Consolidating tactical planning and implementation frameworks for integrated vector management in Uganda

While various global strategies have been developed to combat VBDs with renewed emphasis on vector control, malaria still remain the major cause of morbidity and mortality in Uganda [8]. The VCNA revealed several key factors that undermine the effectiveness of vector control in the country: inadequate capacity for evidence-based decision-making to guide vector control strategies at national, regional, district, and community levels, thereby resulting in sub-optimal choice or improper timing of interventions and subsequent waste of valuable resources; vector control efforts focus on a single disease and are not fully integrated into health systems, raising concern about their sustainability; the patterns of most of the VBDs, including malaria, are affected by climate change, environmental degradation and urbanization, pointing to the need for an adaptive management approach to vector control based on local evidence; other sectors such as agriculture, industrial works and construction including communities are often not well informed and involved in vector control, resulting in limited awareness of the consequences of their actions on the incidence of VBDs; long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are threatened by the development of resistance and could undermine effective vector control efforts [9]. The Stockholm Convention on Persistent Organic Pollutants (POPs) [13] and World Health Assembly resolution WHA50.13 [14] call on countries to design sustainable strategies for vector control. These opportunities, coupled with the presence of arboviral diseases also transmitted by mosquitoes, substantiated the need for an IVM approach to vector control in Uganda and the development of guidelines that apply, in principle, to all VBDs but focus specifically on malaria control in the country. The IVM strategic guideline would require regular adaptation to changes in local eco-epidemiological or socio-economic conditions.

Uganda is located along the eastern African Rift Valley within the Nile basin. It borders Kenya in the east, South Sudan in the north, the Democratic Republic of the Congo in the west, Rwanda in the southwest, and Tanzania in the south. Its topography varies, ranging from high altitude areas, including the Rwenzori Mountains (5100 m) to the low-lying Sudanese Plain in the north. The country has a tropical climate with mean annual temperatures of 16 °C in the southwest; 25 °C in the centre, east, and northwest; and close to 30 °C in the northeast with two peaks of rainfall from March to May and from September to December each year. Uganda has an area of about 241,039 sq km divided into 112 decentralized districts. Service delivery is the responsibility of the districts and their lower local governments. The estimated population of Uganda is 36.6 million people. The proportion of urban area dwellers has increased from 6.6 % in 1969 to 15.6 % in 2011 [15].

Uganda’s equatorial temperature, rainfall and relative humidity provide a conducive environment for malaria and other VBD vectors to thrive (Table 1). However, as malaria is the pathfinder for IVM in Uganda, VBDs targeted initially are those that are amenable to malaria vector control interventions. These include malaria, lymphatic filariasis, plague, visceral leishmaniasis, sleeping sickness, trachoma and arboviruses. Uganda has the third highest number of annual deaths from malaria in Africa and the highest reported malaria transmission intensities in the world [16]. Anopheles gambiae s.s., Anopheles arabiensis and Anopheles funestus are the main malaria vectors. A. gambiae s.s. is the dominant vector species in most locations. While these vectors coexist, effective IRS and LLIN interventions have changed their distribution and composition profile in Uganda. Reduced prevalence of An. funestus and An. gambiae s.s. and a dominance of An. arabiensis has been reported from IRS districts [17]. Secondary vectors include Anopheles nili, Anopheles moucheti, Anopheles obscurus and Anopheles bwambae [18]. All the four species of malaria parasites exist in Uganda: Plasmodium falciparum (95 %), Plasmodium malariae (2 %), Plasmodium vivax (2 %), and Plasmodium ovale (1 %).The whole population of Uganda is at risk of malaria [19]. Over 90 % of the population resides in areas of high and stable malaria transmission with the remainder in low and unstable malaria transmission areas [8].

The threat for emerging and re-emerging vector borne diseases i.e. dengue, chikungunya and lymphatic filariasis is increasing in East Africa. The VCNA revealed the presence of multiple VBDs with divergent endemicities and spatial distribution in Uganda, including: Schistosomiasis vectored by Bolinus and Biomphalaria spp. snails; dengue fever primarily transmitted by Aedes aegypti and Aedes albopictus; human African trypanosomiasis vectored by Glossina fuscipes, Glossina tachinoides, Glossina pallidipes and Glossina morsitans species of tsetse flies; Leishmaniasis (kala-azar) vectored by Phlebotomus orientalis, Phlebotomus martini and Phlebotomus celiae species of Sand flies; Onchocerciasis (River Blindness) vectored by Simulium damnosum black flies; lymphatic filariasis transmitted by A. gambiae, An. arabiensis and An. funestu and Culex quinquefasciatus; chikungunya and zika vectored by Ae. albopictus and Aedes aegypti; Trachoma vectored by Musica sorbens bazaar flies; plague vectored by Xenopsilla spp. Rat fleas; Tungiasis transmitted by Xenopsilla spp. Jigger fleas and Rift valley fever transmitted by Aedes spp. mosquitoes. Meanwhile, malaria targeting interventions such as IRS and LLINS also have a significant effect of on other vectors of VBDs i.e. dengue, chikungunya, zika, lymphatic filariasis, yellow fever and leishmaniasis.

