Natural disasters, such as the recent Indian Ocean tsunami, can have a rapid onset, broad impact, and produce many factors that work synergistically to increase the risk of morbidity and mortality caused by communicable diseases. The primary goal of emergency health interventions is to prevent epidemics and improve deteriorating health conditions among the population affected. Morbidity and mortality due to infectious diseases can be minimized providing these intervention efforts are implemented in a timely and coordinated fashion. This article presents a review of some of the major issues relevant to preparedness and response for natural disasters.