Emerging infectious diseases: A cause for concern

As the twenty-first century begins it becomes increasingly apparent that th e twentieth century, which opened with the promise of the eradication of mo st infectious diseases, closed with the specter of the reemergence of many deadly infectious diseases that have a rapidly increasing incidence and geo graphic range. Equally ii not more alarming is the appearance of new infect ious diseases that have become major sources of morbidity and mortality. Am ong recent examples are HIV/AIDS, hantavirus pulmonary syndrome, Lyme disea se, hemolytic uremic syndrome (caused by a strain of Escherichia coli), Rif t Valley fever, Dengue hemorrhagic fever, malaria, cryptosporidiosis, and s chistosomiasis. The reasons for this situation are easily identified in som e cases as associated with treatment modalities (permissive use of antibiot ics), the industrial use of antibiotics, demographic changes, societal beha vior patterns, changes in ecology global warming, the inability to deliver minimal health care and the neglect of well-established public health prior ities. In addition is the :emergence of diseases of another type. We have b egun to characterize the potential microbial etiology of what has historica lly been referred to as chronic diseases.