5.13 Disease and Pathogens
West Nile Virus (WNV) can infect a number of animals, including humans, horses, and birds. It was frst documented in the United States in 1999 and has spread throughout North America. Birds do not normally show any symptoms of WNV infection, but serve as natural reservoirs of the virus. However, some avian species, such as crows, appear to be susceptible to the virus. WNV was frst documented in raptors in the summer of 2002. Since that time, this disease has been diagnosed in Bald Eagles in South Carolina as well as other states. Tere is some evidence that WNV has spread globally in part through transmission by migratory birds introducing the virus to other wildlife and humans (Rappole and Huba´lek 2003; Verhagen et al. 2014) . Avian infuenza (bird fu) is a disease caused by any one of several infuenza subtypes that can afect birds because they are a host reservoir (Alexander 2000; Kilpatrick et al. 2006; Olsen et al. 2006; Munster et al. 2007; Dugan et al. 2008; Verhagen et al. 2014) . Research has documented a high preva- lence for infection in migratory ducks, geese, and swans (order Anseriformes) and in gulls, terns, and shorebirds (order Characdriiformes) (Webster et al. 1992; Alexander 2000; Olsen et al. 2006; Munster et al. 2007) . Te prevalence of infection during fall migration may occur because of the large number of birds that occur in concentrated areas and because there are a higher number of immunologically susceptible young of the year in the population (Webster et al. 1992; Hinshaw et al. 1985; Sharp et al. 1993; Munster et al. 2007) . Surveillance to detect the disease and moni- toring of infected populations to determine impacts is needed before appropriate manage- ment strategies can be developed. 5.13.3 Crayfshes—Anticipated Impacts Relatively little published research is available concerning crayfsh diseases and much of the work is from Australia and Europe. Edgerton et al. (2002) provide a synopsis of crayfsh diseases and pathogens. Most disease agents (viruses, bacteria, etc.) cause only limited impacts to crayfsh (Longshaw 2011) . Disease in freshwater crayfsh can result from abiotic fac- tors such as adverse environmental conditions, poor nutrition, and exposure to waterborne toxicants or biotic factors such as viruses, parasites, or microorganisms (Edgerton et al. 2002) . Crayfsh aquaculture production provides an opportunity to better monitor health status and detect pathogen and disease transmission because population densities allow efcient transfer of disease between individuals. 5.13.4 Mammals—Anticipated Impacts White-nose syndrome (WNS) is a disease of hibernating bats that has spread from the northeastern to the central United States. Since the winter of 2007–2008, millions of insect-eating bats in 25 states and fve Canadian provinces have died from this disease. Te fungus Pseudogymnoascus destructans is known to cause WNS in hibernating and
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2015 NC Wildlife Action Plan
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