Integrated Vector Management

ANNE WILSON: The Global Challenge of Vector-borne Diseases and How to Control Them. In this session, we’re going to be talking about Integrated Vector Management or IVM. The aim of this session is to be able to describe the key characteristics of integrated vector management. And the objectives are to understand the key principles of integrated vector management, understand the cyclical process of integrated vector management, and to be able to give examples of nonhealth sector involvement in vector control and why this is important. Integrated Vector Management, typically called IVM, is the World Health Organisation recommended approach for control of vector-borne diseases globally.

It has a long history with release of the WHO Global Strategic Framework for IVM in 2004 and most recently in 2016 publication of a how-to guide or toolkit for IVM in sub-Saharan Africa. IVM aims to make vector control more efficient, cost effective, ecologically sound, and sustainable. It’s not simply a type of vector control but is instead the approach which should be followed for control of vector-borne diseases worldwide. It is not replaced by the WHO global vector control response from 2017 to 2030. And indeed, the new WHO strategy calls for strengthening of many of the elements which make up IVM. According to the World Health Organisation, IVM has five key characteristics. The first is that it uses an integrated approach.

This means that IVM can address several diseases using vector control tools often in combination and synergistically. It also means that we should be using both chemical and nonchemical vector control methods.

In IVM programmes, we should also be integrating vector control with use of vaccines, mass drug administration, and diagnosis and treatment.

The second key characteristic of IVM is that we should be utilising evidence-based decision making. Vector control strategies employed should be adapted to the local setting in terms of vector ecology and epidemiologic disease and should be guided by operational research, surveillance, and monitoring evaluation. Vector control tools employed should have a strong evidence base on their efficacy. Thirdly, IVM relies on collaboration within and outside the health sector. More on this later. The fourth key characteristic of IVM is that we should be utilising advocacy, social mobilisation, and legislation as well. The principles of IVM should be promoted and integrated into all policies.

Regulatory and legislative controls for public health, such as bylaws to find those with mosquito habitats on their premises, should be established or strengthened. It is essential that communities are engaged and empowered to reduce risk of vector-borne diseases in order to make the programme sustainable. And the fifth and final key characteristic is that we should really focus on capacity building with availability of infrastructure, financial, and human resources at all levels and the establishment of training causes, curricula, and career structures to train and retain staff. The WHO definition of IVM is pretty complicated. So here’s a quick reminder of the key principles of IVM. IVM can be summarised as an evidence-based, adaptive, and multisectoral approach to vector control.

This means it uses proven tools based on the local vector and disease situation, Programme should adapt what they do based on vector surveillance and monitoring evaluation, and that IVM uses tools from within and outside the health sector. I mentioned earlier the integration of tools across diseases. IVM can involve the use of multiple tools against a single disease or alternatively can involve single or multiple methods against multiple diseases. For example, long-lasting insecticidal nets can be efficacious against both malaria and lymphatic filariasis in places where lymphatic filariasis is transmitted by Anopheles gambiae. So how do you go about doing IVM? IVM can be seen as a type of adaptive management.

The first step is to conduct a thorough situation analysis, which means looking at the diseases and infections present, identifying and assessing the different vector species responsible or capable of transmission, stratifying the geographic area depending on its information, and also identifying local determinants of disease, such as community behaviours. Secondly, programmes should select Programme vector control tools in an evidence-based manner. Thirdly, programmes should get ready to implement by identifying the needs and resources required to implement the vector control Programme. Next, vector controls should be implemented. Lastly, no interventions should be implemented without appropriate monitoring and evaluation. This is really important and is often an overlooked part of vector control.

This means monitoring Programme performance continuously such as delivery of bed nets or implementation of larvaciding. Evaluation should also be conducted periodically to determine whether activities have led to the expected outcomes and impact. This means looking at entomological outcomes, for example, reductions in vector populations, as well as epidemiological outcomes, for example, reductions in morbidity and mortality.

It’s hugely important that there is strong political will behind IVM. This means it needs support from top government in order for it to be successful and sustainable. A first step is to set up an intersectoral steering committee which is responsible for making decisions on IVM and coordinating activities across sectors. This steering committee should have broad representation of different government ministries, local government and municipal authorities, community groups, the private sector, teaching and academic institutions, and nongovernmental institutions. The representatives of these institutions, particularly government ministries and local government, are responsible for advocating for IVM to be added to their respective strategic plans and for funding to be made available. When getting started with IVM, there are some really important prerequisites.

