Parasitic diseases lymphatic filariasis

One likely reason for the prevalence of helminths is their undoubted ability to down-regulate the host immune system at both the antigen-specific and polyclonal levels [3], In many chronic diseases, such as schistosomiasis and lymphatic filariasis, peripheral blood T cells show dramatically impaired parasite antigen-specific responsiveness [4], as discussed in more detail below. Moreover, from early reports of immunosuppression in animal models of infection, to studies in Africa linking vaccine failure to heavy helminth infection, there is clear evidence that infections can diminish reactivity to bystander antigens, particularly with increasing intensity of... 

Our perspective is thus one of general significance to chronic infection, as well as one that will provide specific pathways to novel treatments of human schistosomiasis, and lymphatic filariasis. These two diseases represent a massive public health problem with 300 million people infected in the world today. Intervention by ablating parasite-specific Tregs in these patients will solve the specific problems of schistosomiasis and filarial diseases, while at the same time proving a principle which will be applicable to chronic infections in general. 

Wuchereria bancrofti, a mosquito-transmitted parasite, is the major cause of human lymphatic filariasis in tropic areas. Current estimates suggest that about 120 million people are infected. Infection often leads to microfilaremia without clinical manifestations. The most common clinical presentation of this disease are asymptomatic microfilaremia, filarial fever, and lymphatic obstruction. Ivermectin rapidly reduces microfilaremia concentration in peripheral blood and may inhibit larval development in mosquitoes. Because the drug does not kill adult worms, microfilaremia concentration begins to increase gradually 3-12 months after treatment. 

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