Social Science and Neglected Tropical Diseases in Cameroon – So what?

By Samantha Page, Laura Dean, Estelle Kouokam, Fabrice Datchoua, Hermine Jatsa Boukeng, Christian Duamor Tetteh, Mary-Sheena Maingeh, Manuela Ngo Bakale, and Theobald Nji

We recently completed the first social science meeting in Cameroon for COUNTDOWN where colleagues from The University of Buea, The University of Yaoundé and Liverpool School of Tropical Medicine came together to develop collaborative social science research protocols for COUNTDOWN. So what?

Using methods from social science generates important data that has the potential to reduce the prevalence of Neglected Tropical Diseases (NTDs) in Cameroon; data which cannot be captured from the biomedical sciences. However social science methods are often overlooked when addressing NTDs, or even sneered at.  Many ‘pure’ scientists cannot understand the value of conducting social science or what impact this academic discipline has in addressing these so called “diseases of poverty”.  So what?

So this is one of the challenges we face when working on a multidisciplinary programme that involves social science, parasitology, entomology, and vector biology. To combat this challenge we have come up with key research questions addressing each level of the health system in Cameroon, of which there are five: national, regional, district, health area and community.  These research questions can be grouped across five core areas which are critical to a holistic approach to NTDs. These are:

  1. Funding, governance and donor priorities;
  2. Health system integration and disease programme co-implementation;
  3. Partnerships and multi-sectoral working beyond the health sector;
  4. Community drug distributors; and
  5. Gender, disability, equity and NTDs.

So what does this mean in practice?

At the national level through key informant interviews and stakeholder workshops, linked to the research area of funding, governance and donor priorities, we will explore how donor priorities influence the way programmes are managed. In addition, we will assess how decisions made internationally support or challenge country priorities and processes for NTD control and elimination.

At the regional and district level through key informant interviews, stakeholder workshops, focus group discussions, direct observation and document review, linked to the research area of health systems integration and co-implementation, we will seek to understand how current platforms for NTD co-ordination are functioning and promoting co-implementation of disease programmes.

At the district level through key informant interviews, stakeholder workshops, focus group discussions, and direct observation, linked to the research area of partnerships and multi-sectoral working, we will identify what multi-sectoral partnerships are in place and what opportunities are missed.

At the health area level through participatory methods such as ‘photo-voice’, linked to the research area of community drug distributors, we will identify how community drug distributors are currently supported and co-ordinated by and within the health system. We will explore how their role within communities can promote community ownership of the philosophy of eliminating NTDs.

At the community level using anthropological methods such as ethnographic journals, linked to the research area of gender, disability equity and NTDs, we will seek to understand how communities perceive and talk about NTDs and how we can be more responsive to their understandings, particularly in the way we generate health education messaging. We will consider the needs of individuals currently ‘invisible’ to existing NTD programmes, such as out of school children, people living with disability and pregnant women.  We will assess how stigma and disability present barriers in accessing treatment for NTDs.

The collaborative nature of social science within COUNTDOWN is not limited to work in Cameroon. Our work in Ghana takes a similar approach and the same is likely to be true in Liberia and Nigeria. So what?

Well, this allows for learning between these diverse African contexts who are in differing phases of disease control to address bottlenecks and implementation dilemmas to accelerate the elimination of NTDs. So what?

Social science may have a long way to go to prove its worth in the field of NTDs, but we believe that without it, elimination and eradication of diseases propagated by social processes is impossible. The medicines, the public health strategies are there. So what?

Control and elimination cannot succeed without the understanding and the explanation of the social process, social organisations, beliefs and perception of societies that are the principal actors and people affected by NTDs.


Defining Lymphatic Filariasis hotspots in Ghana

By Lisa Reimer, Liverpool School of Tropical Medicine

We must appreciate the heterogeneities of NTDs across communities and understand the factors that have resulted in persistent disease, only then can we apply a sustainable strategy for elimination.

