Although the genus Cryptosporidium, small coccidian parasite infecting
the microvilli of intestinal and respiratory epithelial cells of many
vertebrate species, was named in 1910, it was not considered a pathog
en for over half a century. First reports on its association with diar
rhea in calves in the early 70'-ies, later in other species, and parti
cularly in patients with acquired immunodeficiency syndrome (AIDS) in
the late 70'-ies, prompted the need for more information on this paras
ite. Until 1980 hardly 30 papers were published on Cryptosporidium spp
. However, their number exceeded 900 Publications by 1990. Cryptospori
dia are now recognized as a globally important cause of mainly gastroi
ntestinal illness in several vertebrate species. This paper reviews fo
r the Hungarian readers selected topics on the validity of Cryptospori
dium spp., the host specificity, life cycle, the prevalence in differe
nt host species, epidemiology, pathogenesis, clinical features, immuni
ty, diagnosis, attempts and failures of chemotherapy, and prevention.