Research Article

Selective Intermittent Preventive Treatment of Vivax Malaria: Reduction of Malaria Incidence in an Open Cohort Study in Brazilian Amazon

Table 1

Demographic characteristics and malaria baseline survey in the study’s communities, in 2007 and 2008.

Characteristics Group Locality
São SebastiãoVila AmazonasCachoeira do Teotônio

0–532 (11.4)20 (10.1)36 (9.2)
Age group (%)6–1573 (26.2)46 (23.2)93 (23.7)0.737
>15174 (62.4)132 (66.7)263 (67.1)
Total279198392
Gender (%)Male149 (53.4)119 (60.1)218 (55.6) 0.344
Female130 (46.6)79 (39.9)174 (44.4)
Previous malaria cases within age group (%)None36 (12.9)23 (11.6)61 (15.6) 0.594
1–494 (33.7)59 (29.8)121 (30.9)
5–1089 (31.9)62 (31.3)113 (28.8)
>1060 (21.5)54 (27.3)97 (24.7)
Living in endemic area, in years, Mean ± SD (CI 95% mean)22.89 ± 17.92 (20.79–25.00)13.86 ± 14.23 (11.86–15.85)7.88 ± 10.81 (6.81–8.95)<0.001
Malaria incidence in 2007, before the study cases/100 inhabitants (CI 95%)24.9 (19.7–30.7)28.5 (22.1–35.6)26.6 (22.4–31.3)0.824
P. vivax prevalence % (CI 95%)19.0 (14.4–24.4)23.8 (17.9–30.6)21.6 (17.7–26.0)0.626
P. vivax prevalence proportion % (CI 95%)76.3 (64.2–85.8)83.7 (71.3–92.1)81.2 (72.7–87.9)0.945
P. vivax in APC prevalence % (CI 95%)6.5 (4.0–9.8)15.7 (11.1–21.2)11.7 (8.8–15.2)0.014
P. falciparum prevalence % (CI 95%)5.9 (3.4–9.5)4.7 (2.2–8.6)5.0 (3.1–7.6)0.335
P. falciparum prevalence proportion % (CI 95%)23.7 (14.2–35.8)16.3 (7.9–28.7)18.8 (12.1–27.3)0.715
P. falciparum APC prevalence % (CI 95%)1.1 (0.3–2.9)6.1 (3.3–10.1)1.3 (0.5–2.8)<0.001

SD: standard deviation. CI 95%: confidence interval. : value. APC: asymptomatic Plasmodium carrier (Apr/2008).