Financial and economic costs of healthcare associated infections in Africa.

BACKGROUND: Healthcare associated infections (HAI) remain a global health challenge and have elevated rates in Sub-Saharan Africa. HAIs impact patients and their families by causing illness, prolonged hospital stay, potential disability, excess costs and sometimes death. The costs of HAI are increasing due to spreading antimicrobial resistance. A major risk factor for HAIs is lack of water, sanitation, and hygiene (WASH), environmental cleaning and healthcare waste management. In Sub-Saharan Africa these services are lacking in at least 50% of healthcare facilities. AIM: This study estimated the costs associated with HAIs at national level in fourteen countries in Sub-Saharan Africa. METHODS: Economic methodologies were employed to estimate the medical costs, productivity losses and value of premature death from HAIs, drawing on national statistics and published studies to populate the economic model. RESULTS: In 2022, the number of HAIs was estimated at 4.8 million, resulting in 500,000 deaths. Health-related economic losses amounted to US$13 billion per year, equivalent to 1.14% of combined GDP and US$15.7 per capita. Healthcare costs were US$500 per HAI and represented 5.6% of total health expenditure. The costs of providing basic WASH were US$0.91 per capita, which, if they reduced HAIs by 50%, resulted in benefit-cost ratios of 1.6 (financial health care savings only) and 8.6 (including all economic benefits). CONCLUSION: HAIs have a major health and economic burden on African societies, and a significant share can be prevented. It is critical that health policy makers and practitioners dedicate policy space, resources, and training to address HAIs.

Estimating the cost of achieving basic water, sanitation, hygiene, and waste management services in public health-care facilities in the 46 UN designated least-developed countries: a modelling study.

BACKGROUND: An alarming number of public health-care facilities in low-income and middle-income countries lack basic water, sanitation, hygiene (WASH), and waste management services. This study estimates the costs of achieving full coverage of basic WASH and waste services in existing public health facilities in the 46 UN designated least-developed countries (LDCs). METHODS: In this modelling study, in-need facilities were quantified by combining published counts of public facilities with estimated basic WASH and waste service coverage. Country-specific per-facility capital and recurrent costs to deliver basic services were collected via survey of country WASH experts and officials between Sept 24 and Dec 24, 2020. Baseline cost estimates were modelled and discounted by 5% per year. Key assumptions were adjusted to produce lower and upper estimates, including adjusting the discount rate to 8% and 3% per year, respectively. FINDINGS: An estimated US$6·5 billion to $9·6 billion from 2021 to 2030 is needed to achieve full coverage of basic WASH and waste services in public health facilities in LDCs. Capital costs are $2·9 billion to $4·8 billion and recurrent costs are $3·6 billion to $4·8 billion over this time period. A mean of $0·24-0·40 per capita in capital investment is needed each year, and annual operations and maintenance costs are expected to increase from $0·10 in 2021 to $0·39-0·60 in 2030. Waste management accounts for the greatest share of costs, requiring $3·7 billion (46·6% of the total) in the baseline estimates, followed by $1·8 billion (23·1%) for sanitation, $1·5 billion (19·5%) for water, and $845 million (10·7%) for hygiene. Needs are greatest for non-hospital facilities ($7·4 billion [94%] of $7·9 billion) and for facilities in rural areas ($5·3 billion [68%]). INTERPRETATION: Investment will need to increase to reach full coverage of basic WASH and waste services in public health facilities. Financial needs are modest compared with current overall health and WASH spending, and better service coverage will yield substantial health benefits. To sustain services and prevent degradation and early replacement, countries will need to routinely budget for operations and maintenance of WASH and waste management assets. FUNDING: WHO (including underlying grants from the governments of Japan, the Netherlands, and the UK), World Bank (including an underlying grant from the Global Water Security and Sanitation Partnership), and UNICEF. TRANSLATIONS: For the Arabic, French and Portuguese translations of the abstract see Supplementary Materials section.

Costs of hand hygiene for all in household settings: estimating the price tag for the 46 least developed countries.

