RSTMH broadens its horizons

30 Sep 2010

Wendie Norris

Source: TropIKA.net

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The Royal Society of Tropical Medicine and Hygiene.

One hundred and eighty delegates, including students from Malawi on Gates Foundation scholarships, attended the biennial meeting of the UK’s Royal Society of Tropical Medicine and Hygiene, held in Liverpool 8–10th September and entitled “Global Health Challenges 2010 and beyond”.

The conference looked beyond the traditional topics of neglected tropical diseases and vector control, to consider issues such as health systems in fragile states (on which topic there were strong contribution from NGOs), changing behaviour patterns that impact health, and whether new molecular tools will help us achieve the millennium development goals.

Though focussed primarily on developing and tropical countries, the meeting considered relevant information from Europe and North America: for example, lessons learnt from handling pandemic flu outbreaks, and the health risks faced by immigrant populations from areas endemic for Chagas disease. There was also a timely reminder that we all need to monitor our handwashing habits – something researchers are currently doing in a UK motorway service station!

RSTMH medals were presented to Professors Vikram Patel (unavoidably absent), Malcolm Molyneux, Juerg Utzinger, Tran Tinh Hien and Nicholas White. Professor Adetokunbo Lucas, a former director of TDR and Professor of Public Health, Harvard, launched his autobiography, describing his lifelong journey “From local to global health” [1].

Vector-borne diseases
(Chair: Professor Janet Hemingway, Liverpool School of Tropical Medicine, UK.)

Experience shows that the use of insecticides leads to resistance, so targeted vector control based on repellents or attractants is appealing. And sometimes a radical rethink (as by Médicins sans Frontières [MSF]) is required.

Volatile “semiochemicals” that attract Musca sorbens – one of the most important fly vectors of trachoma – to young children and to human faeces have been isolated by Julie Bristow of the London School Tropical Medicine & Hygiene (LSTHM). These chemicals could be used in monitoring traps or in home flytraps, avoiding use of insecticidal sprays. Having shown that faeces of humans are supremely attractive compared with those of other animals (herbivores just aren’t as interesting to M. sorbens), and that the fly prefers children with a pre-existing ocular discharge, Bristow went on to isolate 11 semiochemicals from faeces and one from ocular discharge.

Chagas disease is endemic in Bolivia, where 95–99% of treatment needs are still unmet. There are two to six deaths every day, according Dr Tom Ellman of MSF. Chagas is a disease of poverty; adequate tools and funding are lacking. The development of a cure is hindered by the fact that the consequences of the infection take 20–30 years to develop. We do know the vector and the habitat (adobe hut roofs) and there are drugs, but the most effective treatments are not available in Bolivia. Vector control has brought down the incidence in children but not in adults. MSF’s new radical approach for Andean villages is focussed on education and improved housing.

Malaria eradication – organism, vector or disease?
(Chair: Professor David Molyneux, Liverpool School of Tropical Medicine, UK.)

Representatives from the Gates Foundation, WHO, the research community and “countries on the receiving end” debated the Foundation’s goal of eradicating malaria.

Agreement that integrated approaches are the way to successfully eradicate the disease was tempered by the realization that it could take 40 years and will require:

new control measures, insecticides and drugs to combat resistance
vaccines
tactics that depend on factors in individual countries.

Professor Molyneux reminded everyone that we need to agree on what is meant by “eradication” and to recognize that it goes beyond elimination as a public health problem. He defined eradication as “reduction to zero of worldwide incidence, no further intervention needed”.

Dr Chris Whitty (DFID, LSTHM) pointed out that, as one nears the endpoint of an eradication campaign, the cost of finding the remaining carriers of the disease escalates, and the international community and donors must stay committed, politically and financially.

Child health and development in a global recession
(Chair: Professor Donald Bundy, World Bank, Washington, USA.)

Professor Bundy (co-author of School Health, Nutrition and Education for All Levelling The Playing Field [2]), highlighted some positive effects of the recession: various countries including “rich” ones have approached the World Bank for support to introduce safety net programmes. Pre-2009, school-feeding and deworming programmes, despite longstanding evidence, had still not been implemented. Since then, Kenya has brought in deworming and has reached 86% of children within an astonishing three months. Russia and China now wish to follow India’s lead into national school feeding.

Global pandemics
(Chair: Dr David Heymann (WHO and Health Protection Agency, UK.)

The UK’s experience of handling pandemic flu outbreaks dominated this session, providing insights into contact tracing (illustrated by experience in an outbreak in state schools in southeast London) and asymptomatic infection detection (a boarding school outbreak), as well as the First Few Hundred Project.

