Operational research on the economics of insecticide-treated mosquito nets: lessons of experience

Towards achieving Abuja targets: identifying and addressing barriers to access and use of insecticides treated nets among the poorest populations in Kenya

Background

Ensuring that the poor and vulnerable population benefit from malaria control interventions remains a challenge for malaria endemic countries. Until recently, ownership and use of insecticides treated nets (ITNs) in most countries was low and inequitable, although coverage has increased in countries where free ITN distribution is integrated into mass vaccination campaigns. In Kenya, free ITNs were distributed to children aged below five years in 2006 through two mass campaigns. High and equitable coverage were reported after the campaigns in some districts, although national level coverage remained low, suggesting that understanding barriers to access remains important. This study was conducted to explore barriers to ownership and use of ITNs among the poorest populations before and after the mass campaigns, to identify strategies for improving coverage, and to make recommendations on how increased coverage levels can be sustained.

Methods

The study was conducted in the poorest areas of four malaria endemic districts in Kenya. Multiple data collection methods were applied including: cross-sectional surveys (n = 708 households), 24 focus group discussions and semi-structured interviews with 70 ITN suppliers.

Results

Affordability was reported as a major barrier to access but non-financial barriers were also shown to be important determinants. On the demand side key barriers to access included: mismatch between the types of ITNs supplied through interventions and community preferences; perceptions and beliefs on illness causes; physical location of suppliers and; distrust in free delivery and in the distribution agencies. Key barriers on the supply side included: distance from manufacturers; limited acceptability of ITNs provided through interventions; crowding out of the commercial sector and the price. Infrastructure, information and communication played a central role in promoting or hindering access.

Conclusions

Significant resources have been directed towards addressing affordability barriers through providing free ITNs to vulnerable groups, but the success of these interventions depends largely on the degree to which other barriers to access are addressed. Only if additional efforts are directed towards addressing non-financial barriers to access, will high coverage levels be achieved and sustained.

Transferability of economic evaluations: approaches and factors to consider when using results from one geographic area for another

BACKGROUND

Geographic transferability of economic evaluation data from one country to another has the potential to make a more efficient use of national and international evaluation resources. However, inappropriate transferability of economic data can provide misleading results and lead to an inefficient use of scarce health care resources.

OBJECTIVES

The objective of this study was to review, summarize and categorize the literature on: (i) factors affecting the geographic transferability of economic evaluation data; and (ii) approaches which have either been proposed or used for transferability.

METHODS

A systematic literature review on transferability was conducted. Electronic databases, hand searching and bibliographic searching techniques were utilized. Inclusion criteria for the review included conceptual or empirical papers with mention of factors affecting, or approaches for, transferability of economic evaluation data across geographic locations. Exclusion criteria included papers published prior to 1966, non-English language papers, pure science studies and animal studies. Three databases were involved in the primary search: Ovid MEDLINE, EMBASE, and CINAHL. In addition to the primary search, the Heath Economic Evaluation Database (OHE HEED), the NHS EED database and the EconLit databases were searched. Transferability factors were classified into major and minor categories, a classification of alternative transferability approaches was developed, and the number of empirical studies was catalogued according to this classification.

RESULTS

There is a substantial amount of literature on factors potentially affecting transferability. Based on these papers we identified 77 factors and subsequently developed a classification system which grouped these factors into five broad categories based on characteristics of the patient, the disease, the provider, the health care system and methodological conventions. Another 40 studies were identified which attempted to transfer economic evaluation data from one country to another and these were classified according to the sources for clinical efficacy, resource utilization and unit cost data.

CONCLUSIONS

There is strong evidence indicating that transferability of economic evaluation data is a difficult and complex task. Approaches which have been used for transferability suggest that, at a minimum, there is a need for country-specific substitution of practice pattern data as well as unit cost data. A limitation of this review relates to the lack of empirical studies which prevents stronger conclusions regarding which transferability factors are most important to consider and under which circumstances.

A study of malaria care provider choice in Ghana

Improved understanding of the factors that influence malaria care seeking behaviour is necessary in order to enhance the effectiveness of current malaria control strategies. This paper empirically examines the factors that affect household choice of malaria treatment options in Ghana. The treatment options considered were choice of a public provider of health care, a private provider, purchase of drugs from a drug store, or self-medication. The results indicate that treatment and time costs are significant factors affecting the choice of health care provider. Education and household size also play an important role in malaria care seeking behaviour. The demand for malaria care is inelastic with respect to costs, and the magnitudes of the elasticities suggest that malaria care is a necessity. The policy implications are addressed.

