Table 2.

HPV prevalence rates, prevalence ratios, and vaccine effectiveness by HPV type

		Baseline survey		Repeat survey		Adjusted vaccine effectiveness (95% CI)*
		Number assessed	HPV-positive	Number assessed	HPV-positive
HPV6, 11, 16, and 18
All ages
	Overall†	1501	173 (12%)	1639	89 (5%)	47% (31 to 60)
	Indirect‡	1478	169 (11%)	979	69 (7%)	32% (9 to 49)
	Total§	1478	169 (11%)	638	20 (3%)	70% (52 to 82)
Age 17–23 years
	Overall†	1092	134 (12%)	1191	63 (5%)	52% (35 to 65)
	Indirect‡	1072	130 (12%)	585	43 (7%)	36% (8 to 55)
	Total§	1072	130 (12%)	597	20 (3%)	69% (50 to 81)
Age 24–29 years
	Overall†	409	39 (10%)	448	26 (6%)	37% (−5 to 62)
	Indirect‡	406	39 (10%)	394	26 (7%)	30% (−16 to 58)
	Total§	406	39 (10%)	41	0	100% (NA)
Other alpha-9 HPV types¶
All ages
	Overall†	1501	205 (14%)	1639	168 (10%)	28% (11 to 41)
	Indirect‡	1478	200 (14%)	979	105 (11%)	26% (6 to 42)
	Total§	1478	200 (14%)	638	63 (10%)	25% (−1 to 45)
Age 17–23 years
	Overall†	1092	151 (14%)	1191	123 (10%)	28% (8 to 43)
	Indirect‡	1072	146 (14%)	585	64 (11%)	27% (2 to 46)
	Total§	1072	146 (14%)	597	59 (10%)	24% (−5 to 44)
Age 24–29 years
	Overall†	409	54 (13%)	448	45 (10%)	26% (−10 to 50)
	Indirect‡	406	54 (13%)	394	41 (10%)	26% (−11 to 51)
	Total§	406	54 (13%)	41	4 (10%)	−9% (−145 to 66)

Data are n or n (%) unless otherwise stated. HPV=human papillomavirus. NA=not applicable.

^*Adjusted for age, level of education, HIV status, and lifetime number of sexual partners.

^†Entire baseline survey group compared with entire repeat survey group.

^‡Unvaccinated baseline survey group compared with entire repeat survey group.

^§Unvaccinated baseline survey group compared with vaccinated repeat survey group.

^¶Other alpha-9 types (HPV31, 33, 35, 52, and 58).