Lymphatic Filariasis in Ghana

Lymphatic Filariasis (LF) is a mosquito-borne infection caused by filarial worms that can result in significant illness, disability and disfigurement. The LF Elimination Programme in Ghana has achieved great success with annual, community-wide distribution of microfilaricides. It is recommended that the drugs are distributed to the entire community for 5-7 years which is the estimated life span of adult worms. Mass drug administration (MDA) has been underway for over ten years, but there are still communities endemic for LF. So what is unique about these communities? Why has the recommended strategy failed to eliminate LF? Will scaling up MDA provide the final push towards elimination?

Hotspots and heterogeneities

These communities are often referred to as ‘hotspots’ and they are likely a product of the heterogeneous nature of vector-borne diseases. For example, there is great diversity among the vectors of LF ranging from those that are highly competent to incompetent, those that bite indoors and those that bite outdoors, those that preferentially feed on humans and those that are generalist feeders. There may be differences in village characteristics that can support a larger population of the most capable vectors. There may be greater risks to certain individuals of a community depending on their habits, house structure, house location and their occupation. There will be individuals in a community who decline treatment, are unavailable during distributions or prefer not to use a bed net. There may be other barriers to delivery of services and interventions. There may be differences in insecticide resistance or drug resistance influencing the efficacy of MDA and vector control.

It may not be enough to scale up access to MDA, we need to understand the dynamics that have contributed to persistent transmission in these communities in order to inform the most appropriate delivery of interventions.

Planning for change

I recently met with COUNTDOWN colleagues Dr. Benjamin Marfo, Dr. Nana Kwadwo-Britwum and Dr. Margaret Gyapong from Ghana Health Service and Dr. Mike Osei-Atweneboana from the Council for Scientific and Industrial Research, to lay the groundwork for our investigation of lymphatic filariasis hotspots in Ghana. We are planning an in-depth investigation into the social, entomological and epidemiological factors that are driving transmission. We will evaluate current epidemiology in the context of baseline prevalence. We will explore adherence to MDA, bed net usage, transmission, vector behaviours, vector competence, insecticide and drug resistance, community beliefs and practices, experiences of the health workers and drug distributors. This understanding will then inform a new approach to integrated delivery of vector control and MDA. Our study will evaluate the costs, experiences and the impacts of integrated complementary strategies for LF.

We are now making plans for our first visits to study communities in January 2016. I am particularly looking forward to joining postdoctoral researcher, Dr. Kingsley Badu for our mosquito surveys to evaluate vector behaviours and current transmission dynamics.

The Ebola outbreak and the wider health system: understanding impact and the way forward in Liberia

By Laura Dean, Anthony Bettee, Kate Hawkins, Sally Theobald and Karsor Kollie

During the recent Ebola outbreak Liberia lost over 185 of its professional health workforce. Trust between health workers and communities broke down and resources were diverted from routine health system activities to control the outbreak. This resulted in the near collapse of the health system as well as changes in the disease landscape and increased vulnerabilities related to the social determinants of health for many people.  As the health system is rebuilt, it is critical that the full impact of the outbreak at all levels of the health system is understood from the perspective of different stakeholders, in order to put forward strategies to strengthen the resilience of the health system.

Small grant

In collaboration with the Ministry of Health in Liberia, COUNTDOWN colleagues were recently awarded a small grant for research engagement from the Thematic Working Group on Health Systems Research in Fragile and Conflict Affected States. We will use this to convene two stakeholder meetings, one at the national and one at the county level that explore the impact of the Ebola outbreak on the health system with a specific focus on  the Neglected Tropical Disease (NTD) control programme. We aim to highlight the opinions of people whose voices are often not heard at such meetings, for example community members and frontline health staff. We hope these meetings will provide a unique opportunity to gain deeper understanding of the impact of health system collapse on vertical programmes and explore how these programmes can help support the wider system.

The Neglected Tropical Disease Programme in Liberia

The NTD control programme in Liberia is an integrated programme established in 2012 that engages with the health system from central Ministry of Health to the community level. During the Ebola outbreak the NTD programme ceased activity in order to support Ebola control, however it is now slowly beginning to resume activity. However before it starts up fully there is a need to understand in more detail the challenges faced in NTD control both prior to and since the Ebola outbreak. The stakeholder meetings allow reflections on the operations of the NTD control programme prior to the Ebola outbreak, as well as assessing how the Ebola outbreak may allow for a revitalisation of the programme to achieve a scaled-up, equitable response to NTDs in Liberia.