INTRODUCTION: Domestic hand hygiene could prevent over 500 000 attributable deaths per year, but 6 in 10 people in least developed countries (LDCs) do not have a handwashing facility (HWF) with soap and water available at home. We estimated the economic costs of universal access to basic hand hygiene services in household settings in 46 LDCs. METHODS: Our model combines quantities of households with no HWF and prices of promotion campaigns, HWFs, soap and water. For quantities, we used estimates from the WHO/UNICEF Joint Monitoring Programme. For prices, we collated data from recent impact evaluations and electronic searches. Accounting for inflation and purchasing power, we calculated costs over 2021-2030, and estimated total cost probabilistically using Monte Carlo simulation. RESULTS: An estimated US$12.2-US$15.3 billion over 10 years is needed for universal hand hygiene in household settings in 46 LDCs. The average annual cost of hand hygiene promotion is US$334 million (24% of annual total), with a further US$233 million for 'top-up' promotion (17%). Together, these promotion costs represent US$0.47 annually per head of LDC population. The annual cost of HWFs, a purpose-built drum with tap and stand, is US$174 million (13%). The annual cost of soap is US$497 million (36%) and water US$127 million (9%). CONCLUSION: The annual cost of behavioural change promotion to those with no HWF represents 4.7% of median government health expenditure in LDCs, and 1% of their annual aid receipts. These costs could be covered by mobilising resources from across government and partners, and could be reduced by harnessing economies of scale and integrating hand hygiene with other behavioural change campaigns where appropriate. Innovation is required to make soap more affordable and available for the poorest households.

COVID-19 water, sanitation, and hygiene response: Review of measures and initiatives adopted by governments, regulators, utilities, and other stakeholders in 84 countries.

The COVID-19 pandemic has shone a light on handwashing as an inexpensive, widely applicable response measure. In consequence, most governments have taken action to promote access to water and sanitation services for all. This paper documents an overview of initiatives and interventions that countries have implemented during the first months of the COVID-19 response. Initiatives have been identified across 84 countries worldwide, and categorized into those that aimed at securing water, sanitation, and hygiene (WASH) for all, and those that sought to provide technical and financial support to service providers. The pandemic has not hit countries in the same way. Accordingly, results show disparities in the response between and within regions, with the level of activity found in the countries varying largely in terms of ambition and scope. Hygiene promotion and infection prevention and control (IPC) has been widely adopted - at least one response measure found in 94% of mapped countries -, although not always matched in ambition with the assured availability of soap, water, and handwashing facilities. Support to vulnerable households to promote basic access to WASH services at scale was weak (38% of countries) or implemented locally (25%), and requiring additional focus, particularly in rural areas and small towns. In addition, parallel support needs to be extended to service providers or to households themselves in the form of cash transfers, in order to ensure the financial viability and the continuity of services. All lessons learned distilled from the pandemic should help strengthen the enabling environment for more resilient services in future emergencies. Areas for focus could include developing specific pandemic response strategies and plans; strengthening coordination; and establishing emergency financial support mechanisms for water operators, for example. Overall, findings presented herein contribute to enhance current and future pandemics prevention, mitigation, and recovery.

Universal health coverage and intersectoral action for health: key messages from Disease Control Priorities, 3rd edition.

The World Bank is publishing nine volumes of Disease Control Priorities, 3rd edition (DCP3) between 2015 and 2018. Volume 9, Improving Health and Reducing Poverty, summarises the main messages from all the volumes and contains cross-cutting analyses. This Review draws on all nine volumes to convey conclusions. The analysis in DCP3 is built around 21 essential packages that were developed in the nine volumes. Each essential package addresses the concerns of a major professional community (eg, child health or surgery) and contains a mix of intersectoral policies and health-sector interventions. 71 intersectoral prevention policies were identified in total, 29 of which are priorities for early introduction. Interventions within the health sector were grouped onto five platforms (population based, community level, health centre, first-level hospital, and referral hospital). DCP3 defines a model concept of essential universal health coverage (EUHC) with 218 interventions that provides a starting point for country-specific analysis of priorities. Assuming steady-state implementation by 2030, EUHC in lower-middle-income countries would reduce premature deaths by an estimated 4·2 million per year. Estimated total costs prove substantial: about 9·1% of (current) gross national income (GNI) in low-income countries and 5·2% of GNI in lower-middle-income countries. Financing provision of continuing intervention against chronic conditions accounts for about half of estimated incremental costs. For lower-middle-income countries, the mortality reduction from implementing the EUHC can only reach about half the mortality reduction in non-communicable diseases called for by the Sustainable Development Goals. Full achievement will require increased investment or sustained intersectoral action, and actions by finance ministries to tax smoking and polluting emissions and to reduce or eliminate (often large) subsidies on fossil fuels appear of central importance. DCP3 is intended to be a model starting point for analyses at the country level, but country-specific cost structures, epidemiological needs, and national priorities will generally lead to definitions of EUHC that differ from country to country and from the model in this Review. DCP3 is particularly relevant as achievement of EUHC relies increasingly on greater domestic finance, with global developmental assistance in health focusing more on global public goods. In addition to assessing effects on mortality, DCP3 looked at outcomes of EUHC not encompassed by the disability-adjusted life-year metric and related cost-effectiveness analyses. The other objectives included financial protection (potentially better provided upstream by keeping people out of the hospital rather than downstream by paying their hospital bills for them), stillbirths averted, palliative care, contraception, and child physical and intellectual growth. The first 1000 days after conception are highly important for child development, but the next 7000 days are likewise important and often neglected.

