Environmental and Social Influences on Infectious Diseases

Abstract

The contemporary social and environmental influences on infectious diseases can be better understood by exploring the long historical procession of disease risks, as human culture has evolved from early hunter-gatherer days. The main features of today's world that contribute to the increased probability of emergence and spread of infectious diseases in humans are shown in a table. Social-cultural factors are of great importance in influencing the contemporary changes in patterns of new and spreading infectious disease. Further, social circumstances are also a basic determinant of susceptibility to infection. The emergence of a zoonotic disease in humans requires a novel type or amount of contact between humans and the existing animal reservoir for the infectious agent. It is necessary to understand the particular circumstances that favor the “emergence” of bacteria, viruses, protozoa, and prions in response to these social and environmental changes. It is also forcibly reminded of the unpredictability and irrepressibility of infectious disease mobility and mutability by the devastating ongoing pandemic of HIV/AIDS since it emerged in the 1980s. Many infectious diseases are sensitive to climatic conditions, particularly insect-borne infections and infections that are spread person-to-person via contaminated food and water. Natural climatic variations and events can influence infectious disease emergence. Each of these infectious diseases is maintained, at least in part, in wild birds. Several recent scientific reports suggest that recent climate change has already begun to influence some infectious diseases.