Follow up

As a result of the meeting we hope to develop a research agenda for health systems with specific focus on NTD control in Liberia that we can begin to address within COUNTDOWN. The engagement of international stakeholders from other Ebola affected countries such as Sierra Leone aims to increase the transferability of this research agenda and its findings, as well encouraging south-south collaboration and lesson learning as health systems are rebuilt. Watch this space for more information and outputs from COUNTDOWN’s first stakeholder meeting in Liberia!

Image: Courtesy of UNMIL/Emmanuel Tobey

Work on Neglected Tropical Diseases in Brazil provides lessons for the Africa region

By Russell Stothard Brazil has a significant burden of Neglected Tropical Diseases (NTDs) but these often differ to those in sub-Saharan Africa. For example in Brazil, there are no tsetse flies and thus there can be no transmission of human sleeping sickness. However, other blood sucking insects abound and in rural areas, triatomine bugs act as the principal vectors of Chagas disease, a major blight throughout South America and is the leading cause of heart failure. Infection with this single-celled parasite is typically chronic and drug treatment is largely ineffective when the disease progresses towards its later stages, where nearly all muscle tissues can be parasitized. Several years ago when working at the London School of Hygiene of Tropical Medicine with Professor Michael Miles, we showed that the parasite Trypanosoma cruzi underwent sexual reproduction in such tissues highlighting its capacity for  rapid evolution within the body. Of the early leading names in tropical medicine, two researchers Oswaldo Cruz and Evandro Chagas, are not as well-known in Europe as they should be, both being eclipsed perhaps by Patrick Manson and Ronald Ross. Nonetheless, Cruz and Chagas have left a truly impressive legacy in Brazil with the FIOCRUZ which is celebrating its 115 anniversary. Today FIOCRUZ employs over 11,000 staff and maintains a highly-regarded hospital and conducts an impressive portfolio of applied health research from the production of vaccines, drugs, reagents and diagnostic kits to education and training and engagement with its many social programmes focused on disease control. Within the UK we have much to learn from the approach taken by the foundation on how integrated control can proceed across a range of areas of health.

Carlos Chagas and team

Charlos Chagas with his team (Fernando’s grandfather is in the middle row on the right-hand side)

Being a speaker at ARTHROMINT 2015 meant I had the good fortune to visit the FIOCRUZ castle and see first-hand the library where Cruz and Chagas once worked. The history really does seep from its walls as I learnt from my hosting colleague Dr Fernando Monteiro, who works on the molecular systematics of Triatomines, that his grandfather was part of Chagas’s team and that his family has maintained a long connection with the institute. Having also worked on triatomine bugs before, it was a pleasure to give my research seminar at the institute and highlight more recent work on schistosomiasis and the implementation research that COUNTDOWN will conduct on several other NTDs, that often parallels similar challenges in Chagas disease control.

Speaking about schistosomiasis in Brazil is highly appropriate, for intestinal schistosomiasis is a major health hazard in rural populations where water hygiene and sanitation is poor. There is also a longstanding national control programme also focused on curative treatment with praziquantel (PZQ), however, there are key differences in approach when compared to those in Africa. Foremost, PZQ treatment is given out on a selective basis rather than in community-wide programmes. Hence, for a child to receive treatment (s)he must be shown to have evidence of infection upon the occurrence of schistosome eggs, the frontline diagnostic being the Kato-Katz stool examination in a ‘test and treat’ strategy.