Socio-economic factors associated with the purchasing of insecticide-treated nets in Afghanistan and their implications for social marketing

Malaria is often a major health problem in war-torn countries in the tropics owing to the collapse of health services and the vulnerability of displaced populations to epidemics. Insecticide-treated nets (ITN) represent one of the few options for obtaining protection against malaria in unstable settings deficient in health infrastructure. Social marketing of subsidized ITN by a consortium of non-governmental organizations began in Afghanistan in 1993 and has continued every year since then despite regular political turmoil. Almost 350,000 nets have been sold and approximately 1.2 million people protected. In 2000 we examined the determinants of ITN purchasing among households in Nangarhar province, eastern Afghanistan, as part of an effort to increase ITN uptake. The survey was conducted using a structured questionnaire to collect data on socio-economic characteristics and malaria beliefs and practices among more than 400 net-owning and non-net-owning households. A composite socio-economic index was created using principal components analysis, and survey households were divided into socio-economic quartiles. ITN were 4.5 times more likely to be purchased by families from the richest quartile and 2.3 times more likely to be purchased from the upper-middle quartile than from the two lower quartiles. Even so, a significant minority from the lower quartiles did prioritize and buy ITN. In conflict affected countries where livelihoods are compromised, it is necessary to target subsidies at the most impoverished to make ITN affordable and to improve overall coverage.

The economic impact of malaria in Africa: a critical review of the evidence

Information on the economic burden of malaria in Africa is needed to target interventions efficiently and equitably, and to justify investment in research and control. A standard method of estimation has been to sum the direct costs of expenditure on prevention and treatment, and the indirect costs of productive labour time lost. This paper discusses the many problems in using such data to reflect the burden to society or the potential benefits from control. Studies have generally focussed on febrile illness, overestimating the burden of uncomplicated malaria, but underestimating the costs of severe illness, other debilitating manifestations, and mortality. Many use weak data to calculate indirect costs, which fail to account for seasonal variations, the difference between the average and marginal product of labour, and the ways households and firms 'cope' in response to illness episodes. Perhaps most importantly, the costs of coping mechanisms in response to the risk of disease are excluded, although they may significantly affect productive strategies and economic growth. Future work should be rooted in a sound understanding of the health burden of malaria and the organisation of economic activities, and address the impact on the productive environment, and epidemiological and socio-economic geographical variation.

Research that influences policy and practice - characteristics of operational research to improve malaria control in Mpumalanga Province, South Africa

BACKGROUND

Much communicable disease control research has had little impact on local control programme policy and practice for want of an operational component. The operational research model - the systematic search for knowledge on interventions, tools or strategies that enhance programme effectiveness - is gaining recognition as an appropriate method for addressing perplexing questions within public health programmes.

METHODS

A series of operational research studies were conducted to refine malaria diagnosis in Mpumalanga Province, South Africa between 1995 and 1999. The grounded theory approach was used with groups of experienced Masters of Public Health students in South Africa and Australia to analyse a compilation of these studies for determining positive and negative attributes of operational research that affect its ability to influence communicable disease control policy and practice.

RESULTS

The principal positive attributes of the operational research studies were high local relevance, greater ability to convince local decision-makers, relatively short lag-time before implementation of findings, and the cost-effective nature of this form of research. Potential negative features elicited included opportunities forfeited by using scarce resources to conduct research and the need to adequately train local health staff in research methodology to ensure valid results and accurate interpretation of findings.

CONCLUSIONS

Operational research effectively influenced disease control policy and practice in rural South Africa, by providing relevant answers to local questions and engaging policy-makers. This resulted in accelerated inclusion of appropriate measures into a local communicable disease control programme.

Unit costs for house spraying and bednet impregnation with residual insecticides in Colombia: a management tool for the control of vector-borne disease

A study of unit costs and cost components of two malaria-control strategies (house spraying and bednet impregnation with residual insecticides) was undertaken in 11 malaria-endemic states (departamentos) of Colombia, using data provided by control staff on self-administered questionnaires. The accuracy of the data was verified by personal visits, telephone conversations and complementary information from 10 other states. Allthe financial-cost components of the malaria-control operations carried out in the previous 6 months and the results of the control operations themselves (including the numbers of houses sprayed and numbers of bednets impregnated/day) were recorded. The information was stratified according to whether the target communities were 'near' or 'far away' from an operational base, the far-away communities being those that needed overnight stays by the control staff. The main variables analysed were unit costs/house treated, and annual cost/person protected. The results show that house spraying was generally more expensive for the health services than bednet impregnation. This is particularly the case in 'nearby' communities, where most of those at-risk live. In such communities, spraying one house was 7.2 times more expensive than impregnating one bednet. Even if only those sleeping under an impregnated net were assumed to be protected, the unit costs/person protected in a 'nearby' community were twice as high for house spraying than for bednet impregnation. In 'nearby' communities, where technicians could return to the operational base each evening, insecticides made up 80% of the total spraying costs and 42% of the costs of bednet impregnation. In 'far-away' communities, however, salaries and 'per diems' were the most important cost components, representing, respectively, 23% and 22% of the costs of spraying, and 34% plus 27% of the costs of impregnation. Insecticide wastage and non-use of discounts on insecticide prices (available through the national Ministry of Health) increased the overall costs considerably. The multiple uses of these cost calculations for district health managers are presented.

The cost of not treating bednets

For centuries, bednets have been used as a physical barrier against biting insects. Recent epidemiological investigations into their protective effects against malaria were quickly overtaken by studies focusing on the benefits of impregnating bednets with insecticide. The operational problems encountered in re-treating bednets with insecticide are often cited as an impediment to wide-scale implementation. The evidence for a protective effect of untreated nets against malaria is presented here alongside an analysis of how well untreated nets would need to work in order to compete with treated nets within a cost-effectiveness framework.