Zoonotic and vector-borne parasites are important preventable risk factors for epilepsy. Three parasitic infections — cerebral malaria, Taenia solium cysticercosis and onchocerciasis — have an established association with epilepsy. Parasitoses are widely prevalent in low-income and middle-income countries, which are home to 80% of the people with epilepsy in the world. Once a parasitic infection has taken hold in the brain, therapeutic measures do not seem to influence the development of epilepsy in the long term. Consequently, strategies to control, eliminate and eradicate parasites represent the most feasible way to reduce the epilepsy burden at present. The elucidation of immune mechanisms underpinning the parasitic infections, some of which are parasite-specific, opens up new therapeutic possibilities. In this Review, we explore the pathophysiological basis of the link between parasitic infections and epilepsy, and we consider preventive and therapeutic approaches to reduce the burden of epilepsy attributable to parasitic disorders. We conclude that a concerted approach involving medical, veterinary, parasitological and ecological experts, backed by robust political support and sustainable funding, is the key to reducing this burden.
The preventable risk factors for epilepsy include CNS infections, among which parasitic disorders constitute an important subgroup.
Parasitic disorders that have been linked to epilepsy, including cerebral malaria, Taenia solium neurocysticercosis, onchocerciasis and toxocariasis, are especially prevalent in resource-limited settings.
Effective treatments are in place for many parasitic disorders, but the long-term impact of these treatments on the development of epilepsy has not been assessed.
Currently, primary prevention — that is, control, elimination and eradication of parasitic disorders — remains the only viable approach to reduce the epilepsy burden associated with these conditions.
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This work was carried out at the National Institute for Health Research University College London Hospitals Biomedical Research Centre, which receives a proportion of funding from the UK Department of Health’s Research Centres funding scheme. S.A.A. is a Commonwealth Scholar and is funded by the UK Department of International Development. J.W.S. receives research support from the Dr Marvin Weil Epilepsy Research Fund, from the UK Epilepsy Society and the Christelijke Vereniging voor de Verpleging van Lijders aan Epilepsie, Netherlands.
J.W.S. has received personal fees from Eisai, UCB and Zogenix and grants from UCB and GW Pharmaceuticals outside the submitted work. His current position is endowed by the Epilepsy Society. The other authors declare no competing interests.
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Singh, G., Angwafor, S.A., Njamnshi, A.K. et al. Zoonotic and vector-borne parasites and epilepsy in low-income and middle-income countries. Nat Rev Neurol 16, 333–345 (2020). https://doi.org/10.1038/s41582-020-0361-3