Whilst this classic parasitolological method is also used in Africa, the necessary man-power and resources within the health system to provide this service to each child annually is outside the reach and resources of many Ministries of Health. Hence only community-wide application is possible or recourse is needed to more field-friendly diagnostic methods such as rapid urine antigen tests. Discussions with Octavio Pieri, the Brazilian national control programme co-ordinator, demonstrated a range of experiences in the Brazilian programme which it is important to share across the Africa region. Themes emerged such as the need for better PZQ dosing, treatment of marginalised groups (e.g. pregnant women and preschool children) and cross-talk with health education and water sanitation sectors. ARTHROMINT 2015 was a great success and I now look forward to discussing further in August how schistosomiasis control programmes can be optimised, especially in promoting access to PZQ in young children, across the transition from control to elimination settings.

Intestinal schistosomiasis in Uganda: Taking advanced diagnostics to the lakeshore

By Hajri Al-Shehri

Neglected Tropical Diseases (NTDs) are often a symptom of poverty and challenging living conditions. Those who are most affected are the poorest people living in remote rural areas, urban slums or in conflict zones. Schistosomiasis, for example, is often found in populations with very limited access to safe water and in environments poorly served by primary health outposts as typified by out-of-stock drugs and inadequate diagnostic testing. The lack of reliable statistics reporting on treatment and disease has kept the true burden of schistosomiasis in the shadows and failed to identify the inefficiencies of control programmes that are committed to reach those most in need of treatment.

I have just returned from a three-week epidemiological study on the shores of Lake Albert, Uganda. Working with Vector Control Division (VCD), Ministry of Health, Uganda we visited five rural primary schools in Hoima and Buliisa Districts, examining just over 50 children per school with a combination of diagnostic methods.

Performance of diagnostic tools in a high prevalence settings

urine antogen testsOur basic analysis revealed that in three schools on the immediate lakeshore, prevalence of active intestinal schistosomiasis was just over 85%. With such high levels detected, it is taken for granted that these children are in regular contact with contaminated water, remaining a daily way of life and mitigates the impact of the national control programme (NCP). The Uganda NCP started in 2003 and has been providing annual treatment of school children with praziquantel (PZQ) for over several years. But despite best intentions, it is clear that annual treatment is failing on the lakeshore and needs to be strengthened. Our clinical assessments showed substantial amounts of morbidity in these unfortunate children with swollen livers, numerous schistosome eggs and blood in stool as well as enlarged tummies.

My thoughts on successful fieldwork

Fieldwork is not just an important, stimulating and often challenging part of the research process I undertake; it also offers a wonderful way of seeing the world, and a chance for personal development. The key points are to understand theory, develop skills, integrate and build tacit knowledge, develop alternative solutions for the problems in certain places, and work cooperatively with a team. Despite our best efforts in preparations, fieldwork constantly offers surprises and ad hoc solutions that may fail miserably for many reasons: a sudden rainstorm reduces time at the study site, your way back to camp is blocked by a flood and you endure water-logged muddy roads that drain your energy, as does our intermittent camp electrical supply as our portable generator fails then you are hounded by irritating lake flies that dance around your head torch while you concentrate at the microscope. Conditions in the field are often unpredictable and can affect your aims in different ways sometimes being left frustrated but when you overcome these obstacles you have good reason to be proud and satisfied.

car in UgandaSo what are the ingredients for successful fieldwork? I now realise that fieldwork should have clear vision of what you want to accomplish but be flexible within a set of integrated goals and contingency plans that can be brought rapidly into action when needed. For example, assessing each day everyone’s workload, checking in-field logistics and sampling techniques is essential to adapt to local conditions, as well as having enough in reserve to put in extra effort when required. Before leaving to Uganda, my supervisor and I had many discussions during the planning process who explained the theory but I have now the practice. The key ingredient is that there is a small window of opportunity to get the survey right where all the necessary equipment, reagents and team’s skills are brought together at the right place and at the right time, ensuring that these remote communities can be well-attended. Only by doing so can the true burden of NTDs be brought out of the shadows and highlight today’s treatment needs. I am proud to have made an important contribution to the Uganda NCP with our colleagues from VCD.  

