Diseases that need new drugs: Need of the hour
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Cholera is an important cause of mortality, and several complex factors determine its re-emergence. Both virulent and avirulent strains of these zoonotic bacteria are maintained in the environment and are rapidly evolving in association with phyto- and zooplankton, algae and crustaceans. These environmental strains seem to act as reservoirs for human virulence genes (genes for the phage-encoded cholera toxin and the toxin-coregulated pilus (TCP) factor for attachment), and to undergo gene transfer events that lead to new strains with more virulence gene combinations. These result in periodic cholera emergences causing epidemics and pandemics (Faruque & Nair, 2002). Thus, although the disease cholera appeared to be clinically and epidemiologically stable since the third pandemic in the 1840s, modern evidence suggests that such apparent stability masks aggressive bacterial evolution in complex natural environments.
Neglected diseases (DNDi): Matching needs and opportunities Neglected diseases such as leishmaniasis, trypanosomiasis, Chagas disease and malaria have a devastating impact on the world's poor. These treatable, tropical diseases have been progressively marginalized by research programme decision makers. Unfortunately, people suffering from these diseases do not constitute a market lucrative enough to attract investment in research and development for new drugs. For decades if not centuries, Malaria is a major killer, and is still killing between one and two million people a year. The victims are mostly developing-country babies, particularly African babies. Drugs for Neglected Diseases Initiative (DNDi) are addressing this lack of new, improved drugs for neglected patients with an alternative model of research and development. This model matches patients' needs with gaps identified in the drug development pipeline. Parasitic infections are a major global health problem, particularly for lessdeveloped nations, where it causes a substantial economic burden. The global prevalence of parasitic infections is more than 50% due to factors like population, poverty and pollution, that leads to poor sanitation and health education, inadequate control of vector, infection and agricultural waste, global travel, population migration, military operation and development of resistant parasitic and vectors to the existing drugs or chemicals. Most of these infections are neglected because their effects on human health are more subtle, except malaria that causes high morbidity and mortality without treatment. Chemotherapy remains the single most effective, efficient and inexpensive method to control most of the parasitic infections despite encouraging progress in identifying promising molecular targets for vaccines. The global effort of last 50 years is unable to provide safe and effective drugs for the treatment of serious parasitic