The Knowledge Base for Achieving the Sustainable Development Goal Targets on Water Supply, Sanitation and Hygiene.

Safe drinking water, sanitation, and hygiene (WASH) are fundamental to an improved standard of living. Globally, 91% of households used improved drinking water sources in 2015, while for improved sanitation it is 68%. Wealth disparities are stark, with rural populations, slum dwellers and marginalized groups lagging significantly behind. Service coverage is significantly lower when considering the new water and sanitation targets under the sustainable development goals (SDGs) which aspire to a higher standard of 'safely managed' water and sanitation. Lack of access to WASH can have an economic impact as much as 7% of Gross Domestic Product, not including the social and environmental consequences. Research points to significant health and socio-economic consequences of poor nutritional status, child growth and school performance caused by inadequate WASH. Groundwater over-extraction and pollution of surface water bodies have serious impacts on water resource availability and biodiversity, while climate change exacerbates the health risks of water insecurity. A significant literature documents the beneficial impacts of WASH interventions, and a growing number of impact evaluation studies assess how interventions are optimally financed, implemented and sustained. Many innovations in behavior change and service delivery offer potential for scaling up services to meet the SDGs.

Economic evidence on the health impacts of climate change in europe.

BACKGROUND: In responding to the health impacts of climate change, economic evidence and tools inform decision makers of the efficiency of alternative health policies and interventions. In a time when sweeping budget cuts are affecting all tiers of government, economic evidence on health protection from climate change spending enables comparison with other public spending. METHODS: The review included 53 countries of the World Health Organization (WHO) European Region. Literature was obtained using a Medline and Internet search of key terms in published reports and peer-reviewed literature, and from institutions working on health and climate change. Articles were included if they provided economic estimation of the health impacts of climate change or adaptation measures to protect health from climate change in the WHO European Region. Economic studies are classified under health impact cost, health adaptation cost, and health economic evaluation (comparing both costs and impacts). RESULTS: A total of 40 relevant studies from Europe were identified, covering the health damage or adaptation costs related to the health effects of climate change and response measures to climate-sensitive diseases. No economic evaluation studies were identified of response measures specific to the impacts of climate change. Existing studies vary in terms of the economic outcomes measured and the methods for evaluation of health benefits. The lack of robust health impact data underlying economic studies significantly affects the availability and precision of economic studies. CONCLUSIONS: Economic evidence in European countries on the costs of and response to climate-sensitive diseases is extremely limited and fragmented. Further studies are urgently needed that examine health impacts and the costs and efficiency of alternative responses to climate-sensitive health conditions, in particular extreme weather events (other than heat) and potential emerging diseases and other conditions threatening Europe.

Global costs and benefits of reaching universal coverage of sanitation and drinking-water supply.

Economic evidence on the cost and benefits of sanitation and drinking-water supply supports higher allocation of resources and selection of efficient and affordable interventions. The study aim is to estimate global and regional costs and benefits of sanitation and drinking-water supply interventions to meet the Millennium Development Goal (MDG) target in 2015, as well as to attain universal coverage. Input data on costs and benefits from reviewed literature were combined in an economic model to estimate the costs and benefits, and benefit-cost ratios (BCRs). Benefits included health and access time savings. Global BCRs (Dollar return per Dollar invested) were 5.5 for sanitation, 2.0 for water supply and 4.3 for combined sanitation and water supply. Globally, the costs of universal access amount to US$ 35 billion per year for sanitation and US$ 17.5 billion for drinking-water, over the 5-year period 2010-2015 (billion defined as 10(9) here and throughout). The regions accounting for the major share of costs and benefits are South Asia, East Asia and sub-Saharan Africa. Improved sanitation and drinking-water supply deliver significant economic returns to society, especially sanitation. Economic evidence should further feed into advocacy efforts to raise funding from governments, households and the private sector.