About the author

I was born in Asser, Saudi Arabia, and have worked there for several years as a specialist in molecular diagnosis of infectious diseases in Asser Central Hospital. Being based in this busy clinical laboratory, I have developed interests in Neglected Tropical Diseases, especially schistosomiasis, and completed an MSc degree in the UK in Biomolecular and Biomedical Sciences, Faculty of Life Sciences & Medicine, at Glasgow Caledonian University. To further extend my qualifications and broaden my experience, I started my PhD in June 2014 at the Liverpool School of Tropical Medicine with Professor Russell Stothard and decided to focus on the epidemiology and control of intestinal parasites. My project hopes to compare the performance of state-of-the-art diagnostic tools in high prevalence versus low prevalence settings and understand how these tools can be applied in my own country where schistosomiasis and soil-transmitted helminthiasis are nearing elimination. Writing a science blog helps me stay motivated and by sharing my recent fieldwork in Uganda, and highlights what I have learned.


Hot topics in schistosomiasis

COUNTDOWN has been busy this week at the mini-symposium on ‘hot topics’ in schistosomiasis at Leiden University Medical Center in the Netherlands. Russell Stothard represented the Consortium and says:

“I am delighted to present at Leiden amongst friends and colleagues who have contributed so much to the advancement of tropical parasitology. I will present our recent experiences in Uganda and Namibia where we have used the CCA test and also uncovered that there are still barriers to its effective deployment within the health system. This is something which we will hope to address more specifically in COUNTDOWN to ensure that preventive chemotherapy approaches against schistosomiasis have the future impact we expect of them.”

Read more…

The history of innovation in Neglected Tropical Diseases: Some useful points from Jürg Utzinger

By Rossely Paulo

Jürg Utzinger (Swiss Tropical and Public Health Institute) was one of the key note speakers at the recent meeting of the British Society for Parasitology. He gave a great overview of some of the history of Neglected Tropical Diseases (NTDs) and areas where innovation is needed.

NTDs: Where did the term come from?

Three of the eight Millennium Development Goals are health-related. Although NTDs were not specifically mentioned, Goal 6 is focussed on combating HIV, malaria, TB and other diseases. Jürg explained that the conceptual framework of the Neglected Tropical Diseases was formulated in the years following the 2000 launch of the Millenium Declaration. NTDs, as a concept, went on to be popularised in seminal papers written by David Molyneux, Peter Hotez, Alan Fenwick and David Rollinson. Many at this time were arguing that it is important to look across the spectrum of the diseases that particularly affect poorer people in low-income settings rather than singling out a few priority illnesses. An initial list of NTDs was drawn up that clustered together 15 complaints.

Innovation in work on NTDs

Jürg explained that large–scale, longitudinal, community-based surveys have provided a great opportunity to drive innovation in NTDs by allowing us to assess population risk and guiding interventions for control and elimination.

But challenges remain

For example the current anthelminthic drug – albendazol and mebendazole – have a low kill rate against Trichuris which lead us to the conclusion that there is an urgent need to develop new drugs. One alternative could be multiple dosing of existing drugs which decreases the Trichuris parasitemia rate, the hardest parasite to cure. Diagnosis of various NTDs such as S. mansoni are still largely dependent on stool examination based on the Kato-Katz thick smears technique. But this has become a big concern due to its low sensitivity particularly in low-endemicity areas. Therefore, more sophisticated diagnostic techniques are required such as the Point-of-Care urine assay for the detection of Circulating Cathodic Antigen (POC-CCA) and the multivalent faecal egg count (FLOTAC) methods which are three times more sensitive than Kato-Katz. There is a need for more integrated control programming which brings together different sectors. Jürg pointed to efforts in China and Zanzibar where work on schistosomasis control and elimination is based on working with stool samples, agricultural factors, Mass Drug Administration, snail control and vector behaviour as examples of interesting practice.

The future

NTDs are finally on the radar screen of policy makers but how do we sustain these positive developments. We have some tools for control and elimination but they are insufficient! We need constant innovation and validation of the tools and strategies. Jürg ended by stressing that innovation is crucial to prepare and be ready for the future and that collaboration, communication and partnership are the absolute keys to success.

