| Description:
|
Cryptosporidium inhabits
the epithelium of the respiratory and digestion systems
of reptiles, birds, and mammals. Infections of the ileum
are most common, but gastric, respiratory, and conjunctive
infections have been observed in immunosuppressed hosts.
Many species have been described. Most species may be
relatively host specific. Those found in reptiles and
birds apparently do not infect mammals. Only two species
are recognized in mammals on the basis of the very small
oocyte size, namely C. parvum and Cryptosporidium spp.
Oocysts are often difficult to demonstrate in the feces
without special techniques. The biology Cryptosporidium
spp. is not well known and its host range is limited.
In contrast, C. parvum is by far the most commonly occurring
species in mammals and, similar to Toxoplasma, has a
wide mammalian host range. In a clinical and postmortem
study in domestic and feral cats, the prevalence of
infection was 5% and 12%, respectively. In rural cats
from the surrounding area, the prevalence was 12%. Oocytes
of cryptosporidium are spread via the fecal-oral route.
Fecal contamination of food or drinking water is a common
source of infection. |
