Table 6. Incidence rates (IR) per 1,000 person-years of dengue infections in the cohort in Yucatan, Mexico by age, gender, and city (N = 1,890).

	Person-years at risk (N)	Dengue infections	IR (95%CI)
All participants	2271(1890)	83	36.55 (29.3, 45.1)
Age (Years)
≤ 8	692.84 (624)	35	50.5 (35.7, 69.5)
9–14	359.74 (305)	17	47.3 (28.5, 74.1)
15–19	92.91 (76)	9	96.9 (47.2, 177.8)
20–49	959.68 (757)	23	23.9 (15.6, 35.4)
≥ 50	166.11 (128)	5	30.1 (11.0, 66.7)
Gender
Male	984.49 (882)	27	27.4 (18.4, 39.4)
Female	1286.79 (1008)	62	48.2 (37.3, 61.4)
City
Merida	1248.14 (1032)	51	40.9 (30.7, 53.3)
Progreso	481.76 (401)	27	56.1 (37.7, 80.4)
Ticul	540.38 (457)	11	20.4 (10.7, 35.4)
Prior exposure to dengue
Naïve	645.80 (542)	74	114.6 (90.6, 143)
Non-naïve	1625.20 (1348)	9	5.5 (2.7, 10.1)