Table 1.

Baseline characteristics and serological results.

	9–11 mo	3–4 y	7–9 y	15 y	Total
Baseline characteristics
Enrolled	100	100	100	100	400
Colombo	37	34	33	33	137
Badulla	30	32	33	34	129
Killinochi	33	34	34	33	134
Sex (% female); n/N (%)
Colombo	20/37 (54%)	14/34 (41%)	13/33 (39%)	11/33 (33%)	58/137 (42%)
Badulla	11/30 (37%)	15/32 (47%)	17/33 (52%)	15/33 (44%)	58/129 (45%)
Killinochi	12/33 (36%)	15/34 (44%)	14/41 (41%)	14/33 (42%)	55/134 (41%)
Fully vaccinated with OPV (%) according to age; n/N (%)
Colombo	37/37 (100%)	34/34 (100%)	33/33 (100%)	33/33 (100%)	137/137 (100%)
Badulla	29/30 (97%)	32/32 (100%)	33/33 (100%)	34/34 (100%)	128/129 (99%)
Killinochi	33/33 (100%)	34/34 (100%)	34/34 (100%)	30/33 (91%)	131/134 (98%)
Average monthly income per household <$75 (%);n/N (%)
Colombo	0/37 (0%)	0/34 (0%)	1/33 (3%)	0/33 (0%)	1/137 (1%)
Badulla	1/30 (3%)	0/32 (0%)	3/33 (9%)	2/34 (6%)	6/129 (5%)
Killinochi	12/33 (36%)	6/34 (18%)	0/34 (0%)	3/33 (9%)	21/134 (16%)
Serological results		–	–	–	–
Poliovirus Type 1
% Positive (95% CI)	96 (90.1, 98.9)	99 (94.6, 100)	99 (94.6, 100)	97 (91.5, 99.4)	98 (95.6, 98.9)
Median titer, (95% CI)	⩾1448 (⩾1448, ⩾1448)	724.1 (455, 1152)	325 (181, 455)	90.5 (56, 144)	455 (455, 724)
Poliovirus Type 2
% Positive (95% CI)	98 (93, 99.8)	97 (91.5, 99.4)	99 (94.6, 100)	100 (96.4, 100)	99 (96.6, 99.4)
Median titer, (95% CI)	⩾1448 (⩾1448, ⩾1448)	576 (408, 724)	227 (144, 455)	113 (90, 181)	455 (362, 576)
Poliovirus Type 3
% Positive (95% CI)	95 (88.7, 98.4)	90 (82.4, 95.1)	77 (67.5, 84.8)	75 (65.3, 83.1)	84 (80.3, 87.7)
Median titer, (95% CI)	910 (576, 1152)	113 (64, 227)	36 (18, 90)	28 (11, 45)	91 (72, 144)

CI = confidence interval; OPV = oral poliovirus vaccine.