Rabies and Canine Distemper in an Arctic Fox Population in Alaska

Abstract

Two oil field workers were attacked by a rabid arctic fox (Alopex lagopus) in the Prudhoe Bay oil field (Alaska, USA) prompting officials to reduce the local fox population. Ninetynine foxes were killed during winter 1994. We tested foxes for prevalence of rabies and canine distemper. Exposure to rabies was detected in five of 99 foxes. Of the five, only one fox had rabies virus in neural tissue as determined by the direct fluorescent antibody test. The other four foxes had been exposed to rabies, but had apparently produced antibodies and did not have an active infection. No evidence of canine distemper was detected as determined by the absence of distemper antibodies in serum and distemper virus in neural tissue.

Spatiotemporal distribution of rabies in Arctic foxes in Greenland

“…These are significantly longer intervals than those observed in both North America and Svalbard where cyclicity of 3-5 years has been reported (Tabel et al 1974;Nadin-Davis et al 2008) but comparable with the 6-10 years suggested by Mørk and Prestrud (2004) for arctic populations in general. The link between the cyclic occurrence of rabies outbreaks in Arctic fox populations reported here and in related studies is often reported as being correlated to fox population density, relying in part on cyclic variations in prey abundance, e.g., rodents (Ballard et al 2001;Dalén et al 2005;Norén et al 2011b). When Arctic fox populations peak in numbers, the likelihood of encounters between individuals increases once the foxes disperse (Tabel et al 1974;Mørk and Prestrud 2004;Mørk et al 2011).…”

“…Since the rabies virus may remain infective in frozen carcasses, the etiological agent may be transmitted over extended periods of time. Thus, foxes may become exposed from scavenging on infected carcasses and reinforce a beginning epizootic (Ballard et al 2001;Mørk and Prestrud 2004). …”

Arctic Foxes, Lemmings, and Canada Goose Nest Survival at Cape Churchill, Manitoba

“…However, if alternative prey, particularly nesting birds, is not abundant when lemming abundance decreases, foxes may not breed and become nomadic or substantially increase the size of their home range (Wrigley and Hatch 1976, Eberhardt et al 1983, Eide et al 2004). The extent of increased arctic fox mortality or emigration and the magnitude of a decline in fox abundance, following a lemming peak, likely depends on timing of the lemming population crash (Tannerfeldt et al 1994, Angerbjörn et al 1999, abundance of alternative food resources (natural [Roth 2003] or man-made [Eberhardt et al 1982[Eberhardt et al , 1983), prevalence of disease (Kaplan 1985, Ballard et al 2001, and how foxes respond to these factors.…”

Home Range, Body Condition, and Survival of Rehabilitated Raccoons (Procyon lotor) During Their First Winter

“…During an outbreak, rehabilitated individuals, having been vaccinated, should show increased survival compared with wild, unprotected individuals. In addition, outbreaks of rabies or canine distemper are associated with high population densities (Ballard, Follman, Ritter, Robards, & Cronin, 2001;Hoff, Bigler, Proctor, & Stallings, 1974), and the addition of rehabilitated individuals to a wild population may contribute to a disease outbreak. However, if the rehabilitated individuals have been vaccinated, then their addition should have no effect on disease transmission and may even act to reduce disease transmission.…”