Part 3a - Cryptosporidium: another gut pathogen?

Abstract

This chapter describes the presence of cryptosporidium in malnourished children. The protozoan parasite Cryptosporidium is known to cause enteritis in several animal species. In humans it was first recognized as a cause of diarrhea in immunodeficient individuals, however, is at present known also to affect normal individuals. Its relatively recognition in human disease means that many laboratories are not yet set up to look for this organism, so there is very little information about its importance as a cause of diarrhea in well-nourished children. Malnourished children theoretically would be more susceptible because of secondary immune deficiency. A report from Rwanda showed Cryptosporidium to be associated with diarrhea after measles, in children with presumed depression of the cellular immune response. It is found Cryptosporidium oocysts in 4.3% of stools from rural Costa Rican children with diarrhea, and none in controls. It seems that Cryptosporidium belongs to a single species genus. Calf Cryptosporidium has been shown to infect lambs, pigs, rats, mice, guinea pigs and chickens. Human Cryptosporidium infects lambs. Several human cases have resulted from contact with infected calves. Strategies for the prevention will therefore require consideration of animal hosts and their interaction with indigenous people.