The Farmer Field School: a method for enhancing the role of rural communities in malaria control ?

The Farmer Field School (FFS) has one of the most impressive track records in participatory community approaches [15], with 2–3 million farmers graduated on the agricultural subject of Integrated Pest Management (IPM) during the past 15 years, mainly in Asia, but more recently also in Africa, the Middle East and Latin America [16]. A review of 25 impact studies indicated a range of positive outcomes of IPM Farmer Field Schools including drastic reductions in agro-pesticide use, economic benefits and empowerment effects [17]. The FFS approach evolved from the need to strengthen the ecological basis of Integrated Pest Management (IPM) to deal with the variability and complexity of agro-ecosystems whilst reducing reliance on pesticides. The ecology of opportunist insects (which include mosquitoes) is highly localized and dynamic, with populations fluctuating manyfold both spatially and temporally. Accordingly, most tropical smallholder agro-ecosystems require management decisions that are tailored to local and contemporary conditions. This implies the need to decentralize expertise to the field level by educating local people to analyse field situations and to make appropriate management decisions.

The Farmer Field School is a form of education which uses experiential learning methods to build farmers' expertise [18]. In sessions at weekly intervals during a crop cycle, a group of 15–30 neighbouring farmers meet in an open-air situation to take observations of the agro-ecosystem (Figure 1). Several sub-groups of farmers sample the populations and characteristics of harmful and beneficial organisms, plants, soil and environmental conditions. These observations are analysed and presented on newsprint for group discussion, which provides an opportunity for speculation (for example, "what if, instead of spraying, we drain the water to control planthoppers in rice"), leading to decision-making on experimental action to be evaluated in the following week. These weekly completed learning cycles result in strengthened skills and increased confidence of farmers. Several additional observations or experiments are conducted during the field school to study life cycles, insect behaviour, and plant damage. Group dynamics and communication exercises are conducted to strengthen group cohesion, maintain motivation and help participants to develop organizational skills. Group building is important in approaches such as IPM and disease vector management, which benefit from coordinated management by many farmers over a large area. Post FFS support has been given in a number of countries to facilitate the emergence of local project initiative [18].

It is noteworthy that the educational investment in agriculture can indirectly benefit health. Specifically, IPM Farmer Field School programmes located in malarious areas will inadvertently influence malaria epidemiology if income and living standards are raised (by improving people's access to health care) and if agro-pesticide use is reduced (by lowering the risk of insecticide resistance in malaria vectors). IPM programmes may be complementary to malaria control efforts. A coordinated inter-sectoral planning and implementation of activities could potentially make better use of scarce resources and synergise effects. It is proposed that integration could be taken one step further. A logical adaptation of the IPM Farmer Field School is to make the ecology and control of malaria disease implicit in the IPM curriculum, by purposely involving farmers and other interested actors in the management of malaria in their environment.

This combined strategy, labeled Integrated Pest and Vector Management (IPVM), can be expected to affect malaria disease in four different ways (Figure 2). First, as mentioned above, a reduced use of agro-pesticides, the most consistent outcome of IPM Farmer Field School programmes, will lower the risk of resistance in the vector. Second, experiential learning leads to practical knowledge about the ecology and epidemiology of malaria, which could influence personal protection measures or treatment-seeking behaviour. Third, IPM results in increased income from agriculture, due to increased yield and due to savings in pesticide expenditure [17]. An economic outcome may benefit nutrition, housing conditions and access to health services. Fourth, environmental management by farming communities is expected to suppress mosquito breeding and, consequently, to reduce the period and/or intensity of disease transmission. Critical issues in environmental management are the portion of breeding sites covered, the local landscape and possible increased fitness or survival of the vector at reduced population density. Reduction of nuisance mosquitoes (which is in itself a benefit), could affect bednet use unless this matter is taken up in the FFS curriculum.

This broad range of outcomes implies that the IPVM methodology is not necessarily restricted to situations where prospects for environmental management exist. IPVM could be targeted to address rural poverty, awareness or pesticide over-use, even in areas where environmental management is not an option.

Synergistic relationships between rice cultivation and vector management have long been known [19], which makes wetland rice a promising starting point for an integrated strategy. Wetland rice can produce large vector populations, though not necessarily of high vectorial capacity. Interruption of vector breeding in leveled fields is often technically feasible through regular drainage [20] or through appropriate management during the fallow period [21]. Considering the flight radius of anophelines, however, field-level management would need to be implemented over a sufficient area to have an effect on vector populations. This requires active participation of large numbers of farmers. In many irrigation situations, water management is insufficiently controlled by individual farmers, although this is potentially improved through the FFS and its socio-political impacts.

In epidemic-prone areas at the margins of malaria transmission, or in areas with strong seasonal malaria, a reduced period or intensity of transmission is expected to cause a temporary decline in malarial disease, because parasitaemia usually results in disease in non-immune people. In parts of Africa with stable holoendemic malaria, a reduced transmission is expected to reduce the risk of severe disease, particularly in infants and young children before they have acquired a certain level of natural immunity [22]. As far as possible, environmental management of malaria needs to be conducted alongside other locally-appropriate control interventions, under an evidence-based Integrated Vector Management (IVM) approach [6]. Ultimately, the impact of community-based activities on local transmission and morbidity of malaria needs to be assessed. This requires locally clustered field school programmes to achieve an appropriate scale, a control and local measurements of transmission and morbidity.

The IPVM Farmer Field School curriculum has recently been developed for the wetland rice ecosystem in Sri Lanka. The project, involving one of us (HvdB), built on the experience of an existing IPM project. Experiential learning exercises on the health component have been developed to complement, not replace, the existing curriculum on IPM.

The process of curriculum development was mostly in the hands of selected IPM facilitators with technical support from health resource persons. Learning objectives for the new curriculum were based on surveys, which were conducted by the facilitators to study the perceptions and knowledge of rural people about vector-borne diseases, in particular malaria. The developed learning exercises used simple and easily replicable methods, as well as locally available materials. The health component was addressed mainly in the first part of the season, when most anopheline breeding takes place. Different gender roles were noted by the facilitators, women showing most interest in the health component and men in the agricultural component. Preliminary observations in Sri Lanka suggest that farmers can be motivated and educated to play an active and competent role in vector management. Similar curricula could be included in formal school education in rural areas.

Details of the learning exercises are given in Table 1. Sampling of mosquito developmental stages and aquatic predators was incorporated within the weekly exercise of agro-ecosystem analysis. The exercise was initiated well before planting and continued as long as standing water was available in the field; post-harvest larval breeding had not been identified as an important issue. Farmers learned to recognize the larvae and adults of the three main mosquito genera, Anopheles, Culex and Aedes, using behavioural and taxonomic clues, to study mosquito-breeding habitat, and to monitor adult mosquitoes. Mosquito life cycles and mosquito predators were studied by daily observations inside transparent containers. Land leveling and alternate wet-dry irrigation were implemented in the study plots to manage mosquitoes, and farmers learned to practice source reduction, through filling, draining or manipulating water bodies in their environment. This involved planning, mapping and action by the group of participating farmers. The disease cycle of malaria, a topic unsuitable for practical learning, was addressed through a role-play, whereby farmers were assigned roles of human hosts, vector and parasite stages, and whereby the process of transmission was performed.