Toxoplasmosis
Say it: tok-soh-plaz-MOH-sis
Toxoplasmosis is an infection with the protozoan Toxoplasma gondii, usually mild but dangerous in pregnancy and for people with weakened immunity.
Definition
What is toxoplasmosis?
Toxoplasmosis is the illness caused by Toxoplasma gondii, a single-celled protozoan parasite related to the malaria parasite. Cats, wild and domestic, are its definitive hosts: only in their intestines does it reproduce sexually, and a newly infected cat sheds huge numbers of oocysts in its feces for a few weeks. Almost any warm-blooded animal can serve as an intermediate host, carrying the parasite as tissue cysts in muscle and brain. People become infected by eating undercooked meat containing cysts, by swallowing oocysts from soil, cat litter, unwashed produce or water, or before birth from a mother infected during pregnancy.
Infection is very common worldwide. In healthy people it usually causes no symptoms or a mild, flu-like illness with swollen lymph nodes, after which the parasite stays dormant in cysts for life. It becomes serious when immunity is weak, as in advanced HIV infection or after a transplant, because cysts can reactivate and inflame the brain. A first infection during pregnancy can cause miscarriage or damage to the baby's brain and eyes, and the parasite is also a common cause of inflammation of the retina.
Diagnosis rests mainly on blood tests for antibodies, PCR for parasite DNA and brain imaging. When treatment is needed, it usually combines pyrimethamine with sulfadiazine, and spiramycin is used early in pregnancy.
Word parts
Where does the word “toxoplasmosis” come from?
- toxo-
- bow, arcGreek toxon
- -plasm-
- something formedGreek plasma
- -osis
- disease, conditionGreek -osis
Related
Terms that go with it
- ProtozoaProtozoa are single-celled eukaryotes that do not photosynthesize, usually move on their own and feed on other organisms or organic matter.
- ParasiteA parasite is a living thing that makes its home on or inside a host organism and feeds from it, usually causing the host harm.
- ZoonosisA zoonosis is an infectious disease that passes between animals and people, caused by a virus, bacterium, parasite or fungus carried by animals.
- HIVHIV is a retrovirus that infects and destroys CD4 helper T cells, weakening the immune system and, without treatment, leading to AIDS.
- PlasmodiumPlasmodium is a genus of single-celled parasites, spread by Anopheles mosquitoes, that infect liver and red blood cells and cause malaria.
- Polymerase chain reactionThe polymerase chain reaction (PCR) is a lab technique that copies one chosen stretch of DNA over and over until there are billions of copies.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- CDC: About Toxoplasmosis
- MedlinePlus: Toxoplasmosis
- OpenStax Microbiology, 25.4 Parasitic Infections of the Circulatory and Lymphatic Systems
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