Domestic Prevalence of Malaria Vectors and Self-reported Malaria Episode with Respect to Ownership and Utilization of Long-lasting Insecticidal Nets in Selected Resettlement and Indigenous Villages in Sasiga District, Western Ethiopia

Abstract

Agricultural resettlement of none-immune population in malaria endemic lowlands has become one of the key challenges to malaria control and elimination efforts in Ethiopia. Long-lasting insecticidal nets (LLINs) are currently the best malaria control intervention in the country. We assessed indoor prevalence of malaria vectors and the disease incident with respect to possession and utilization of LLINs in selected resettlement and indigenous villages in Sasiga district, western Ethiopia. Adult mosquitoes were monitored indoors and outdoors from randomly selected samples of 12 houses using Centers for Disease Control and Prevention light traps (CDC-LTs). Whereas LLINs possession and utilization survey was conducted concurrently with household survey of self-reported malaria episode. The study was conducted once during dry season (December-February), minor malaria transmission season (March-May) and the major transmission season (September-December) in 2011-2012. Data were analysed using One-way analysis of variance, logistic regression (odd ratio) and descriptive statistics via SPSS version 20.0. The results were considered significant at P < 0.05. Anopheles gambiae s.l. constituted 81.1% (n=270) of the anopheline collection and the rest 18.9% (n=63) were Anopheles coustani and Anopheles cinereus. The mean indoor density of the malaia vector, An. gambiae s.l. was higher in the resettled than the indigenous village. The overall coverage and utilization rate for at least one LLIN per household was 62.2% and 62.0% for the indigenous but 72.8% and 72.2% for the resettled village, respectively. Average prevalence of self-reported malaria episode per household in the villages were 31.1% and 41.1% for the indigenous and the resettled villages in that order. Logistic regression revealed that use of nets for other purposes, saving nets for future use and possession of radio had significant association with net ownership and utilization in the surveyed households. Indoor malaria vector and the disease prevalence tend to increase in the resettled village than the indigenous village regardless of significantly higher net ownership and utilization in the former village. Therefore, the impact of housing, insecticide resistance and feeding behavior of the target vectors need to be monitored as they might impact on protective efficacy of LLINs.

Keywords: Ethiopia, long-lasting insecticidal nets, self-reported malaria episode, resettlement