fasciola hepatica (common liver fluke or sheep liver fluke) and Fasciola gigantica.
Is a liver fluke fatal?
Generally, liver fluke infections are not fatal. Those who become infected often survive without any complications because infections are treatable.
Is liver fluke a treatable disease?
Liver fluke infection is treatable. You should consult a professional if you suspect you have a liver fluke infection to prevent complications.
Overview
Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic trematode (fluke or flatworm, a type of helminth) of the class Trematoda, phylum Platyhelminthes. It infects the livers of various mammals, including humans, and is transmitted by sheep and cattle to humans the world over. The disease caused by the fluke is called fasciolosis or fascioliasis, which …
Life cycle
Fasciola hepatica occurs in the liver of a definitive host and its lifecycle is indirect. Definitive hosts of the fluke are cattle, sheep, and buffaloes. Wild ruminants and other mammals, including humans, can act as definitive hosts as well. The life cycle of F. hepatica goes through the intermediate host and several environmental larval stages. Intermediate hosts of F. hepatica are air-breathin…
Morphology and anatomy
Fasciola hepatica is one of the largest flukes of the world, reaching a length of 30 mm and a width of 13 mm (Fasciola gigantica, though, is even bigger and can reach up to 75 mm). It is leaf-shaped, pointed at the back (posteriorly), and wide in the front (anteriorly). The oral sucker is small but powerful and is located at the end of a cone-shape projection at the anterior end. The acetabulum is a larger s…
Prevalence
Currently, F. hepatica has one of the widest geographical spread of any parasitic and vector-borne disease. Originating in Europe, it has expanded to colonize over 50 countries, covering all continents except Antarctica. In contrast, F. gigantica is generally considered more geographically restricted to the tropical regions of Africa, Asia, and the Middle East, with some overlap between the tw…
Parasitic adaptations
F. hepatica's tegument protects it from the enzymes of the host's digestive system, whilst still allowing water to pass through. Free-swimming larvae have cilia and the cercariae have a muscular tail to help them swim through the aquatic environment and also allow them to reach the plants on which they form a cyst. To attach within the host, F. hepatica has oral suckers and body spines. Their p…
Epidemiology
For more information on the epidemiology – see the disease page, fasciolosis
Infection begins when cyst-covered aquatic vegetation is eaten or when water containing metacercariae is drunk. In the United Kingdom, F. hepatica frequently causes disease in ruminants, most commonly between March and December.
Humans become infected by eating watercress or by drinking 'Emoliente', a Peruvian drink that us…
Fasciolosis
Both F. hepatica and F. gigantica can cause fasciolosis. Human symptoms vary depending on whether the disease is chronic or acute. During the acute phase, the immature worms begin penetrating the gut, causing symptoms of fever, nausea, swollen liver (caused by Fh8), skin rashes, and extreme abdominal pain. The chronic phase occurs when the worms mature in the bile duct, and can ca…
Diagnosis
A diagnosis may be made by finding yellow-brown eggs in the stool. They are indistinguishable from the eggs of Fascioloides magna, although the eggs of F. magna are very rarely passed in sheep, goats, or cattle. If a patient has eaten infected liver, and the eggs pass through the body and out via the faeces, a false positive result to the test can occur. Daily examination during a liver-free diet …