Human resources for health care delivery in Tanzania: a multifaceted problem.

BACKGROUND: Recent years have seen an unprecedented increase in funds for procurement of health commodities in developing countries. A major challenge now is the efficient delivery of commodities and services to improve population health. With this in mind, we documented staffing levels and productivity in peripheral health facilities in southern Tanzania. METHOD: A health facility survey was conducted to collect data on staff employed, their main tasks, availability on the day of the survey, reasons for absenteeism, and experience of supervisory visits from District Health Teams. In-depth interview with health workers was done to explore their perception of work load. A time and motion study of nurses in the Reproductive and Child Health (RCH) clinics documented their time use by task. RESULTS: We found that only 14% (122/854) of the recommended number of nurses and 20% (90/441) of the clinical staff had been employed at the facilities. Furthermore, 44% of clinical staff was not available on the day of the survey. Various reasons were given for this. Amongst the clinical staff, 38% were absent because of attendance to seminar sessions, 8% because of long-training, 25% were on official travel and 20% were on leave. RCH clinic nurses were present for 7 hours a day, but only worked productively for 57% of time present at facility. Almost two-third of facilities had received less than 3 visits from district health teams during the 6 months preceding the survey. CONCLUSION: This study documented inadequate staffing of health facilities, a high degree of absenteeism, low productivity of the staff who were present and inadequate supervision in peripheral Tanzanian health facilities. The implications of these findings are discussed in the context of decentralized health care in Tanzania.

Cost-effectiveness of intermittent preventive treatment of malaria in infants (IPTi) for averting anaemia in Gabon: a comparison between intention to treat and according to protocol analyses.

BACKGROUND: In Gabon, the impact of intermittent preventive treatment of malaria in infants (IPTi) was not statistically significant on malaria reduction, but the impact on moderate anaemia was, with some differences between the intention to treat (ITT) and the according to protocol (ATP) trial analyses. Specifically, ATP was statistically significant, while ITT analysis was borderline. The main reason for the difference between ITT and ATP populations was migration. METHODS: This study estimates the cost-effectiveness of IPTi on the reduction of anaemia in Gabon, comparing results of the ITT and the ATP clinical trial analyses. Threshold analysis was conducted to identify when the intervention costs and protective efficacy of IPTi for the ATP cohort equalled the ITT cost-effectiveness ratio. RESULTS: Based on IPTi intervention costs, the cost per episode of moderate anaemia averted was US$12.88 (CI 95% 4.19, 30.48) using the ITT analysis and US$11.30 (CI 95% 4.56, 26.66) using the ATP analysis. In order for the ATP results to equal the cost-effectiveness of ITT, total ATP intervention costs should rise from 118.38 to 134 US$ ATP or the protective efficacy should fall from 27% to 18.1%. The uncertainty surrounding the cost-effectiveness ratio using ITT trial results was higher than using ATP results. CONCLUSIONS: Migration implies great challenges in the organization of health interventions that require repeat visits in Gabon. This was apparent in the study as the cost-effectiveness of IPTp-SP worsened when drop out from the prevention was taken into account. Despite such challenges, IPTi was both inexpensive and efficacious in averting cases of moderate anaemia in infants.

The economics of health and climate change: key evidence for decision making.

