Chagas disease, also known as American trypanosomiasis, is a tropical parasitic disease caused by Trypanosoma cruzi. It is spread mostly by insects in the subfamily Triatominae, known as "kissing bugs". The symptoms change throughout the infection. In the early stage, symptoms are typically either not present or mild and may include fever, swollen lymph nodes, headaches, or swelling at the site of the bite. After four to eight weeks, untreated individuals enter the chronic phase of disease, which in most cases does not result in further symptoms. Up to 45% of people with chronic infections develop heart disease 10–30 years after the initial illness, which can lead to heart failure. Digestive complications, including an enlarged esophagus or an enlarged colon, may also occur in up to 21% of people, and up to 10% of people may experience nerve damage.
Q fever or query fever is a disease caused by infection with Coxiella burnetii, a bacterium that affects humans and other animals. This organism is uncommon, but may be found in cattle, sheep, goats, and other domestic mammals, including cats and dogs. The infection results from inhalation of a spore-like small-cell variant, and from contact with the milk, urine, feces, vaginal mucus, or semen of infected animals. Rarely, the disease is tick-borne. The incubation period can range from 9 to 40 days. Humans are vulnerable to Q fever, and infection can result from even a few organisms. The bacterium is an obligate intracellular pathogenic parasite.
Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii, an apicomplexan. Infections with toxoplasmosis are associated with a variety of neuropsychiatric and behavioral conditions. Occasionally, people may have a few weeks or months of mild, flu-like illness such as muscle aches and tender lymph nodes. In a small number of people, eye problems may develop. In those with a weak immune system, severe symptoms such as seizures and poor coordination may occur. If a person becomes infected during pregnancy, a condition known as congenital toxoplasmosis may affect the child.
Toxoplasma gondii is a species of parasitic alveolate that causes toxoplasmosis. Found worldwide, T. gondii is capable of infecting virtually all warm-blooded animals, but felids are the only known definitive hosts in which the parasite may undergo sexual reproduction.
Filariasis is a filarial infection caused by parasitic nematodes (roundworms) spread by different vectors. They are included in the list of neglected tropical diseases.
Veterinary parasitology is a branch of veterinary medicine that deals with the study of morphology, life-cycle, pathogenesis, diagnosis, treatment, and control of eukaryotic invertebrates of the kingdom Animalia and the taxon Protozoa that depend upon other invertebrates and higher vertebrates for their propagation, nutrition, and metabolism without necessarily causing the death of their hosts. Modern parasitology focuses on responses of animal hosts to parasitic invasion. Parasites of domestic animals,, as well as wildlife animals are considered. Data obtained from parasitological research in animals helps in veterinary practice and improves animal breeding. The major goal of veterinary parasitology is to protect animals and improve their health, but because a number of animal parasites are transmitted to humans, veterinary parasitology is also important for public health.
Fasciolosis is a parasitic worm infection caused by the common liver fluke Fasciola hepatica as well as by Fasciola gigantica. The disease is a plant-borne trematode zoonosis, and is classified as a neglected tropical disease (NTD). It affects humans, but its main host is ruminants such as cattle and sheep. The disease progresses through four distinct phases; an initial incubation phase of between a few days up to three months with little or no symptoms; an invasive or acute phase which may manifest with: fever, malaise, abdominal pain, gastrointestinal symptoms, urticaria, anemia, jaundice, and respiratory symptoms. The disease later progresses to a latent phase with fewer symptoms and ultimately into a chronic or obstructive phase months to years later. In the chronic state the disease causes inflammation of the bile ducts, gall bladder and may cause gall stones as well as fibrosis. While chronic inflammation is connected to increased cancer rates, it is unclear whether fasciolosis is associated with increased cancer risk.
Fasciola hepatica, also known as the common liver fluke or sheep liver fluke, is a parasitic trematode of the class Trematoda, phylum Platyhelminthes. It infects the livers of various mammals, including humans, and is transmitted by sheep and cattle to humans all over the world. The disease caused by the fluke is called fasciolosis or fascioliasis, which is a type of helminthiasis and has been classified as a neglected tropical disease. Fasciolosis is currently classified as a plant/food-borne trematode infection, often acquired through eating the parasite's metacercariae encysted on plants. F. hepatica, which is distributed worldwide, has been known as an important parasite of sheep and cattle for decades and causes significant economic losses in these livestock species, up to £23 million in the UK alone. Because of its relatively large size and economic importance, it has been the subject of many scientific investigations and may be the best-known of any trematode species. The closest relative of Fasciola hepatica is F. gigantica. These two flukes are sister species; they share many morphological features and can mate with each other.
