Submitted to: International Congress of Protozoologists
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2005
Publication Date: June 3, 2005
Citation: Fayer, R. 2005. Cryptosporidium overview: biology, pathology, and epidemiology [abstract]. International Congress of Protozoologists for East Coast. Handout p.1.
Members of the genus Cryptosporidium are monoxenous, intracellular, extracytoplasmic, obligate parasites of vertebrates, primarily infecting the gastrointestinal tract. Fifteen species and over 30 genotypes have been identified in more than 150 species of hosts. Humans serve as hosts for five zoonotic species and two zoonotic genotypes, the most prevalent being C. hominis and C. parvum. Based on published reports C. parvum appears to have the greatest host range of in the genus, although many reports have relied on microscopic identification of the oocyst stage without supporting molecular data, and the oocysts of many species and genotypes are indistinguishable. Isolates of this species have shown great variability in virulence and age related prevalence for certain hosts. Oocysts from human and animal feces are spread by direct contact with infected humans and animals and distributed through the environment primarily by water that eventually contaminates ponds, lakes, rivers, agricultural irrigation systems, and coastal waters. Numerous outbreaks have been reported associated with contaminated swimming pools and with improper treatment of drinking water. There are no vaccines, and only one drug has been approved for treatment. However, the genomes of C. parvum and C. hominis have been recently sequenced, providing information that can be applied to the development of pharmaceuticals and possibly immunity-based prevention strategies.