Killer Protists
By: Dillon Petersen
Plasmodium
Plasmodium is a large genus of parasitic protozoa. Infection with these protozoans is known as malaria. The parasite always has two hosts in its life cycle: a mosquito vector and a vertebrate host. The genus contains about 200 species in divided into several subgenera. At least ten species infect humans; other species infect other animals, including birds, reptiles and rodents.
Trypanosoma
Giardia
Giardia is a microscopic parasite that causes the diarrheal illness known as giardiasis. Giardia is found on surfaces or in soil, food, or water that has been contaminated with feces from infected humans or animals.
Giardia is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it tolerant to chlorine disinfection. While the parasite can be spread in different ways, water (drinking water and recreational water) is the most common method of transmission.
Giardia infections usually clear up within a few weeks. But you may have intestinal problems long after the parasites are gone. Several drugs are generally effective against giardia parasites, but not everyone responds to them. Prevention is your best defense.
Dinoflagellates
Dinoflagellates are protists which have been classified using both the International Code of Botanical Nomenclature and the International Code of Zoological Nomenclature, approximately half living dinoflagellate species are autotrophs possessing chloroplasts and half are non-photosynthesising heterotrophs. It is now widely accepted that the ICBN should be used for their classification. Dinoflagellates and their cysts belong to the Division Pyrrhophyta, Class Dinophycaea, the related Class Ebriophyceae includes the ebridians which have internal siliceous skeletons, are extant and have a fossil record beginning in the Palaeocene.