Taenia solium, the pork tapeworm, belongs to the cyclophyllid cestode family Taeniidae. It is found throughout the world and is most common in countries where pork is eaten. It is a tapeworm that uses humans as its definitive host and pigs as the intermediate or secondary hosts. It is transmitted to pigs through human feces that contain the parasite eggs and contaminate their fodder. Pigs ingest the eggs, which develop into larvae, then into oncospheres, and ultimately into infective tapeworm cysts, called cysticerci. Humans acquire the cysts through consumption of uncooked or under-cooked pork and the cysts grow into adult worms in the small intestine.
Parasite load is a measure of the number and virulence of the parasites that a host organism harbours. Quantitative parasitology deals with measures to quantify parasite loads in samples of hosts and to make statistical comparisons of parasitism across host samples.
Carrion's disease is an infectious disease produced by Bartonella bacilliformis infection.
Neospora caninum is a coccidian parasite that was identified as a species in 1988. Prior to this, it was misclassified as Toxoplasma gondii due to structural similarities. The genome sequence of Neospora caninum has been determined by the Wellcome Trust Sanger Institute and the University of Liverpool. Neospora caninum is an important cause of spontaneous abortion in infected livestock.
Besnoitia bennetti is a parasite that can cause besnoitiosis infections in donkeys. The range of this organism ranges from Africa to the United States. B. bennettii shares similar characteristics with Toxoplasma, Neospora, and Sarcocystis genera. Lab work on B. bennetti is conducted at biosafety level 1.
Trypanosoma cruzi is a species of parasitic euglenoids. Among the protozoa, the trypanosomes characteristically bore tissue in another organism and feed on blood (primarily) and also lymph. This behaviour causes disease or the likelihood of disease that varies with the organism: Chagas disease in humans, dourine and surra in horses, and a brucellosis-like disease in cattle. Parasites need a host body and the haematophagous insect triatomine is the major vector in accord with a mechanism of infection. The triatomine likes the nests of vertebrate animals for shelter, where it bites and sucks blood for food. Individual triatomines infected with protozoa from other contact with animals transmit trypanosomes when the triatomine deposits its faeces on the host's skin surface while blood feeding. Penetration of the infected faeces is further facilitated by the scratching of the bite area by the human or animal host.
Babesia, also called Nuttallia, is an apicomplexan parasite that infects red blood cells and is transmitted by ticks. Originally discovered by Romanian bacteriologist Victor Babeș in 1888; over 100 species of Babesia have since been identified.
Bartonella bacilliformis is a bacterium, Gram negative aerobic, pleomorphic, flagellated, motile, coccobacillary, 2–3 μm long, 0.2–0.5 μm wide, and a facultative intracellular bacterium.
The pinworm, also known as threadworm or seatworm, is a parasitic worm. It is a nematode (roundworm) and a common intestinal parasite or helminth, especially in humans. The medical condition associated with pinworm infestation is known as pinworm infection (enterobiasis) or less precisely as oxyuriasis in reference to the family Oxyuridae.
Thelaziasis is the term for infestation with parasitic nematodes of the genus Thelazia. The adults of all Thelazia species discovered so far inhabit the eyes and associated tissues of various mammal and bird hosts, including humans. Thelazia nematodes are often referred to as "eyeworms".
Paramphistomum is a genus of parasitic flatworms belonging to the digenetic trematodes. It includes flukes which are mostly parasitising livestock ruminants, as well as some wild mammals. They are responsible for the serious disease called paramphistomiasis, also known as amphistomosis, especially in cattle and sheep. Its symptoms include profuse diarrhoea, anaemia, lethargy, and often result in death if untreated. They are found throughout the world, and most abundantly in livestock farming regions such as Australia, Asia, Africa, Eastern Europe, and Russia.
Eimeria zuernii is a species of the parasite Eimeria that causes diarrheic disease known as eimeriosis in cattle, and mainly affects younger animals. The disease is also commonly referred to as coccidiosis. The parasite can be found in cattle around the globe.
