In Ethiopia, malaria is a leading cause of public health problem and impediment to socioeconomic development. Plasmodium falciparum and Plasmodium vivax are the two most common malaria parasites in Ethiopia, having annual percentage prevalence of 60% and 40%, respectively [1-3].
An important feature in the epidemiology of malaria in Ethiopia is the brevity of transmission season that precludes the development of immunity, favouring periodic epidemics with high mortality . In general, knowing the biology, behaviour, habitat and identification of the vector species helps to decide and implement appropriate vector control methods . Mosquitoes of the Anopheles gambiae complex are the most important malaria vectors in the world and are composed of seven sibling species namely, An. gambiae sensu stricto (s.s.), Anopheles arabiensis, Anopheles bwambae, Anopheles merus, Anopheles melas and Anopheles quadriannulatus (species A and B). However, only An. gambiae s.s. and An. arabiensis have become widely distributed and are most efficient vectors. Moreover, they are most important as far as intensified transmission of malaria is concerned [5,6]. Of the An. gambiae complex siblings, An. arabiensis and An. quadriannulatus sp.B are known to occur in Ethiopia  and malaria in Ethiopia is transmitted mainly by An. arabiensis [8,9]
Vector control is one of the measures applied to reduce malaria transmission by aiming at reducing breeding and survival of mosquito vectors. The available vector control methods are: chemical, biological, genetic, environmental management, personal protection and integrated vector management.
Although there are many vector control methods, most of them are too expensive, ecologically harmful, and environmentally unsafe or they are practically infeasible and inaccessible to be used in poor countries like Ethiopia. Moreover, insecticide resistance is now a major problem facing malaria vector control programnes in most African countries, including Ethiopia, with most important vector species, showing resistance to one or more of the insecticide classes used in vector control [4,8-10].
There is a need to have an intervention that better avoids such problems. This may include the uses of mosquito repellents which may be commercially available or locally produced by the community itself. Repellents have been used to drive away or repel insects or pests. They may be in the form of smoke, spray or aerosol, oils and body lotions. Aerosols and pump sprays are intended for skin applications and treating cloths while liquid, cream, lotion and spray products enable direct skin application. In Ethiopia, wogert (Silene macroserene), kebericho (Echinops kebericho), tinjut (Ostostegia integrifolia), and woira (Olea europaea) have been shown to have repellent effects against An. arabiensis under laboratory conditions . Plant parts are burned indoors and the smoke is believed to repel and also knock down mosquitoes. They do have limitations in that they need to be applied frequently (hourly or daily) because of their short residual effect and they might have unpleasant side effects, such as coughing because of irritations from the smoke . Therefore, it is important to know which repellent products can be relied on to provide predictable and prolonged protection from insect bites with out causing side effects on human health. So, rather than burning, repellents applied on the skin are preferable and comfortable for individual use. Moreover, insect repellents may be more economically feasible than other vector control methods and they can substitute or they can be alternatives to chemical control methods, such as space spray, which contaminate the environment and are less economically feasible . Repellents are more recommended for people staying outdoors at night for work or leisure and those working in plantations and may be at risk during daytime. Repellents are also useful in combination with LLITNs by protecting people from the bite of mosquitoes before they retire to bed.
Therefore, a trial was conducted in Sodere village to evaluate the repellent efficacy of one synthetic repellent, DEET and three plant based repellents, Mygg A, 20% neem oil and 20% chinaberry oil against An. arabiensis. This research project reported the results obtained from the trial.