Eliminating soil-transmitted parasitic worms: the DeWorm3 challenge | Sustainability

by Hannah Wolley, Museum Development Intern

As someone with two science degrees and a fascination for the unusual I was intrigued, when I found out that the Museum is a world leader in the research of Neglected Tropical Diseases (NTDs).

NTDs are a group of parasitic and bacterial infections that affect over 1 billion people worldwide. Infection can lead to disabling chronic conditions, delayed and cognitive development. Children are predominantly affected and impacted as they are more likely to come into contact with the parasites.

The research at the Museum has in recent years mainly focused on schistosomiasis (also known as Bilharzia), a debilitating disease caused by schistosome blood flukes that are picked up from contaminated fresh water – freshwater snails are hosts for part of the life cycle.

However, Museum research is now radically expanding to include major work on a group of NTDs called Soil Transmitted Helminths (STH) and they have recently launched DeWorm3. Aimed at demonstrating the feasibility of using integrated platforms to interrupt the transmission of STH, DeWorm3 is funded by the Bill and Melinda Gates Foundation.

Dr Tim Littlewood is the Head of Life Sciences and in charge of overseeing the project at the Museum and explained to me the importance and significance of this research.

‘If you are reducing morbidity and mortality and you’ve got more people going to school, more people being able to do their normal daily things because they are less ill, then development rides on the back of that; it means better education, for everybody’

Investing in controlling and eliminating NTDs is directly related to the development of the economic and social development of affected areas and this project is particularly exciting because it is based on mathematical models that simulate disease patterns and the effect of treatment. These mathematical models are built on existing data, associated with mass drug administration.

Drug delivery at the moment is provided free by the major pharmaceutical industries such as GSK, Johnson and Johnson and Mectizan and because there are over 1.1 billion people estimated to be directly affected by these diseases, getting the drugs to those affected is neither easy or cheap.

Tim told me, ‘The theory is that through the right application of the mass drug administration the transmissions of those STH can be interrupted so you break the life cycle. That provides an opportunity to remove them from an environment such that they are effectively eliminated – in which case you can stop your mass drug administration.’

These particular mathematical models are new. What makes the approach novel is that as the trials go ahead and as the data collected are analysed to give information on disease frequency and parasite load, the results are then fed back to improve the model and to make it a more accurate reflection of the real world.

This means that it is a self-correcting model. When the results deviate from it, the model itself is rejigged and this in turn directly affects the methodology. So instead of the usual research model of ‘we want to do this, please may we have some money come back and talk to us in five years’ time’ its ‘we want to do this, we believe these are the best ways to test the model please watch us constantly and use the results’. The hope is that the wider public health and disease control community sees how the trial is doing and whether it is on course for breaking transmission. The advantage of having the project under that spotlight in this way is that it will hopefully get the NTD community and governments and policy advisors to engage with the project from the outset and prepare to apply its findings.

The message, Tim told me, is ‘come and have a look at this and see if this assists you in your on-going mass NTD treatment programmes. And whether you also want to be part of this self-correcting model implementation programme’.  Tim and his colleagues hope to see a growing community building on the original trials so that the models are stronger and the data are more unified. The more data that are collected, the better the model becomes.

The idea from a broader perspective with NTDs is that if the DeWorm3 group can work in that kind of self-correcting way they will improve their models swiftly and reach the end game of elimination much more quickly. The challenges for that end game are  substantial involving policy, public health, science, economics and more.

The international London Declaration on NTDs brought together governments, scientists, medics and charities to set goals to control the spread and infections rates of STHs by 2020, as well as have eliminated several NTDs by then.

Realistically its 2016 now, can they meet these goals? Watching the progress of DeWorm3 should give us a good idea of whether this is possible