Neglected tropical diseases: elimination and eradication.

The term neglected tropical diseases (NTDs) describes a disparate group of diseases which affect populations living in poverty and are important causes of morbidity and mortality worldwide. Global programmes for the control of NTDs benefit large-scale donations made by pharmaceutical companies. A number of NTDs have internationally agreed targets for their control, elimination and eradication. Eradication is defined as the permanent reduction to zero of the worldwide incidence of infection. Elimination is defined as the reduction to zero of the incidence of infection in a specified geographic area. Considerable progress has been made towards elimination and eradication of some NTDs but unexpected new challenges have emerged which threaten the eventual achievement of these goals.