Does Insecticide Treated Mosquito Nets (ITNs) prevent clinical malaria in children aged between 6 and 59 months under program setting?

Inconsistent use of the mosquito nets and other social and technical factors were shown to influence efficacy of mosquito nets at field trials. But to date, experience with local factors influencing effectiveness of ITN programs remain very limited. The objective of this study was to assess the effectiveness of ITNs for preventing clinical malaria in under-five children of Omo Nada Woreda, Jimma Zone South West Ethiopia. Matched case-control study was conducted in the catchments population of Asendabo and Nada health centers, Omo Nada Woreda, South West Ethiopia on a sample of 273 under-five children. Each case of fever and parasitemia in a child was paired with two controls. Cases and controls were compared with regard to ITN ownership and other factors assessed by a pre-coded, pre-tested structured questionnaire. Data was analyzed using EPI-INFO version 3.3.2 software. To control the effect of confounding variables, conditional logistic regression model was used. Sleeping under the mosquito net the night (OR = 8.28 95% CI: 0.96, 71.1) and the week (OR = 2.41 95% CI: 0.41, 14.0) before the survey date were strongly, but not significantly associated with clinical malaria. Mosquito net possession and appropriate utilization of mosquito net were not associated with clinical malaria. In the comparison of cases with all the controls rolling out of mosquito net & corrugated iron roof were found to be independent predictors of clinical malaria. Knowledge about the sign and symptoms of malaria and its modes of transmission were also independent predictors of clinical malaria in comparison of cases with health center and community controls, respectively. With the presence of many programmatic deficiencies like poor ITN distribution and re-treatment services, ITNs were not significantly associated with clinical malaria in under-five children when used during low-transmission period. Further research using a large sample size is required. In line with ITN scale up, information Education Communication (IEC) about the preventive practices against malaria, causes of malaria, treatment and sign and symptoms of malaria should be given to the community.