Cysticercosis: Difference between revisions
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===Infectious dose, incubation, and colonization=== | ===Infectious dose, incubation, and colonization=== | ||
The infectious dose required to cause cysticercosis is relatively unknown (15). The median incubation period for cysticercosis is estimated to be about 3.5 years (13) and can range from 10 days to 10 years (14). A person who has consumed <i>T. solium</i> may go for years without having any symptoms of infection. This is due to the fact that cysticerci often only cause symptoms when they are dying or become large enough to interfere with vital organs. (14) Furthermore, it normally takes 2-3 months for the eggs to develop into cysticerci (15). | |||
Upon consumption of <i>T. solium</i> eggs, the oncospheres hatch in the intestine and then penetrate the intestinal wall. <i>T. solium</i> contain sharp, spine hooks and four suckers that help them adhere to and penetrate the gut wall (17). They then migrate to skeletal muscle, the brain, eyes, subcutaneous tissues, and other places where they develop into cysticerci. (16) | |||
===Epidemiology=== | ===Epidemiology=== | ||
===Virulence factors=== | ===Virulence factors=== | ||
Revision as of 22:42, 23 July 2014
Etiology/Bacteriology
Taxonomy
| Domain = Eukaryota | Phylum = Platyhelminthes | Class = Cestoda | Order = Cyclophyllidea | Family = Taeniidae | Genus = Taenia | species = T. solium
Description
Cysticercosis is an infectious disease that is caused by the larvae of Taenia solium. T. solium is a two-host zoonotic cestode whose adult stage consists of a 2-4 meter long tapeworm. The only known final host for this adult stage is humans, specifically in the small intestine. The intermediate host is the pig, so part of the T. solium life cycle takes place in that host prior to causing taeniasis in humans. Taeniasis is a parasitic infection caused by the presence of tapeworms in the intestine. A person with taeniasis is capable of infecting themselves or others with cysticercosis through fecal-oral transmission. Cysticercosis is transmitted by eating food or drinking water that is contaminated with T. solium eggs. 2-3 months after ingestion, the eggs develop into cysticerci, which are cysts formed by T. solium larvae. The location of the cysts throughout the body determines the symptoms that are demonstrated, diagnoses performed, and treatment used. If the cysts are located in the central nervous system, the infection is specifically called neurocysticercosis.
Cysticercosis is most prevalent in parts of Africa, Asia, Mexico, and Central and South America. However, it is a worldwide issue with about 50 million people having the infection. Because of its fecal-oral transmission, it is important to prevent consumption of contaminated food and water and practice proper hand washing techniques. If the parasite does infect a host, the host immune response will attempt to remove the infection through innate and adaptive responses. Inflammation is a key to the host immune response, yet it can hurt the host as much as it benefits it.
Pathogenesis
Transmission
Larvae of the tapeworm Taenia solium are what cause cysticercosis. If a person becomes contaminated with an adult tapeworm, an infection called taeniasis, they can shed T. solium eggs in their stool. These eggs must then be consumed through fecal-oral route transmission, which can occur by drinking water or eating food that is contaminated with T. solium eggs, or by putting a fecal contaminated object in one’s mouth. Due to this form of transmission, it is possible for autoinfection to occur. If a person has taeniasis, they can infect themselves with the T. solium eggs they shed and thus develop cysticercosis. (12)
Infectious dose, incubation, and colonization
The infectious dose required to cause cysticercosis is relatively unknown (15). The median incubation period for cysticercosis is estimated to be about 3.5 years (13) and can range from 10 days to 10 years (14). A person who has consumed T. solium may go for years without having any symptoms of infection. This is due to the fact that cysticerci often only cause symptoms when they are dying or become large enough to interfere with vital organs. (14) Furthermore, it normally takes 2-3 months for the eggs to develop into cysticerci (15).
Upon consumption of T. solium eggs, the oncospheres hatch in the intestine and then penetrate the intestinal wall. T. solium contain sharp, spine hooks and four suckers that help them adhere to and penetrate the gut wall (17). They then migrate to skeletal muscle, the brain, eyes, subcutaneous tissues, and other places where they develop into cysticerci. (16)
Epidemiology
Virulence factors
Clinical features
Symptoms
Morbidity and Mortality
Diagnosis
Treatment
Prevention
Host Immune Response
References
References
Created by {Jordan Voth}, students of Tyrrell Conway at the University of Oklahoma.