“The final mile is often the most difficult one”: Launch of the third WHO report on Neglected Tropical Diseases

By Kate Hawkins, Pamoja Communications The WHO report on Neglected Tropical Diseases (NTDs) was launched yesterday with a simultaneous live feed that linked Addis Ababa and London.  Here are four issues that dominated the conversation:

  1. Money, money, money

The report outlines a business case for the control of NTDs both on cost effectiveness and equity grounds. It was suggested that meeting NTD Road Map targets for 2015-2020 requires $750 million a year (not counting vector control). Maintaining progress from 2020-2030 requires an additional $460 million a year as programmes are scaled down.  There was agreement that endemic countries will need to do more to raise the revenue required to fund this push and Baroness Northover (UK Parliamentary Under Secretary of State, Department for International Development) suggested that parliamentarians have a key role to pay in lobbying Ministries of Finance to allocate more to health budgets.

  1. NTDs as a litmus test for universal health coverage?

At the meeting we were reminded that universal health coverage is also about equity and ‘ensuring that nobody is left behind.’ In the case of NTDs this includes the poor in middle income countries.  The report describes them as a litmus test for universal health coverage, and Margaret Chan is quoted: “We are moving ahead towards achieving universal health coverage with essential health interventions for neglected tropical diseases, the ultimate expression of fairness. This will be a powerful equalizer that abolishes distinctions between the rich and the poor, the privileged and the marginalized, the young and the old, ethnic groups, and women and men.” Strong words…although presumably this will be part of a larger social and political project of tackling the norms, institutions, and structures which create and maintain such divides.

  1. Equity

Andrew Jack of the Financial Times described NTDs as conditions that effect, rural, remote, neglected, and abandoned people. They effect poorer people and because they effect physical development, educational attainment and are often disabling they can also have an impact on people’s ability to generate a livelihood. The report states, “The inclusion of an equity focus in policy-making will become more and more important the closer countries get for achieving the targets for the Roadmap. Such a focus will help justify sustained efforts in the remaining number of NTD hot spots where unit costs begin to increase just as the scale of operations begin to decrease.”

We heard little about gender at the launch, although Baroness Northover mentioned that NTDs disproportionately affect or impact upon women and girls. If this is an area you are interested in you might like to check out this review of gender and NTDs that our colleague Margaret Gyapong co-authored way back in 2005 for some background.

  1. Integration

There was consensus that collaboration is necessary if we are to make impact on NTDs. To tackle NTDs will require the health sector to work with their colleagues in water and sanitation, the environment, vector control and the veterinary sciences. A task made more tricky by climate change, urganisation, and increasing migration in many settings. It was noted that governments, the private sector, researchers, multi-lateral and bilateral donors, and non-governmental organisations all have complimentary roles to play. People were hopeful: Nigel Crisp (Chair of Sight Savers among many other roles) described the area of NTDs as ‘global solidarity actually working.’ The perennial issue of vertical versus horizontal approaches to health programming and system support raised its, now very familiar, head. Some argued that NTD programmes were a shining example of integration at its best. Others that these diseases occur in settings where there is little existing infrastructure and that there is an argument for kick starting action through vertical programmes and moving to an integrated and comprehensive approach over time. Tim Evans (World Bank) pointed to the success of Ivermectin programmes in creating community systems and structures that provide a host of other services to the poor, and poorly served. I left the meeting with the feeling that there have been many positive developments in the world of NTDs. There is much to be hopeful about and maintaining a positive sense that change is possible is important. However, I also heard talk of growing inequality, Ebola, environmental fragility, civil unrest, and conflict – all of which make real world action on NTDs all the more challenging and complicated than it at first appears.

An introduction to Rossely Paulo

I’m a microbiologist from Angola and I’ve just started my PhD on understanding of the spatial and temporal micro-epidemiology on Neglected Tropical Diseases in the province of Bengo, Angola. The aim of my research is to be focused on vector prevalence based on the molecular, geographic information system mapping and spatial analysis where it will confirm the endemicity of filariasis and schistosomiasis and how their co-endemicity can affect the mass drug administration of albendazol and ivermectin respectively. This will develop my long term interest on parasitic conditions – very important diseases in my country.

