Infection!

Historically, the biggest threat to human life and health has been infectious disease. The tremendous gains in the developed world in the area of life expectancy have been due in large part to advances in public health, traditionally focused on infectious disease prevention. Those advances have yet to be realized in the developing world, where in Zambia, for example, average life expectancy is the same as it was in the U.S. in 1900 (47 years). Unfortunately, public health and disease prevention almost always take a back seat (or the rear bumper) to economic development. This seems perverse in that such development SHOULD be accompanied by quality of life interventions, or what is the money for? Even in the developed world we have seen an erosion in the quality of basic public health as we have relied more on "cures". The best way to deal with an infection is to never get one at all.