The coccidian oocyst: a tough nut to crack!

Trends Parasitol. 2006 Sep;22(9):416-23. doi: 10.1016/ Epub 2006 Jul 21.


Coccidian parasites are transmitted between hosts by the ingestion of food or water contaminated with oocysts, followed by the release of infectious sporozoites and invasion of the gastro-intestinal tract. In the external environment, sporozoites are protected from desiccation and chemical disinfection by the oocyst wall. This unique structure guarantees successful disease transmission and is as vital to the coccidian parasite as the exoskeleton is to insects--without it they would die. Here, we revisit the early work and combine it with newer molecular data to describe our present understanding of the coccidian oocyst wall.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Coccidia / genetics
  • Coccidia / physiology*
  • Coccidiosis / parasitology
  • Coccidiosis / transmission*
  • Food Parasitology*
  • Host-Parasite Interactions
  • Humans
  • Life Cycle Stages / physiology
  • Oocysts / chemistry
  • Oocysts / metabolism
  • Oocysts / ultrastructure*
  • Protozoan Proteins / metabolism*


  • Protozoan Proteins