From PK-PD to COUNTDOWN: Multidisciplinary studies on schistosomiasis in Africa

On Friday the 20 November Russell Stothard will be presenting at the London School of Hygiene and Tropical Medicine in one of the regular seminars of the Department of Immunology and Infection.

Russell will discuss contemporary research on schistosomiasis and draw attention to the pioneering early role of the London School’s first helminthologist, Robert Leiper, who uncovered the lifecycle of the African schistosome 100 years ago. Russell’s recent work in Uganda has drawn attention to a significant burden of disease in pre-school children, and he will present the case as to why expanded access to praziquantel treatment is needed now. Ongoing pharmacokinetic and pharmacodynamic (PK-PD) suggests that higher doses of praziquantel may be required.  Russ will close showing how implementation research, as framed within the DFID-funded COUNTDOWN consortium, is playing an important role in accelerating towards WHO 2020 NTD targets.

Update from Coalition for Operational Research on Neglected Tropical Diseases and the American Society of Tropical Medicine and Hygiene conferences

By Russell Stothard

Several COUNTDOWN staff travelled to Philadelphia, USA to attend two important events, the meetings of the COR-NTD 22-23rd October and the ASTMH 25-29th October.

The COR-NTD meeting brought together over 350 international delegates interested in research and control activities surrounding neglected tropical diseases (NTDs). In a combination of plenary lectures, panel discussions and themed break-out sessions, the state-of-the-art and future funding landscape was assessed and explored. COUNTDOWN researchers played significant roles at COR-NTD by organising two break-out sessions dedicated to addressing gender-related inequities and expanded access to praziquantel/albendazole.

The equity session was organised by Margaret Gyapong and Samantha Page, and chaired by Charles MacKenzie, and I was delighted that Camilla Ducker, of DFID joined the panel. The session drew attention to several current gender-related inequities that ranged from a variety of levels from the international to the community. Even within this audience there was confusion over the formal use of various de-worming drugs in pregnancy, and we simply don’t know the current gender composition of community health workers. Better knowledge of each has significant bearing on the management of several NTDs in women and exploration of new drug delivery channels that specific provide access to currently overlooked groups.

This theme of control of NTDs in pregnancy was again picked up in the session I organised with David Addiss where we discussed expanded access to praziquantel and albendazole in groups outside that of school-aged children. In the first presentation, Evan Secor did a remarkable job in setting the ground so well where key gaps were. If these gaps are not filled soon then several WHO 2020 targets for schistosomiasis and soil-transmitted helminthiasis will not be met. The WHO desk officer for schistosomiasis Amadou Garba, highlighted a pertinent point that many women will still have female genital schistosomiasis and will have continued illness unless praziquantel campaigns can be effectively scaled-up. Future COUNTDOWN work was discussed by Sam Wanji identifying current access gaps in Cameroon. Moving towards biannual treatment with praziquantel is needed and Dan Colley (the Director of SCORE) discussed this benefit with regard to our current understanding of disease-inflammation and morbidity.

slide for the astmh blog

Concerning soil-transmitted helminthiasis, recent results from the TUMIKIA project  were highlighted which also have some bearings on the recent #wormwars debate on twitter. Similarly, Hugo Turner and Deirdre Hollingsworth drew attention to a clutch of NTD modelling papers – “Quantitative analysis of strategies to achieve the 2020 goals for neglected tropical diseases: where are we now?”. Here expanded access to treatment was discussed in relation to future reduction of parasite transmission, and hopefully COUNTDOWN will pave the way forward on how to do it.

Other disease-specific highlights at the COR-NTD meeting included evidence that triple combination therapy of ivermectin/albendazole/DEC could more sharply curtail microfilaraemia and transmission of lymphatic filariasis. In addition, a new initiative concerning research on soil-transmitted helminthiasis was announced by Judd Walson as to be supported by Bill & Melinda Gates Foundation and based at the Natural History Museum, London.

During the following week, there was a much larger attendance at the ASTMH. I was happy to attend a WHO and USAID chaired symposium on “Global NTD elimination: the spring towards the 2020 goals – five years out”. Perspectives from major health stakeholder were aired. It is very clear that a significant future bottleneck will be in disease diagnostics and NTD surveillance. Increasing access to state-of-the-art diagnostics is needed now and will be critical to mobilise the diagnostic sector in a similar manner in which industrial philanthropy within the pharmaceutical sector has taken place with drug donations. To identify these diagnostic gaps and encourage actions, COUNTDOWN is set to explore the best interface and find synergy with polio-disease surveillance systems, so watch this space.