Impacts of Wildlife Infections on Human and Livestock Health with Special Reference to Tanzania: Implications for Protected Area Management1

Human, domestic animal, and wildlife medicine are usually viewed as separate disciplines; however, this distinction is largely irrelevant in the field of epidemiology, because many pathogens are generalists, infecting multiple host species. The majority of human pathogens (62%) also infect animal hosts (Taylor et al. 2001) and nearly half (44%) are also known to infect wildlife (Cleaveland, Laurenson et al. 2001). Similarly, most of the pathogens that have caused recent epidemics in wildlife infect a wide range of hosts (Cleaveland, Hess et al. 2001). A particular concern for conservationists is the ability of these generalist pathogens to spill over from more abundant reservoir hosts (e.g., domestic animals) to infect small, vulnerable wildlife populations (Daszak et al. 2000, Laurenson et al. 2005). In terms of wildlife management and infectious diseases, the focus of concern in recent years has been the direct threat of disease epidemics to the survival and health of endangered wildlife populations. However wildlife infections have farranging impacts that extend beyond these direct disease threats to encompass issues relating to public health, livestock production, and rural livelihoods, each of which has important consequences for wildlife management.