What are “emerging” infectious diseases?
Infectious diseases whose incidence in humans has increased in the past 2 decades or threatens to increase in the near future have been defined as “emerging.” These diseases, which respect no national boundaries, include: • New infections resulting from changes or evolution of existing organisms • Known infections spreading to new geographic areas or populations • Previously unrecognized infections appearing in areas undergoing ecologic transformation • Old infections reemerging as a result of antimicrobial resistance in known agents or breakdowns in public health measures.
