The value of water in elimination of neglected tropical diseases: An economic perspective

Water, sanitation and hygiene (WASH) are inextricably connected to good health. Communities with insufficient access to clean water and sanitation are often vulnerable to a host of preventable diseases, including neglected tropical diseases (NTDs), which impose a significant economic burden on communities and represent a challenge for many already strained health systems.

Interventions to prevent and control NTDs are one of the “best buys” in global public health

Significant progress has been made towards the elimination of NTDs in recent years. Since 2012, 42 countries have been validated by the World Health Organization (WHO) for the elimination of at least one NTD and almost 600 million fewer people require interventions against NTDs. This progress has been attributed, in part, to the world’s largest drug donation program and the recognition that interventions to prevent and control NTDs are one of the “best buys” in global public health. Indeed, many NTD stakeholders estimate a net benefit to affected individuals of about US$25 per US$1 invested in mass drug administration (MDA) programs.

Although the cost-effectiveness of MDA has undoubtedly increased political will and action for certain NTDs, the economics of NTDs, and indeed the control and elimination of NTDs, are significantly more complex. Notably, WHO recommends that NTD programs consist of a diverse range of cross-sectoral interventions, including WASH interventions such as improving access to improved water supplies, construction of toilets and sanitation systems, and promotion of improved hygiene practices such as hand and face washing, which are essential to achieve and sustain control and elimination targets. However, many existing economic evaluations do not consider these priority areas, which may entail a higher short-term cost and whose benefits may take longer to materialise.

Narrow approaches to cost-effectiveness ignore positive impact NTD interventions can have on wellbeing

Decision-making based purely on short-term cost-effectiveness analyses can systematically neglect some of the world’s most vulnerable communities and undermine other priorities such as health equity. Communities in which the burden of NTDs is high are often the same ones that are harder and more expensive to reach with WASH services due to remoteness, environmental conditions, and small population sizes that undermine the potential for economies of scale.

Narrow approaches to cost-effectiveness ignore the positive impact NTD interventions can have on wellbeing, as they do not account for the diminished mental health, loss of productivity, and poorer educational attainment. The potential return on investment in terms of water supply is also often underestimated; whilst the initial capital investment may be high, the consequent impact can result in significant health, wellbeing and productivity gains over decades and even generations. These consequences should be incorporated into future considerations, as they exacerbate cycles of poverty and poor health and, subsequently, contribute to further marginalisation.

Do disability adjusted life years (DALYs) measure disease burden effectively?

Research suggests that generic measures of disease burden commonly used in economic evaluations, such as disability adjusted life years (DALYs), systematically underestimate the impact of NTDs because the quality of life of people with disabilities in NTD-endemic settings is significantly lower than in more developed settings. Additionally, DALYs do not include all known morbidity or negative effects associated with NTD infections. As Charles King and Anne-Marie Bertino note in Asymmetries of poverty: Why global burden of disease valuations underestimate the burden of NTDs, “the application of the DALY in policy estimates does not account for the nonlinear effects of poverty in the cost-utility analysis of disease control, effectively discounting the utility of comprehensively treating NTDs”. This is particularly true for people with NTD-related disabilities who often have a high need for clean water to manage their conditions but face increased challenges to access the water they require.

On 28 January 2021, the WHO launched Ending the neglect to attain the Sustainable Development Goals: A road map for neglected tropical diseases 2021-2030. The road map contains three fundamental shifts for NTD programmes including: 1) increased country ownership with domestic financing of NTD activities; 2) expanded and strengthened cross-sectoral collaboration to deliver comprehensive NTD programmes; and 3) impact rather than process-orientated programmes. The road map emphasises the need for close coordination and multi-sectoral action beyond the health sector, including water, sanitation and hygiene stakeholders.

World Health Organization’s Global Strategy on WASH and NTDs

To accelerate progress towards road map targets, today, World Water Day, WHO has launched a Global Strategy on WASH and NTDs – a companion document to the road map – to further set out the key measures for turning this need into a reality. However, in order to meet the full ambition of the road map, a broadening of the concept of cost-effectiveness is urgently needed that considers all relevant interventions and sectors and recognises their impact over time. A comprehensive methodology for valuing NTD interventions will demonstrate the broader impact that cross-sectoral NTD programmes have towards the achievement of multiple Sustainable Development Goals and the strengthening of health systems and communities and ensure that all people are able to realise their human rights of clean water and health, with no one left behind.

This blog was developed with contributions from Tim Jesudason – Triangulate Health Ltd, Alejandra Rodarte – Triangulate Health Ltd, David Tordrup – Triangulate Health Ltd, Yael Velleman – SCI Foundation, and Katie Fantaguzzi – SCI Foundation

Sign up to SCI Foundation’s mailing list here