Population mobility and infectious diseases: the diminishing impact of classical infectious diseases and new approaches for the 21st century.

In an increasingly globalized world, rapid population mobility and migration is reducing the differences in infectious disease epidemiology between regions of the world. The movement and relocation of populations between locations where the prevalence and incidence of infections are markedly different poses current and future challenges to those involved in clinical infectious diseases and public health program management. Historically, international attention has focused on the screening and treatment of acute infections of epidemic potential, but, as immigration significantly changes the demography of many nations, chronic infections will require increased attention. In countries with large mobile populations, the population-based burden of infections with long latency periods or significant noninfectious sequelae will make up an increasing amount of the infectious disease caseload and will require more-modern approaches than the traditional screening of arrivals. The globalization of chronic infectious disease epidemiology will require corresponding development of integrated programs to anticipate and manage these diseases in response to an increasingly mobile patient population.