No. (%) of subjects challenged with No. (%) of subjects challenged with
Characteristics Inoculum 1 (N=15) Inoculum 2 (N=33) P
Sex 0.48a
Male 7(46.7) 20(60.6)
Female 8(53.3) 13(39.4)
Race/Ethnicity 0.019b
African American 4(26.7) 22(66.6)
White 11(73.3) 9(27.3)
Other 0(0) 2(6.1)
Secretor Status 0.81b
Positive 11(73.3) 25(75.7)
Negative 4(26.7) 8(24.3)
Age (years) 30.7(9.3)c 32.9(9.3)c 0.35d