Firstly, it’s hugely important that there is strong political will behind IVM. This means it needs support from top government in order for it to be successful and sustainable. A first step is to set up an intersectoral steering committee which is responsible for making decisions on IVM and coordinating activities across sectors. This steering committee should have broad representation of different government ministries such as agriculture and finance, as well as local government and municipal authorities. Community groups should also be represented and the private sector, teaching and academic institutions, and non-governmental institutions as well.

The representatives of these institutions, particularly government ministries and local government, are responsible for advocating for IVM to be added to their respective strategic plans and for funding to be made available. The intersectoral steering committee can be replicated at provincial or state level and at local level. IVM focal persons can drive the IVM agenda. This intersectoral steering committee should commission a vector control needs assessment where the Programme outlines what activities they do currently, what resources they have available, and what potential there is to work across sectors. Tools for doing this are available from the WHO. It’s important to tailor IVM based on disease determinants.

As mentioned, one of the key elements of IVM is doing a thorough situation analysis and implementing tailored vector control on the basis of this. Vector-borne diseases are determined by several factors.

These are the vector itself, the pathogen, humans, the environment, and in some case animals, for example, where there is an intermediate host as in the case of domestic cattle and wild animals for Rhodesian Human African Trypanosomiasis. Pathogen-related factors include the availability and effectiveness of drugs and vaccines for prevention and treatment. It’s important to know what vectors are present, what their breeding sites are and behaviours, and insecticide susceptibility. Human factors include identifying where high-risk groups live and work, where they’re getting infected, and other factors such as socioeconomic status, local knowledge, attitudes, and practises towards vector-borne diseases, and access to diagnosis and treatment.

Environmental factors include local ecosystems and land use, climate patterns, and the type, distribution, and extent of immature vector development sites. When there is an animal reservoir, it is important to know the species involved and their distribution. Given the knowledge of all these factors, geographic areas can be stratified. And the approach is tailored to the specific location. IVM combines traditional health sector-led interventions, such as long-lasting insecticidal nets and indoor residual spraying, with those from the nonhealth sector. This is where the intersectoral steering committee comes into its own. Some possible interventions from outside the health sector include improved housing implemented by the Ministry of Housing, housing cooperatives, housing microfinance initiatives, and nongovernmental organisations.

Drain clearance and solid waste management can be implemented by municipal authorities, private waste management companies, and community groups. Regular drying of irrigated fields can be promoted or enforced by the Ministry of Agriculture. Education campaigns and behaviour change communication can be delivered through community groups, workplaces, schools, and the media. Provision of regular piped water to reduce or prevent water storage in and around homes is also really important as these can act as habitats for Aedes mosquitoes. IVM combines traditional health sector-led interventions, such as insecticidal bed nets and indoor residual spraying, with those from the nonhealth sector. This is where the intersectoral steering committee with its broad representation comes into its own.

Some possible interventions from outside the health sector include improved housing, which can be implemented by the Ministry of Housing, housing cooperatives, housing microfinance initiatives, and nongovernmental organisations. Drain clearance and solid waste management can be implemented by municipal authorities, private waste management companies, and community groups. Regular drying of irrigated fields can be promoted or enforced by the Ministry of Agriculture. Education campaigns and behaviour change communication can be delivered through community groups, workplaces, schools, and the media. The water authorities should be engaged to provide pipe water to reduce or prevent water storage in and around homes since these habitats can act as perfect habitats for Aedes mosquitoes.

Another idea is to engage the Department of Public Works in order to level roads, which can also act as malaria vector habitats. In summary, all vector control programmes worldwide should be following the principles of IVM. The WHO Global Vector Control Response built upon the principles of IVM and is complementary to it. It’s really important for IVM to work that we have strong political will. IVM follows a cyclical process from a situation analysis, selection of tools, implementation, and monitoring evaluation. Vector control should be implemented in a targeted fashion based on the determinants of disease and infection. And lastly, involving the nonhealth sector and communities in vector control is imperative as it can make vector control more effective and sustainable.