TY - JOUR
T1 - Virulence of three distinct Cryptosporidium parvum isolates for healthy adults
AU - Okhuysen, Pablo C.
AU - Chappell, Cynthia L.
AU - Crabb, Joseph H.
AU - Sterling, Charles R.
AU - DuPont, Herbert L.
N1 - Funding Information:
Grant Support: US Environmental Protection Agency (CR-819814 and CR-824759), National Institutes of Health (R01 AI 41735-01 and RR-02558), ImmuCell Corporation, and The Food and Drug Administration (FD-U-001621-01).
PY - 1999
Y1 - 1999
N2 - 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 IC50 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 versus Iowa, P = .002 or UCP, P = .019. Isolates also differed significantly (P = .045) in attack rate between TAMU (86%) and Iowa (52%) or UCP (59%). A trend toward a longer duration of diarrhea was seen for the TAMU (94.5 h) versus UCP (81.6 h) and Iowa (64.2 h) isolates. C. parvum isolates of the C genotype differ in their infectivity for humans.
AB - 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 IC50 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 versus Iowa, P = .002 or UCP, P = .019. Isolates also differed significantly (P = .045) in attack rate between TAMU (86%) and Iowa (52%) or UCP (59%). A trend toward a longer duration of diarrhea was seen for the TAMU (94.5 h) versus UCP (81.6 h) and Iowa (64.2 h) isolates. C. parvum isolates of the C genotype differ in their infectivity for humans.
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U2 - 10.1086/315033
DO - 10.1086/315033
M3 - Article
C2 - 10479158
AN - SCOPUS:0033394114
SN - 0022-1899
VL - 180
SP - 1275
EP - 1281
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
IS - 4
ER -