Fight against neglected diseases sets sights on parasites transmitted by livestock

The Schistosomiasis Control Initiative (SCI) will research how efforts to combat the tapeworm infection cysticercosis can be integrated into existing prevention programmes.

Monday 13 December 2010

A group at Imperial College London dedicated to eliminating neglected tropical diseases (NTDs) has received $1.5 million from the Bill & Melinda Gates Foundation to improve control of a disease passed to humans by pigs.

The Schistosomiasis Control Initiative (SCI) will research how efforts to combat the tapeworm infection cysticercosis can be integrated into existing prevention programmes.

The tapeworm Taenia solium, acquired by eating infected pork, resides in the human gut, where it normally causes little harm to the affected person. Cysticercosis is caused by consuming the eggs of the tapeworm, by contamination of food or water with faeces from infected humans. These eggs grow into cysts in the tissues, including the brain, where they can cause severe neurological problems such as epilepsy. The incidence of epilepsy has increased in sub-Saharan Africa as pig keeping and pork consumption have become more widespread in the past decade. A recent study in Tanzania shows that 14 per cent of all epilepsy may be caused by this parasite.

For the last eight years, the SCI has been involved in delivering drugs to treat NTDs across sub-Saharan Africa in mass drug administration programmes. With the support of partners like the World Health Organisation, the SCI and other agencies are increasingly focusing on delivering “rapid impact packages” that target many diseases at once. Zoonotic diseases – those transmitted from animals to humans – are prevalent in poor rural communities but until recently have not been considered for funding as part of the NTD programme. As well as posing a threat to human health, diseases affecting livestock take a considerable toll on the livelihood of poor communities.

Cysticercosis is an obvious candidate for inclusion in control strategies as it is treatable using praziquantel, a low-cost drug given in the rapid impact package to treat the parasitic worm infection schistosomiasis.

Although cysticercosis is easily treated using this drug, some reports have suggested that high doses, like those used to treat schistosomiasis, can increase the risk and severity of seizures in people who have cysts within the brain. However, the risk of side effects when administering the drug in communities where schistosomiasis and cysticercosis coexist has not been assessed systematically.

With the new funding, the SCI and their European and African partners will quantify these risks and develop recommendations for the treatment of the two diseases in affected communities in sub-Saharan Africa. The study will also document the impact of integrated approaches on the burden of disease; as well as the cost-effectiveness of these interventions, taking into account the benefits to livestock production of including zoonotic disease control.

Dr Wendy Harrison

“It’s vitally important that we explore ways to further maximise the impact of existing NTD control programmes , to ensure that we’re using the limited resources available in the most effective way to benefit the most vulnerable communities,” said Dr Wendy Harrison, Deputy Director of the SCI at Imperial College London.

For further information please contact:

Sam Wong
Research Media Officer
Imperial College London
e-mail: sam.wong@imperial.ac.uk
Telephone: +44 (0)207 594 2198
Out of hours duty Press Officer: +44 (0)7803 886 248