Virulence of three distinct Cryptosporidium parvum isolates for healthy adults.

@article{Okhuysen1999VirulenceOT,
  title={Virulence of three distinct Cryptosporidium parvum isolates for healthy adults.},
  author={P. Okhuysen and C. Chappell and J. Crabb and C. Sterling and H. DuPont},
  journal={The Journal of infectious diseases},
  year={1999},
  volume={180 4},
  pages={
          1275-81
        }
}
The infectivity of three Cryptosporidium parvum isolates (Iowa [calf], UCP [calf], and TAMU [horse]) of the C genotype was investigated in healthy adults. After exposure, volunteers recorded the number and form of stools passed and symptoms experienced. Oocyst excretion was assessed by immunofluorescence. The ID50 differed among isolates: Iowa, 87 (SE, 19; 95% confidence interval [CI], 48.67-126); UCP, 1042 (SE, 1000; 95% CI, 0-3004); and TAMU, 9 oocysts (SE, 2.34; 95% CI, 4.46-13.65); TAMU… Expand
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