BACKGROUND: In responding to the health challenges of climate change, those responsible for health policies and resource allocations need to know the resource consequences of their decisions. This article examines the availability and strength of economic evidence for policy makers to draw on in making health policy decisions. METHODS: Relevant literature was obtained using a Medline and INTERNET search of key terms and institutions working in health and climate change. Eighteen available economic studies are presented under three categories of economic evidence: health damage cost, health adaptation cost and health economic evaluation. RESULTS: In economic studies valuing the predicted increased mortality from climate change, the health damages represent an important fraction of overall economic losses. Similarly, when considering broader health protection measures beyond the health sector (e.g. agriculture, water supply) health considerations are central. Global adaptation cost studies carried out so far indicate health sector costs of roughly US$2-5 billion annually (mid-estimates). However, these costs are expected to be an underestimate of the true costs, due to omitted health impacts, omitted economic impacts, and the costs of health actions in other sectors. No published studies compare the costs and benefits of specific health interventions to protect health from climate change. CONCLUSIONS: More economic studies are needed examining the costs and benefits of adaptation measures to inform policy making. There is an urgent need for climate change-specific health economic guidelines to ensure robust methods are used, giving comparable results. Broader advocacy and focused training of decision makers is needed to increase the uptake of economic evidence in decision making. Until further climate change-specific economic studies have been conducted, decision makers should selectively draw on published studies of the costs and benefits of environmental health interventions.

The cost-effectiveness of intermittent preventive treatment for malaria in infants in Sub-Saharan Africa.

BACKGROUND: Intermittent preventive treatment in infants (IPTi) has been shown to decrease clinical malaria by approximately 30% in the first year of life and is a promising malaria control strategy for Sub-Saharan Africa which can be delivered alongside the Expanded Programme on Immunisation (EPI). To date, there have been limited data on the cost-effectiveness of this strategy using sulfadoxine pyrimethamine (SP) and no published data on cost-effectiveness using other antimalarials. METHODS: We analysed data from 5 countries in sub-Saharan Africa using a total of 5 different IPTi drug regimens; SP, mefloquine (MQ), 3 days of chlorproguanil-dapsone (CD), SP plus 3 days of artesunate (SP-AS3) and 3 days of amodiaquine-artesunate (AQ3-AS3).The cost per malaria episode averted and cost per Disability-Adjusted Life-Year (DALY) averted were modeled using both trial specific protective efficacy (PE) for all IPTi drugs and a pooled PE for IPTi with SP, malaria incidence, an estimated malaria case fatality rate of 1.57%, IPTi delivery costs and country specific provider and household malaria treatment costs. FINDINGS: In sites where IPTi had a significant effect on reducing malaria, the cost per episode averted for IPTi-SP was very low, USD 1.36-4.03 based on trial specific data and USD 0.68-2.27 based on the pooled analysis. For IPTi using alternative antimalarials, the lowest cost per case averted was for AQ3-AS3 in western Kenya (USD 4.62) and the highest was for MQ in Korowge, Tanzania (USD 18.56). Where efficacious, based only on intervention costs, IPTi was shown to be cost effective in all the sites and highly cost-effective in all but one of the sites, ranging from USD 2.90 (Ifakara, Tanzania with SP) to USD 39.63 (Korogwe, Tanzania with MQ) per DALY averted. In addition, IPTi reduced health system costs and showed significant savings to households from malaria cases averted. A threshold analysis showed that there is room for the IPTi-efficacy to fall and still remain highly cost effective in all sites where IPTi had a statistically significant effect on clinical malaria. CONCLUSIONS: IPTi delivered alongside the EPI is a highly cost effective intervention against clinical malaria with a range of drugs in a range of malaria transmission settings. Where IPTi did not have a statistically significant impact on malaria, generally in low transmission sites, it was not cost effective.

Cost-effectiveness of malaria intermittent preventive treatment in infants (IPTi) in Mozambique and the United Republic of Tanzania.

OBJECTIVE: To estimate the cost-effectiveness of malaria intermittent preventive treatment in infants (IPTi) using sulfadoxine-pyrimethamine (SP). METHODS: In two previous IPTi trials in Ifakara (United Republic of Tanzania) and Manhiça (Mozambique), SP was administered three times to infants before 9 months of age through the Expanded Programme on Immunization. Based on the efficacy results of the intervention and on malaria incidence in the target population, an estimate was made of the number of clinical malaria episodes prevented. This number and an assumed case-fatality rate of 1.57% were used, in turn, to estimate the number of disability-adjusted life years (DALY) averted and the number of deaths averted. The cost of the intervention, including start-up and recurrent costs, was then assessed on the basis of these figures. FINDINGS: The cost per clinical episode of malaria averted was US$ 1.57 (range: US$ 0.8-4.0) in Ifakara and US$ 4.73 (range: US$ 1.7-30.3) in Manhiça; the cost per DALY averted was US$ 3.7 (range: US$ 1.6-12.2) in Ifakara and US$ 11.2 (range: US$ 3.6-92.0) in Manhiça; and the cost per death averted was US$ 100.2 (range: US$ 43.0-330.9) in Ifakara and US$ 301.1 (range: US$ 95.6-2498.4) in Manhiça. CONCLUSION: From the health system and societal perspectives, IPTi with SP is expected to produce health improvements in a cost-effective way. From an economic perspective, it offers good value for money for public health programmes.

