AIDS—Acquired Immunodeficiency Syndrome—a disease of the human immune system that is characterized cytologically especially by reduction in the numbers of CD4-bearing helper T cells to 20 percent or less of normal rendering the subject highly vulnerable to life-threatening conditions (as Pneumocystis carinii pneumonia) and to some that become life-threatening (as Kaposi's sarcoma) and that is caused by infection with HIV commonly transmitted in infected blood and bodily secretions (as semen) especially during illicit intravenous drug use and sexual intercourse.
Endemic—prevalent in or peculiar to a particular locality, region, or people.
Enteric—relating to the intestines.
HAART—Highly Active Anti-retroviral Therapy—a combination of reverse transcriptase inhibitors and protease inhibitors which suppresses the HIV virus, but does not clear the virus from the patient’s body.**
Oocyst—a thick-walled structure in which sporozoan zygotes develop and that serves to transfer them to new hosts.*
Protozoa—any of a phylum or subkingdom (Protozoa) of chiefly motile and heterotrophic unicellular protists (as amoebas, trypanosomes, sporozoans, and paramecia) that are represented in almost every kind of habitat and include some pathogenic parasites of humans and domestic animals.
Sporozoite—Any of the minute undeveloped sporozoans produced by multiple fission of a zygote or spore, especially at the stage just before it infects a new host cell.*
Zoonotic—communicable from animals to humans under normal conditions.
(All definitions are from Merriam-Webster Dictionary except *from American Heritage Dictionary and **from National Institute of Allergy and Infectious Disease)