From progress to precision: why the DRIVERS project matters for the last mile against schistosomiasis

By Dr Fiona Fleming, Prof. Poppy Lamberton, Prof. Janelisa Musaya, Dr Jean Coulibaly, Dr Sekeleghe Kayuni, Dr Justin Nono Komguep and the wider DRIVERS team

Over the past two decades, global investment in neglected tropical disease (NTD) programmes, including schistosomiasis, a parasitic disease affecting more than 240 million people worldwide, has led to significant reductions in disease burden. At the heart of this progress is preventive chemotherapy with the drug praziquantel, delivered through national programmes. In 2024, approximately 83 million school-aged children and 17 million adults were treated, corresponding to 62% treatment coverage for children and 15% treatment coverage for adults. By contrast, in 2006, only 7 million individuals were treated. This means millions of people, particularly children, are healthier and better able to attend school and work, demonstrating measurable returns on investment, even though treatment does not always completely clear infection.

However, while progress is steady in many settings, schistosomiasis transmission remains stubbornly high in others, despite repeated rounds of treatment. These “persistent hotspots” pose a challenge to achieving elimination as a public health problem, as the global schistosomiasis community moves towards this endgame. Persistent hotspots also signal the need for holistic and context-specific strategies, which consider biological responses to treatment and combine environmental improvements and enhanced sanitation practices to address the realities of each community, alongside improved mass drug administration strategies.

Understanding these final barriers and how best to overcome them is the central focus of the DRIVERS project, which seeks to explain why transmission persists, even where treatment coverage is strong. DRIVERS ultimately aims to generate context-specific recommendations to ensure strategies are more effective in clearing infections and reducing transmission. To do this, it will:

• Characterise the true worm burdens within infected individuals and how they respond to treatment to understand treatment outcomes better
• Quantify the interplay of drug absorption, immune responses, and parasite genetics and their role in the success or failure of individual treatment
• Examine behavioural, environmental and exposure factors to address reinfection
• Use data and modelling to improve the targeting of persistent hotspots and individual-level treatment within them

These insights will help refine transmission models which predict the impact of interventions and enable timely programmatic adjustments to accelerate progress as countries move toward eliminating schistosomiasis as a public health problem.

Persistent hotspots: a signal, not a setback

The focus countries of DRIVERS are Côte d’Ivoire and Malawi, where schistosomiasis prevalence is high. In these endemic communities, daily life involves frequent contact with freshwater for activities such as washing, fishing, agricultural work, or play. Seasonal patterns of movement, livelihood activities, and access to safe water and sanitation all shape how and when people are exposed to infection. In some conditions, even with regular treatment, reinfection can rapidly occur if the risk factors remain.

Persistent hotspots should not be interpreted as programme failure or evidence that preventive chemotherapy is ineffective. Rather, these hotspots reflect the growing importance of contextual factors that lie beyond the reach of treatment alone.

This challenge is not unique to schistosomiasis; similar patterns are observed in other diseases in areas approaching elimination, such as trachoma. In this sense, persistent hotspots are also a marker of progress, showing that programmes are targeting the hardest-to-reach, most nuanced contexts. Addressing persistent transmission and ensuring the sustainability of programmes means looking beyond treatment to consider behavioural, environmental, and exposure factors, an approach at the core of the DRIVERS project.

The value of local expertise and partnership

DRIVERS is grounded in equitable partnerships, from developing the research proposal to lab analyses, recognising that those closest to the problem are best placed to help solve it. Understanding transmission in persistent hotspots requires more than data alone. Partners, from affected communities and international experts to health ministries, provide invaluable insights into how factors such as occupational water contact, seasonal migration, gender roles, and access to sanitation shape exposure, treatment efficacy and reinfection in highly context-specific ways.

DRIVERS brings together these insights with data and modelling approaches, moving beyond one-size-fits-all solutions towards interventions that are tailored, locally appropriate and more likely to succeed in reducing transmission.

Focusing our resources to have the greatest impact

The emergence of persistent hotspots presents both a challenge and an opportunity. The challenge is clear: achieving elimination will require additional effort, innovation and precision. The opportunity lies in maximising the value of existing investments.

By identifying the drivers of ineffective response to treatment and persistent transmission, this research will support programmes to target interventions more effectively, focusing efforts where they are most needed and where they can have the greatest impact on health and economic development.

In practice, this could lead to more cost-effective strategies. Rather than expanding treatment alone, programmes will need to combine interventions, such as targeted snail control, improved water infrastructure, or behaviour change initiatives, in areas where they will make the biggest difference. Data driven decision-making will enable more targeted resource allocation, ensuring that investments deliver sustainable results.

Looking ahead

Preventive chemotherapy remains the cornerstone of schistosomiasis control. DRIVERS does not question its value; rather, it seeks to optimise its impact as endemic countries move towards elimination goals.

Years of investment and a global network of partners have brought us to the threshold of elimination in settings such as Zanzibar, demonstrating that with sustained commitment and targeted action, elimination of schistosomiasis as a public health problem is not just an ambition.

As persistent hotspots remain, World Environment Day serves as a timely reminder of how intrinsically linked human health is to environmental and social determinants. It underscores the importance of deepening our understanding of the key causes of maintained transmission in the most nuanced settings so that no community is left behind.

Learn more about the DRIVERS research project here.