Coccidiosis is the disease caused by coccidian infection. Coccidiosis is a parasitic disease of the intestinal tract of animals, caused by coccidian protozoa. The disease spreads from one animal to another by contact with infected faeces or ingestion of infected tissue. The primary symptom is usually watery diarrhoea, dysentery and weight loss. It usually presents in young animals which are living in overcrowded and unhygienic conditions. Most adult animals infected with coccidia are asymptomatic; however, immuno-compromised animals may suffer severe symptoms, including death.
Pathogenicity of coccidiosis is related to the size of the endogenous stages, the location of the infection in the mucosa and the site of infection. For example, infection in the small intestine can lead to compensation whereas infection in the large intestine will affect water absorption. If mucosal stem cells are affected, it will cause villous atrophy and a prolonged recovery.
While coccidian organisms can infect a wide variety of animals, including humans, birds, and livestock, they are usually species-specific. One well-known exception is toxoplasmosis, caused by Toxoplasma gondii.
Species specific descriptions of the disease are found on individual wikivet pages.