Wildlife disease

Disease is described as a decrease in performance of normal functions of an individual caused by many factors, which is not limited to infectious agents.^[1] Furthermore, wildlife disease is a disease when one of the hosts includes a wildlife species. In many cases, wildlife hosts can act as a reservoir of diseases that spillover into domestic animals, people and other species. Wildlife diseases spread through both direct contact between two individual animals or indirectly through the environment. Additionally, human industry has created the possibility for cross-species transmission through the wildlife trade.Furthermore, there are many relationships that must be considered when discussing wildlife disease, which are represented through the Epidemiological Triad Model.^[2] This model describes the relationship between a pathogen, host and the environment. There are many routes to infection of a susceptible host by a pathogen, but when the host becomes infected that host now has the potential to infect other hosts. Whereas, environmental factors affect pathogen persistence and spread through host movement and interactions with other species.^[2] An example to apply to the ecological triad is Lyme disease, where changes in environment have changed the distribution of Lyme disease and its vector, the Ixodes tick.^[3] The recent increase in wildlife disease occurrences is cause for concern among conservationists, as many vulnerable species do not have the population to recover from devastating disease outbreaks.