Infectivity of Cryptosporidium hominis and Cryptosporidium parvum genotype 2 isolates in immunosuppressed Mongolian gerbils.

One-month-old dexamethasone-immunosuppressed Mongolian gerbils were challenged with 1 oocyst to 2 × 10 5 oocysts from two isolates genotyped as Cryptosporidium hominis and C. parvum (genotype 2), respectively. A similar dose-dependent gut infection was obtained, and the initial genotype maintained for 21 to 22 days. The data suggest that immunosuppressed gerbils provide a reliable rodent model of persistent C. hominis infection.