Take an indepth look at some of the public health breakthroughs and interventions that have more than doubled life expectancy in developed countries within the past century, and how lack of access to these basic interventions leaves many impoverished countries plagued by preventable diseases.

Although life expectancy remains high in the developed world, in many countries of the developing world life expectancy has actually fallen - primarily due to AIDS, but also famine and the failure to bring proven health interventions to the neediest people. The march to better world health has also been slowed by the emergence of new and potentially devastating diseases, changing natural environments, the mounting problem of drug resistance and the power of local diseases to travel across the globe. In today's global society, there is no haven from any infectious disease.