Despite medical advances that have produced hundreds of drugs that are safe and effective against bacteria, viruses, fungi and parasites, infectious diseases are still a major cause of death, disability and social and economic upheaval for millions around the world. More than 90 percent of the deaths from infectious diseases worldwide are caused by only a handful of diseases.

Beyond the general ecology of many developing countries, a number of social and economic factors contribute to the high rates of infectious disease. Poverty, lack of access to health care, antibiotic resistance, evolving human migration patterns, new infectious agents, and changing environmental and development activities all contribute to the expanding impact of infectious diseases.