Issues in filariasis--a century of enquiry and a century of failure.
A great deal is known about the biology of the filarial parasites infecting man and of their transmission, their clinical manifestations, their treatment and their control but many more people are infected with Bancroftian filariasis and onchocerciasis today than more than 100 years ago when Manson discovered the first live cycle. There has been some success in the control of the Simulium vectors of onchocerciasis in parts of Africa and mass chemotherapy has helped to reduce Bancroftian filariasis in a few Pacific Islands but the main endemic areas have seen no benefit from all the advance in the techniques for controlling these diseases. There is an obvious need for more research to find better tools that are less hazardous to the environment and more acceptable to the affected communities. Fortunately the combined resources of the United Nations Development Programme, the World Bank for Development and the World Health Organization in the setting up of the Special Programme for Research and Training in Tropical Diseases has stimulated a renewed interest in these problems. An obvious area for further research is on the epidemiology of the disease with special emphasis on transmission of the parasites to help with the development of predictive models which might assist in the design and evaluation of control programmes. There is a need for novel approaches to kill the vectors and for the development of more effective and less hazardous drugs. There is a need for immunologists to try to produce vaccines which will help to consolidate other methods of control but of more immediate values will be the production of more specific immunological diagnostic tests and methods for modifying the immunopathology processes caused by the disease and accentuated by treatment. But whatever new tools are produced it is still true to say that control measures will be effective only if there is active cooperation by the affected communities. It is therefore essential that laboratory research is supplemented with research on human behaviour in relation to the transmission of the diseases and also on the acceptability of control measures if we are to avoid the disappointments of many other antiparasitic control campaigns.
D000818:Animals; D005368:Filariasis / Q000453:epidemiology* / Q000517:prevention & control; D005370:Filarioidea; D006801:Humans; D007300:Insect Control; D007303:Insect Vectors; D009032:Mosquito Control; D009855:Onchocerciasis / Q000517:prevention & control; D012106:Research; D014330:Tropical Medicine