MULTIPARASITE COMMUNITIES IN ANIMALS AND HUMANS - FREQUENCY, STRUCTURE AND PATHOGENIC SIGNIFICANCE

Individual humans and animals are subject to infection by a variety of parasites (broadly defined to include viruses, bacteria and other non -protozoan microparasites) at any one time. Multiple parasite infectio ns occur frequently in populations of wild animals as well as in human s from developing countries. In some species and regions, hosts with m ultiple infections are more common than hosts with either no infection or a single infection. Studies, predominantly on animals, show that a wide variety of environmental and host-dependent factors can influenc e the structure and dynamics of the communities of parasites that make up these multiple infections. In addition, synergistic and competitiv e interactions can occur between parasite species, which can influence the likelihood of their successful transmission to other hosts and in crease or decrease their overall pathogenic impact. This review summar ises aspects of our current knowledge on the frequency of multiparasit e infections, the factors which influence them, and their pathogenic s ignificance. (C) 1998 Australian Society for Parasitology. Published b y Elsevier Science Ltd.