Table 2.

Occurrence of Symptomatic Vibrio cholerae Infection Among Household Contacts by Age and Baseline Titer^a

	Day 2 Titer ≤20			Day 2 Titer 40–80			Day 2 Titer ≥160
Age (Years)	N	N Symptomatic	Percent Symptomatic (95% CI)	N	N Symptomatic	Percent Symptomatic (95% CI)	N	N Symptomatic	Percent Symptomatic (95% CI)
<5	30	6	20.0 (7.7–38.6)b	8	1	12.5 (0.3–52.7)b	12	0	0.0 (0.0–26.5)b
5–15	100	16	16.0 (10.1–24.4)	47	3	6.4 (1.3–17.5)b	81	3	3.7 (0.8–10.4)b
≥16	172	19	11.0 (7.2–16.6)	144	10	6.9 (3.8–12.3)	232	6	2.6 (1.2–5.5)

Abbreviations: CI, confidence interval.

^aConfidence intervals represent the expected range if the study population was repeatedly resampled.

^bExact CI calculated using exact methods given small numbers.