From strategy development to routine implementation: the cost of Intermittent Preventive Treatment in Infants for malaria control.

BACKGROUND: Achieving the Millennium Development Goals for health requires a massive scaling-up of interventions in Sub Saharan Africa. Intermittent Preventive Treatment in infants (IPTi) is a promising new tool for malaria control. Although efficacy information is available for many interventions, there is a dearth of data on the resources required for scaling up of health interventions. METHOD: We worked in partnership with the Ministry of Health and Social Welfare (MoHSW) to develop an IPTi strategy that could be implemented and managed by routine health services. We tracked health system and other costs of (1) developing the strategy and (2) maintaining routine implementation of the strategy in five districts in southern Tanzania. Financial costs were extracted and summarized from a costing template and semi-structured interviews were conducted with key informants to record time and resources spent on IPTi activities. RESULTS: The estimated financial cost to start-up and run IPTi in the whole of Tanzania in 2005 was US$1,486,284. Start-up costs of US$36,363 were incurred at the national level, mainly on the development of Behaviour Change Communication (BCC) materials, stakeholders' meetings and other consultations. The annual running cost at national level for intervention management and monitoring and drug purchase was estimated at US$459,096. Start-up costs at the district level were US$7,885 per district, mainly expenditure on training. Annual running costs were US$170 per district, mainly for printing of BCC materials. There was no incremental financial expenditure needed to deliver the intervention in health facilities as supplies were delivered alongside routine vaccinations and available health workers performed the activities without working overtime. The economic cost was estimated at 23 US cents per IPTi dose delivered. CONCLUSION: The costs presented here show the order of magnitude of expenditures needed to initiate and to implement IPTi at national scale in settings with high Expanded Programme on Immunization (EPI) coverage. The IPTi intervention appears to be affordable even within the budget constraints of Ministries of Health of most sub-Saharan African countries.

Global costs of attaining the Millennium Development Goal for water supply and sanitation.

OBJECTIVE: Target 10 of the Millennium Development Goals (MDGs) is to "halve by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation". Because of its impacts on a range of diseases, it is a health-related MDG target. This study presents cost estimates of attaining MDG target 10. METHODS: We estimate the population to be covered to attain the MDG target using data on household use of improved water and sanitation for 1990 and 2004, and taking into account population growth. We assume this estimate is achieved in equal annual increments from the base year, 2005, until 2014. Costs per capita for investment and recurrent costs are applied. Country data is aggregated to 11 WHO developing country subregions and globally. FINDINGS: Estimated spending required in developing countries on new coverage to meet the MDG target is US$ 42 billion for water and US$ 142 billion for sanitation, a combined annual equivalent of US$ 18 billion. The cost of maintaining existing services totals an additional US$ 322 billion for water supply and US $216 billion for sanitation, a combined annual equivalent of US$ 54 billion. Spending for new coverage is largely rural (64%), while for maintaining existing coverage it is largely urban (73%). Additional programme costs, incurred administratively outside the point of delivery of interventions, of between 10% and 30% are required for effective implementation. CONCLUSION: In assessing financing requirements, estimates of cost should include the operation, maintenance and replacement of existing coverage as well as new services and programme costs. Country-level costing studies are needed to guide sector financing.

Economic evaluation of environmental health interventions to support decision making.

