Emergence of Diseases From Wildlife Reservoirs

Abstract

Interest in the epidemiology of emerging diseases of humans and livestock as they relate to wildlife has increased greatly over the past several decades. Many factors, most anthropogenic, have facilitated the emergence of diseases from wildlife. Some livestock diseases have ''spilled over'' to wildlife and then ''spilled back'' to livestock. When a population is exposed to an infectious agent, depending on an interaction of factors involving the host, agent, and environment, the population may be resistant to infection or may become a dead-end host, a spillover host, or a maintenance host. Each exposure is unique; the same species of host and agent may respond differently in different situations. Management actions that affect the environment and behavior of a potential host animal may allow the emergence of a new or as yet undetected disease. There are many barriers in preventing, detecting, monitoring and managing wildlife diseases. These may include political and legal hurdles, lack of knowledge about many diseases of wildlife, the absence of basic data on wildlife populations, difficulties with surveillance, and logistical constraints. Increasing interaction between wildlife and humans or domestic animals may lead to disease emergence and require innovative methods and strategies for disease surveillance and management in wildlife.

The relationship between physiological stress and wildlife disease: consequences for health and conservation

“…Rhyan and Spraker (2010) described how mounting stressors may profoundly change disease-transmission cycles using the analogy of 'adding bags of sand to a rowboat until it sinks'. Understanding the dynamics of stress and disease in wildlife will help us keep healthy biological systems 'afloat' by identifying novel management targets and assisting priority setting and policy decisions.…”

Characteristics of white-tailed deer visits to cattle farms: implications for disease transmission at the wildlife–livestock interface

“…3 Mean (±SE) number of visits by white-tailed deer to a farms, b yards, and c cattle-use areas throughout a year. The months of July and September had reduced sampling frequency common disease management tools such as population reduction or vaccination are often controversial, resource intense, or nonspecific (Rhyan and Spraker 2010) and may not be appropriate in all situations. Methods to identify high-risk deer for selective culling or vaccination are limited and have been identified as a critical gap in research (Sweeney and Miller 2010).…”

Six recommendations for improving monitoring of diseases shared with wildlife: examples regarding mycobacterial infections in Spain

“…Data and samples gathered can be used for detecting emerging diseases (Rhyan and Spraker 2010) and in retrospective studies (Oleaga et al 2008;Ruiz-Fons et al 2008). Ideally, monitoring information should integrate data on the risk factors determining the pathogen epidemiology, such as host abundance and distribution, as they can inform us on potential disease spread in a given spatial or temporal frame.…”