The presentation of Robert Pool (Barcelona Centre for International Health), entitled “Could vaginal lubricants lead to safer sex?”, arose from a 9000-participant microbiocide gel trial for reducing HIV/AIDS transmission. The microbicide didn’t work but the gel itself transformed the sex lives of the women, especially where “dry sex” was practised, leading to safer sex: husbands did not stray and condoms could be negotiated. This unexpected result should inform future programmes.

Changing behaviour: why is it so hard?

Anthropologists and social scientists are working alongside tropical disease specialists to identify the behaviour patterns and belief systems that keep people unhealthy.

“We won’t buy a shoe to improve our health but we will buy one if it’s pretty, comes in many colours and sizes, is easily available and says ‘made in Paris’!” declared Val Curtis (LSTHM), who went on to discuss her work on “handwashing with soap” campaigns. Using a “human motives model” and commercial marketing techniques has enabled her team to understand what drives people to handwash with soap. (It is primarily a consequence of the disgust and nurturing instincts.) . They have also been able to devise effective national TV and radio campaigns, for example in Ghana. Fifty per cent of everyday behaviour is routinized, and washing/ritual cleansing is a habit acquired in childhood, so we need to know how to “insert” washing with soap into the routine. Using desire, as advertising companies do, is an effective way to promote healthy habits.

Neglected (tropical) diseases (NTDs)

Dr Amadou Garba reported that Niger has rolled out a national integrated control programme, for not one but four diseases: schistosomiasis, lymphatic filariasis, soil-transmitted helminths and trachoma (see TropIKA.net News). Launched in 2007 in three regions (with 6.2 million people), the programme reached national coverage in 2010 (12.5 million people). The key to success was mobilizing government officials and TV for the launch and training of community drug distributors and local surgeons in disease management. Similar efforts are under way in Uganda, according to Dr Sam Zaranda; all officials dealing with these diseases (plus onchocerciasis), now have their offices in one building (the NTD Secretariat), in order to encourage coordinated efforts.

Can cutting edge science help us to reach the MDGs?

MDG 6 aims at a 50% reduction in TB cases. To achieve this we need to cut transmission rates. This requires, amongst other things, a same-day, more sensitive diagnostic test – one that works in the context of HIV co-infection and preferably distinguishes between latent and active infection. (Only 5% latent cases go on to become active.)

Speakers – Dr Liz Corbett (LSTM, Malawi) and Professor Ajit Halvani – discussed the new diagnostic assays they are using.

OraQuick over-the-counter HIV test. Now adapted to low-resource settings, this test is more acceptable and avoids stigma of HIV testing clinics. Ninety-nine per cent of Liz Corbett’s study participants in Malawi used it correctly, of whom 18% were found to be HIV positive.
GeneXpert is a genotypic assay detecting TB mutations linked to rifampicin resistance. Faster than a smear, it is used for case finding and identifies rifampicin-resistant TB.
ELIspot, an interferon gamma release assay, was used by Ajit Halvani to address the latency problem. He found that a baby positive with the tuberculin skin test (TST) who is also ELIspot positive is three to four times more likely to progress to active TB by the age of two years.

Diagnosis is not the only problem for TB control; the existing drug regime is long and adherence is a problem. Syeda Hassan, (LSTMH) described how the modulation of CD8 T-cell surface markers NKG2D and PD-1 is being used to monitor the effectiveness of TB treatment, over shorter time periods.

Fragile states (countries affected by conflict or emerging from it)

Dr Chris Whitty spoke of the problems of conducting research programmes in fragile states (of which there are currently considered to be 40 worldwide). He spoke of the resistance of NGOs to research as opposed to action. However, research has been conducted by THET (in Somaliland) and MERLIN (in Liberia). Representatives from these two organizations presented their findings and actively sought future collaboration from delegates.

Following the 2005 conflict, Liberia had just 12 doctors, and maybe 12 midwives, but despite discussions no donor could be found to provide funds for training more. Three years were lost before MERLIN managed to get a programme running. Linda Dowell (MERLIN) linked this missed opportunity to a lack of evidence to present a better case to donors. The organization is now conducting operational research to build such an evidence base.

More details on this issue may found in a report [3] published last year by the Health and Fragile States Network.

References

1. Lucas A (2010). It was the best of times: from local to global health – an autobiography. Ibadan, Bookbuilders Editions Africa [ISBN:978808895-0].

2. Jukes MCH, Draje LJ, Bundy AP (2007). School Health, Nutrition and Education for All: Levelling The Playing Field. Washington DC, World Bank.

3. Health and Fragile States Network (2009). Health Systems Strengthening in Fragile Contexts: A Report on Good Practices & New Approaches. London, Health and Fragile States Network. Available online: http://www.healthandfragilestates.org/index.php?option=com_docman&Itemid=38&gid=54&task=doc_download

Wendie Norris is Editor, Global Health and Tropical Diseases Bulletin, CABI.