Oocyst

Slovak term: Slovenský termín

1. A structure that is produced by some coccidian protozoa (i.e. Cryptosporidium) as a result of sexual reproduction during the life cycle. The oocyst is usually the infectious and environmental stage, and it contains sporozoites (WHO 2006).

Example

In the infected animal, Cryptosporiuim multiplies in the gastrointestinal tract. The animal then excretes oocysts of the parasite in its faeces in very large numbers (United Kingdom Group of Experts 1998).

Oocysts excreted in the feces of infected humans and animals are generally 10e7 oocysts per gram of feces (Smith and Rose 1990).

References

• WHO (2006) Guidelines for the safe use of wastewater, excreta and greywater.
• Smith HV and Rose JB (1990) Waterborne cryptosporidiosis. Parasitol. Today, 6: 8–12.
• United Kingdom Group of Experts (1998) Cryptosporidium in Water Supplies. Third Report of the Group of Experts to the Department of the Environment, Transport and the Regions and the Department of Health.

Links

• WHO — The Health and Environment Lexicon