Before there was an understanding of infectious disease, few weapons were available to fight it. Disease Warriors chronicles the groundbreaking work of early researchers, such as the famed scientist Louis Pasteur, who unmasked germs as the source of illness. Pasteur went on to develop a rabies vaccine — a great scientific triumph. Today, vaccines have made huge strides against epidemics, conquering smallpox and bringing the global eradication of polio within reach. But the world still faces major challenges in getting basic vaccines to those who still need them, and in creating new ones to combat modern nemeses, like AIDS.

It's difficult to imagine a world without medicines — and yet, before the twentieth century there weren't any. The discovery of the very first antibiotic, penicillin, and the subsequent development of more "wonder drugs" transformed the face of modern medicine. Rise of the Superbugs chronicles these historic successes, as well as the growing threat posed by new strains of germs, such as tuberculosis and staph, that are resistant to our best antibiotics. Are our strongest medicines becoming obsolete, and can we develop new drugs in time to replace them?

At the dawn of the 21st century, we can prevent, treat or cure most of the deadliest diseases known to humankind — and yet millions die needlessly every year because the benefits of modern medicine and public health fail to reach them. What are the obstacles to providing care to populations in need? From the villages of the Gambia to the cities and towns of Thailand, from the sun-scorched refugee camps of Chad to the teeming streets of Bangladesh — this episode chronicles innovative health programs and charismatic leaders who, against all odds, are Delivering the Goods to millions of individuals — and inspiring a new vision for the future of global health.

Since the plague killed millions of Europeans in the Middle Ages, vector-borne diseases — those that rely on insects and animals to spread infectious agents — have posed a serious threat to public health. Today, the most dangerous vector on earth is the mosquito. From malaria to yellow fever to West Nile virus, mosquito-borne diseases continue to threaten the health of millions around the world. Deadly Messengers recounts the stories of heroic scientists and health workers who battled against the mosquito, and examines current efforts to control dangerous and spreading vector-borne diseases.

Ever since sailors noticed that scurvy could be prevented with citrus fruits, it has been clear that illness could be caused by a lack of certain nutrients. While nutrient-enriched products have reduced diseases caused by vitamin deficiency in the developed countries, the problem continues to plague the developing world. And many in poorer countries suffer from the twin problems of poor nutrition and unsafe water, which create a disease burden that is almost unbearable. Back to the Basics explores the connection between health and the essential requirements that so many people take for granted. It also examines how an overabundance of nutrition — in the form of over-consumption — is causing an epidemic of obesity that is spreading across the globe.

During the past 100 years, life expectancy more than doubled in developed countries. In the last few decades, however, thirty new infectious diseases have emerged and one of them — AIDS — is becoming perhaps the most devastating epidemic in history. New diseases travel the globe with unprecedented rapidity, and older killers that once seemed controllable are roaring back with a vengeance. How Safe Are We? examines the most critical threats we face today — including avian flu — and the pressing need to strengthen global public health systems.