I’m from the e-generation, I realise that writing scientific blogs is important, not only to enhance my research while doing my PhD, but also to share my personal experiences and increase the awareness of Neglected Tropical Diseases. So, on my first day of the PhD programme I was lucky to attend the lecture by Russell Stothard, my supervisor, to the Wilderness Medical Association, a student group in University of Liverpool, “Tips in field epidemiology: Just get out there and be well prepared”.

Expeditions in medicine give you a little bit of wilderness, especially when you go to the tropics, and this lecture aimed to inspire the audience how to practice proper medical research outside the hospital. It also emphasized that this is a strength of the type of study at Liverpool School of Tropical Medicine.

Learning more about schistosomiasis

To set the scene we heard an introduction to schistosomiasis, including its life cycle, its pathology, and a cultural analysis of the impact of the disease. Even after 150 years of research, there’s always something new to be learnt from archives. For example, in the seminal observations by Professor Robert Thomson Leiper in Egypt which he wrote while seconded to the Royal Army Medical Corps which bring together the best principles of wilderness and tropical medicine.

Today, 90% of the cases of schistosomiasis occur in Africa, and it is vital to put this disease on the global radar and to increase efforts to control it. The interesting bit about studying schistosomiasis is that you can actually become a gastroenterologist, a urologist, or even a neuroscientist (if you want to study its rarer neurological conditions)!

Schistosomiasis is a major health concern. In countries such as Tanzania, where urogenital schistosomiasis is highly endemic, some people in rural areas think that boys also have a type of menstruation. In reality their children urinate blood due to the presence of the parasite. Blood in the urine is a classic sign of urogenital schistosomiasis and is not always completely understood.

The three skills vital for those interested in conducting an expedition are: Patience, practice and perseverance

At the lecture we learnt that is important to be meticulously organized for an expedition, which means having a contingency plan, materials double-checked, carefully plotting a route, and having research documents ready. One week in the field usually takes about five or six weeks of prior organisation. All this can be found fully explained in the excellent field manual by Sheppard, the Vehicle-dependent Expedition Guide. It is also important to be very precise with communications, especially dealing in complex local languages.

Russell reported on his experiences in Lake Victoria during an expedition in 2010 with the aim of mapping schistosomiasis across the Sesse Islands. A video about the survey was shown, where freshwater snail and parasite collection methods could be seen and the techniques used to take GPS points and pH measurements. These surveys revealed a large burden of the disease which was previously unreported.

This lecture provided the taste of my future research and I’ll be joining the annual conference of the British Society of Parasitology in April on malaria, Neglected Tropical Diseases and vectors. Would you join me? If yes, please register and help place these issues on the global health agenda.

COUNTDOWN in WHO: Discussing new diagnostics for schistosomiasis control

Russell Stothard, Liverpool School of Tropical Medicine

Last week I was in very interesting discussions with a panel of around 40 international technical experts, brought together by WHO-Geneva to review and revise the application of new diagnostics for the control of schistosomiasis. The meeting was expertly chaired by my longstanding colleague and friend Narcis Kabatereine, and, from the outset it was clear that discussions would be complex.

We covered many diagnostic nuances that ranged from the biomarkers and mechanics of the tests themselves to how these tests might be deployed and used appropriately to guide treatment decisions in the large-scale use of praziquantel. Some of these issues were covered in our special issue of Parasitology which is useful background reading.

Complexities in diagnosis

To me, it was hardly a surprise that consensus was difficult to reach as we all often want different things. It is the subtle distinction between active infection versus chronic disease that causes so much confusion and blurring in schistosomiasis diagnosis. Without wishing to digress too much, it hangs on the distinction between schistosomiasis versus schistosomosis. The later terminology was adopted in veterinary helminthology as an attempt to resolve the tensions in disconnect between infection and disease, but it was never accepted by the medical community. Perhaps, this was a mistake as an imprecise terminology begets confusion and mixed objectives.

