| Abstract |
The pig tapeworm is the leading cause of preventable epilepsy worldwide. Adult tapeworms live in the human small intestine, eggs are passed in faeces and if eaten by pigs will develop into larval cysts in muscles. Eating cysts in under-cooked pork completes the life-cycle in humans. However, ingested eggs can also develop into cysts in humans, and if cysts develop in the brain, they can cause neurocysticercosis, with epilepsy the most important symptom. The prevalence of epilepsy is high in low and middle income countries, and around a third of epilepsy cases in endemic areas are thought to be due to tapeworm infection, where poor sanitation enables exposure of pigs and people to infective eggs in human faeces. The burden of disease is particularly high in sub-Saharan Africa, and is likely to increase as pig production and pork consumption is increasing rapidly. A number of methods are have recently become available to control of pig tapeworm infection. This includes effective drugs to treat pigs and people, and a newly developed vaccine that protects pigs from infection. Using these methods it has been shown to be possible to control the disease in Peru in an intensive control programme. There is now a need to study how best to use these methods to sustainably control infection in African countries such as Rwanda. Rwanda is a small but densely populated country, mostly engaged in subsistence agriculture, with a very low per capita GDP. There has been significant investment in agriculture, including pig introduction, and the pig population has increased dramatically to more than 1 million in the last decade as demand for pork increases. Most pig production is small scale, and is an important source of income for smallholders, but these production methods are associated with a high risk of cysticercosis in neighbouring countries. Cysticercosis is also a large economic cost for pig production, as infection reduces the value of the meat by up to 50%. There is a clear need for new control initiatives, and Rwanda provides an excellent opportunity, with small size and relatively strong institutions and infrastructure. The prevalence of epilepsy in Rwanda is high, with a severe social stigma attached to the disease. However, there is almost no detailed information available on the prevalence of infection in pigs and humans in Rwanda, nor on the economics of pig production in the country. Our objectives are to collect these essential data on pig production methods and economics, the prevalence of infection in pork entering the food chain and in pigs and humans across the country, and determine the risk factors for infection in humans and pigs. We will then use these results, and inputs from important stakeholders, to develop a national country strategy. This will include developing economic models for investment in disease control in pigs, such as new markets for disease-free pork, and exploring how private sector business and public sector disease control efforts can be effectively combined. Finally, we will establish a partnership between national government, scientists and disease control experts, to plan the implementation of disease control. The outcomes of the project will be the first assessment of the importance of cysticercosis in Rwanda for human health and agricultural production, and the development of a national plan for disease control. To achieve these outcomes, we will establish a new collaboration between UK and Rwandan investigators to build local capacity in parasitological research. |
