Toxoplasma cyst containing toxoplasma organisms. From the VCU department of Pathology, http://www.pathology.vcu.edu/education/microbiology/lab2.6.html
What Is Toxoplasma gondii?
It infects more than half of the world’s population. It has a wide variety of intermediate hosts, is highly transmissible, and can even alter an organisms behavior in order to increase it’s own spread. In sum, it has all the trappings of the most successful known parasite. Toxoplasma gondii, also known as Toxoplasma, is a parasite in the protozoan phylum Apicomplexa that is present in most animals and birds. It is an obligate, intracellular parasite that has both asexual and sexual lifecycle phases. It has a nonseasonal worldwide distribution, and the oocysts tend to fare better in tropical climates with warmer soil. Most natural infections are acquired by ingesting undercooked meat containing tissue cysts or from food contaminated by cat feces.