In short; infection (schistosomiasis) is caught by exposure to water infected by larval stages, these larval stages mature to adult male and female worms that pair and mate. The fertilised female sheds numerous eggs each day into the blood stream which are either voided in the urine/faeces or become trapped in internal organs. As the eggs secrete potent toxins, trapped eggs induce a very strong inflammatory reaction and with it the gradual accumulation of lesions, these then conglomerate into fibrotic masses that irreversibly disease the body (schistosomosis).

The worms themselves are relatively benign but their laid eggs, however, are not. Also the numbers of voided eggs in urine/stool versus those accumulating in tissues is not clear, especially when exit sites of the eggs become progressively blocked.

The relationship between the numbers of adult worms, excreted egg tallies in stool or urine, and the trapped eggs accumulating in tissues reacting with the immune system is complex and not straightforward. Typically in advanced disease, adult worms may not be present having died or excreted eggs fall below detection thresholds, however, the long-lasting lesions around trapped eggs remain causing mischief. All this can have the rather perverse consequence that rampant late-stage clinical signs of diseases, like in Female Genital Schistosomiasis, may be misinterpreted by those who place too much importance on diagnostic tests of active infection (i.e. eggs in stool).

This is like inspecting the damage of a crashed car by looking at its current speedometer reading, where you would be mistaken to think it never moved, but you can of course check its milometer. Unfortunately for schistosomiasis no such cross-check is possible and by analogy not all crashed cars have the same mileage, thus like schistosomiasis (or rather schistosomosis), advanced disease may have completely different presentations following from different durations and rates of the accumulation of trapped eggs.

In areas where there is high transmission and reinfection, treatments with praziquantel slows down the milometer and in so doing averts severe disease.

Point of care diagnosis?

The main thrust of the WHO-Geneva discussion was the acceptance of a point-of-care dipstick which detects schistosome circulating cathodic antigen (CCA). Several of us have shown it to be proven useful for detection of Schistosoma mansoni infection. The advantages of this test are that it is quick, low cost (about $1.5), easy to perform, rapid and with high diagnostic sensitivity. Above all it uses urine samples rather than faecal samples which is easier to collect.

Faecal samples are used for the Kato-Katz test which is the backbone diagnostic method for nearly all faecal helminths, and it was delightful to see Naftale Katz, one of the originators of the test, at the meeting. Naftale is still going strong after 50 years of research and control into intestinal schistosomiasis in Brazil.

Switching from Kato-Katz to the CCA test raises a whole raft of related questions: how can it be used in disease mapping and surveillance; can it be produced in sufficient supply to fulfil future demand; how will its use change the treatment algorithms for praziquantel etc.?

The long road to the WHO

Ten years ago I was the first to evaluate the test for its use in control programmes in East and West Africa. Even then I was convinced that it had an important future role to play in guiding control, especially when you had small teams working in remote areas where it was difficult to carry in equipment. I remember very vividly taking boats to distant islands in Lake Victoria and uncovering alarming levels of disease on those island communities simply because we were the very first to travel there with field-based diagnostic tools. Using the CCA in combination with Kato-Katz and ELISA testing in later work, we also mapped the disease on the Sesse Islands, proving it to be much more extensive there than previously thought.  However, it has taken several more papers, large-scale funding by Bill & Melinda Gates Foundation via SCORE and several years of advocacy to place the test in front of the eyes of WHO-Geneva for their reconsideration of current diagnostic guidelines.

It was a long journey indeed, and we should not be proud of taking such a prolonged time to put operational research into revised control actions. Had the CCA test been used several years ago in large-scale control programmes we would likely have seen increased use of praziquantel because the Kato-Katz test tends to underestimate the ‘true’ prevalence of schistosomiasis. I ask myself in this elapsed time period how many thousands of children and adults who could have been treated that weren’t? It disappoints me that international advocacy does not quantify these deficits. If we did it might prompt swifter decisions.

One of the major tasks ahead in COUNTDOWN is to turn best evidence into best practice as quickly as possible. This is our driving rationale if we are to be successful in the scale-up of praziquantel treatment and in acceleration towards NTD control targets…so watch this space.

Photo courtesy of the United States Mission Geneva