The large communal-scaleuse of LLINs and IRS, supported by intensive social mobilization and behaviour change communication (BCC), are key interventions to prevent malaria and other VBDs in Uganda. The country has adopted a policy of universal coverage (one net per two people) with LLINs to protect all people from malaria and other VBDs with over 21 million nets distributed via mass campaigns. Since 2009, two spray rounds per year have been conducted in ten districts covering over 500,000 structures, achieving >90 % coverage of targeted structures and protecting over 2.6 million representing >90 % of the targeted population. In the northern and eastern regions with holo-endemic malaria transmission, LLINs and IRS are combined for the same households [19]. While there are currently no meaningful larval source management (LSM) activities at programme level, the MoH plans to implement LSM in the context of IVM in urban or peri-urban sites and arid areas of Uganda. Live-bait technology, application of insecticides on domesticated animals, especially cattle to control tick borne diseases is practiced by local communities in Greater Mbarara district. Community sensitization on the benefits of this approach to controlling several VBDs including sleeping sickness, malaria, lymphatic filariasis, and trachoma, and the expansion of these efforts into other cattle-keeping communities is required. Tsetse traps and screens are used in tsetse-infested areas such as eastern and northern Uganda and can also be used around zero-grazed cattle, to help reduce domestic animal nuisance pests, including stomoxys and tabanid flies, and to some extent malaria vectors. These devices also help reduce eye-seeking flies, thereby helping to control trachoma [20].

In Uganda major challenges to malaria control include very high malaria transmission intensity, low coverage of proven malaria control interventions, inadequate health care resources, a weak health system, inadequate understanding of malaria epidemiology and the impact of control interventions [16]. There has been a growing problem of insecticide resistance in disease vectors to organochloride, dichloro-diphenyl-trichloroethane (DDT), pyrethroids and to a lesser extent carbamates, particularly in An. gambiae s.l. and An. funestus [21, 22]. Integrated management of malaria vectors remains an underdeveloped component of malaria control policy in Uganda [23]. Most development partners have neglected health system strengthening [24]. Therefore, concerted efforts and strong political commitment that translates into adequate financial allocation for vector control, including focused research and inter-country cooperation and exchange to share best practices are urgently needed to radically scale up cost-effective interventions. Further challenges include inadequate social mobilization and sensitization of target communities due to limited resources for requisite activities. Integrated control would require strengthening of research, including studies of the efficacy and cost-effectiveness of integrated management of VBDs, knowledge, attitude and practice, community meetings, and development of and harmonization of information, education and communication (IEC) messages and their effective delivery of materials [25].

The current approaches to disease vector control in Uganda work in near isolation from each other, despite the existence of opportunities for optimal control and management of two or more VBDs in some districts [20]. To the extent possible, the available vector control tools need to be integrated in Uganda by adopting and implementing the IVM strategy. In 2013, an IVM guideline was drafted but focused on malaria and lacked inherent IVM characteristics and components. In pursuit of integrated VBD control, the National Malaria Reduction Strategic Plan (2014–2020) incorporating an IVM approach for vector control was developed and necessitated the updating of the IVM guideline [8]. An IVM strategy takes into account the available health infrastructure and resources, employs a multi-disease approach, and integrates all available and effective interventions, whether chemical, biological or environmental, involves other sectors and communities, and aims to strengthen vector control management systems [1]. IVM characteristic features include: selection of methods based on knowledge of local vector biology, disease transmission and morbidity; utilization of a range of interventions, often in combination and synergistically; collaboration within the health sector, researchers and with other public and private sectors that have an impact on vector breeding; engagement with local communities and other stakeholders; a public health regulatory and legislative framework; rational use of insecticides; and, good management practices [1].

Introduction and implementation of IVM requires a comprehensive situation analysis, and an in-depth assessment of challenges and specific vector management needs. Prior to developing an IVM strategy, a VCNA was conducted to assess existing gaps in policies, strategies, legislation, and capacity for the implementation of vector control in the context of IVM.A modified World Health Organization VCNA tool [7] was used to collect data from key informants from the NMCP, 17 districts and institutions that included the Vector Control Division (VCD), Uganda National Bureau of Statistics, Uganda Revenue Authority, National Environmental Management Authority, National Drug Authority, and Agricultural Chemical Board of the Ministry of Agriculture, Animal Industry and Fisheries. The findings of the VCNA established that there is goodwill by both government and international organizations to support IRS and LLINs, which provide a platform for resource mobilization. While implementation of LSM is rudimentary, there is local capacity to effectively implement IRS and LLINs using a partnership model that creates room for sustainability of the IVM interventions. To manage insecticide resistance, carbamates (bendiocarb) or organophosphate (pirimiphos-methyl CS) are used for IRS [26]. The Agricultural Chemicals (Control) Act, 2006 exists with attendant regulations and guidelines to handle all agricultural chemicals along the value chain [9]. However, vector control in Uganda has been characterized by many constraints. Table 2 presents the synopsis of key challenges/issues and recommendations for improving vector-borne disease control in Uganda.

In 2014, Uganda developed the IVM strategic guideline to provide a common operational framework for all vector control stakeholders for planning and implementing VBD control according to IVM characteristics and principles [20]. The guideline seeks to reorient vector control interventions in the context of emerging insecticide resistance, the need for inter-sectoral collaboration and targeted evidence-based vector control. The development of the guideline was all-inclusive and participatory, involving all key stakeholders, including civil society, academia/research, malaria development partners, and the private corporate sector. The document will be regularly adapted to changes in local eco-epidemiological or socio-economic conditions. The selection criteria for malaria vector control methods include effectiveness, affordability, safety, sustainability, risk for resistance, community acceptance, etc. (Tables 3, 4).

The mechanisms for implementation of the IVM strategic guidelines will be a joint effort by all partners and stakeholders at all levels of society through the public health system (Table 5). The MoH via the NMCP and VCD will coordinate efforts to control malaria and other VBDs using the platform of Interagency Coordination Committee for Malaria (ICCM), which is chaired by the MoH. For effective inter-sectoral collaboration, an inter-sectoral steering committee on IVM will function as an inter-ministerial governing body with a responsibility to facilitate harmonization of policies and institutional arrangements and to provide strategic direction and coordination for research and implementation of IVM. A nominated focal person for IVM will coordinate and manage networking among national partners and ensure implementation of the recommendations of the Committee.