Environmental burden of disease represents one quarter of overall disease burden, hence necessitating greater attention from decision makers both inside and outside the health sector. Economic evaluation techniques such as cost-effectiveness analysis and cost-benefit analysis provide key information to health decision makers on the efficiency of environmental health interventions, assisting them in choosing interventions which give the greatest social return on limited public budgets and private resources. The aim of this article is to review economic evaluation studies in three environmental health areas-water, sanitation, hygiene (WSH), vector control, and air pollution-and to critically examine the policy relevance and scientific quality of the studies for selecting and funding public programmers. A keyword search of Medline from 1990-2008 revealed 32 studies, and gathering of articles from other sources revealed a further 18 studies, giving a total of 50 economic evaluation studies (13 WSH interventions, 16 vector control and 21 air pollution). Overall, the economic evidence base on environmental health interventions remains relatively weak-too few studies per intervention, of variable scientific quality and from diverse locations which limits generalisability of findings. Importantly, there still exists a disconnect between economic research, decision making and programmer implementation. This can be explained by the lack of translation of research findings into accessible documentation for policy makers and limited relevance of research findings, and the often low importance of economic evidence in budgeting decisions. These findings underline the importance of involving policy makers in the defining of research agendas and commissioning of research, and improving the awareness of researchers of the policy environment into which their research feeds.

Estimating the costs and health benefits of water and sanitation improvements at global level.

The aim of this study was to estimate the costs and the health benefits of the following interventions: increasing access to improved water supply and sanitation facilities, increasing access to in house piped water and sewerage connection, and providing household water treatment, in ten WHO sub-regions. The cost-effectiveness of each intervention was assessed in terms of US dollars per disability adjusted life year (DALY) averted. This analysis found that almost all interventions were cost-effective, especially in developing countries with high mortality rates. The estimated cost-effectiveness ratio (CER) varied between US$20 per DALY averted for disinfection at point of use to US$13,000 per DALY averted for improved water and sanitation facilities. While increasing access to piped water supply and sewage connections on plot was the intervention that had the largest health impact across all sub-regions, household water treatment was found to be the most cost-effective intervention. A policy shift to include better household water quality management to complement the continuing expansion of coverage and upgrading of services would appear to be a cost-effective health intervention in many developing countries.

Global cost-benefit analysis of water supply and sanitation interventions.

The aim of this study was to estimate the economic benefits and costs of a range of interventions to improve access to water supply and sanitation facilities in the developing world. Results are presented for eleven developing country WHO sub-regions as well as at the global level, in United States Dollars (US$) for the year 2000. Five different types of water supply and sanitation improvement were modelled: achieving the water millennium development goal of reducing by half in 2015 those without improved water supply in the year 1990; achieving the combined water supply and sanitation MDG; universal basic access to water supply and sanitation; universal basic access plus water purification at the point-of-use; and regulated piped water supply and sewer connection. Predicted reductions in the incidence of diarrhoeal disease were calculated based on the expected population receiving these interventions. The costs of the interventions included estimations of the full investment and annual running costs. The benefits of the interventions included time savings due to easier access, gain in productive time and reduced health care costs saved due to less illness, and prevented deaths. The results show that all water and sanitation improvements are cost-beneficial in all developing world sub-regions. In developing regions, the return on a US$1 investment was in the range US$5 to US$46, depending on the intervention. For the least developed regions, investing every US$1 to meet the combined water supply and sanitation MDG lead to a return of at least US$5 (AFR-D, AFR-E, SEAR-D) or US$12 (AMR-B; EMR-B; WPR-B). The main contributor to economic benefits was time savings associated with better access to water and sanitation services, contributing at least 80% to overall economic benefits. One-way sensitivity analysis showed that even under pessimistic data assumptions the potential economic benefits outweighed the costs in all developing world regions. Further country case-studies are recommended as a follow up to this global analysis.

Mathematical modeling of the impact of malaria vaccines on the clinical epidemiology and natural history of Plasmodium falciparum malaria: Overview.

We report a major project to develop integrated mathematical models for predicting the epidemiologic and economic effects of malaria vaccines both at the individual and population level. The project has developed models of the within-host dynamics of Plasmodium falciparum that have been fitted to parasite density profiles from malaria therapy patients, and simulations of P. falciparum epidemiology fitted to field malariologic datasets from a large ensemble of settings across Africa. The models provide a unique platform for predicting both the short- and long-term effects of malaria vaccines on the burden of disease, allowing for the temporal dynamics of effects on immunity and transmission. We discuss how the models can be used to obtain robust cost-effectiveness estimates for a wide range of malaria vaccines and vaccination delivery strategies in different eco-epidemiologic settings. This paper outlines for a non-mathematical audience the approach we have taken and its underlying rationale.