Table 3.

Mean Density of Pneumococcal Carriage in Infected Individuals During the Prevaccination and Postvaccination Cross-Sectional Surveys in Vaccinated Villages and Control Villages, by Age at Sample Collection

	Age ≤ 5 Years				Age > 5 Years
Study Arm, Serotype Group	Prevaccination	Postvaccinationa	Difference (95% CI)	P	Prevaccination	Postvaccinationa	Difference (95% CI)	P	Pintb
Vaccinated villages
VT	2.87	2.48	−0.39 (−0.82 to 0.04)	.071	2.14	1.78	−0.36 (−0.64 to −0.07)	.021	.902
NVT	2.72	2.08	−0.64 (−1.28 to 0.01)	.052	2.48	1.91	−0.57 (−0.90 to −0.25)	.003	.582
All	2.57	2.11	−0.46 (−0.97 to 0.04)	.067	2.44	1.88	−0.56 (−0.83 to −0.29)	.001	.702
Control villages
VT	2.70	1.94	−0.76 (−1.49 to −0.04)	.042	2.42	1.78	−0.64 (−1.00 to −0.28)	.003	.685
NVT	2.90	2.03	−0.87 (−1.46 to −0.28)	.010	2.45	1.74	−0.71 (−1.06 to −0.36)	.001	.895
All	2.76	1.99	−0.78 (−1.19 to −0.36)	.002	2.44	1.75	−0.69 (−1.01 to −0.37)	.001	.696

Data are mean densities, expressed in arbitrary units, as defined in the Methods section.

Abbreviations: CI, confidence interval; NVT, non–vaccine-type pneumococci; VT, vaccine-type pneumococci.

^a Data are for all 3 postvaccination cross-sectional surveys combined.

^b P value for interaction between group (control or vaccinated) and age category.