Intestinal parasites.

Although safe and efficacious broad-spectrum antiparasitic drugs have been developed, their availability for use in mass-treatment programs and for individual treatment worldwide can be limited by economic resources, existing manufacturing and distribution networks, and national regulations. Increasing population density, environmental pollution with human waste products, and global migration patterns will continue to promote transmission of human intestinal parasites in the foreseeable future because untreated or incompletely treated infected individuals can serve as roving reservoirs of infection for long-lived parasites. Asking primary care patients about possible geographic exposures and activities associated with an increased likelihood of intestinal parasite infection is an important part of the medical history. Many intestinal parasites can be treated effectively with oral medications, and treatment relatively early in the course of infection may prevent development of disease associated with chronic infections.