North American Crane Working Group


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Hartup, B.K. Surveillance for west nile virus at the International Crane Foundation 2000-2004. In: Folk, MJ and SA Nesbitt, eds. 2008. Proceedings of the Tenth North American Crane Workshop, Feb. 7-10, 2006, Zacatecas City, Zacatecas, Mexico: North American Crane Working Group. pp. 111-114.


Reproduced by permission of the North American Crane Working Group.


Between 2000 and 2004, serum samples collected annually from captive cranes at the International Crane Foundation (ICF) were analyzed for the presence of West Nile virus (WNV) antibodies using a plaque reduction neutralization test. Eighteen individual cranes representing 8 species were identified with positive titers (geometric mean = 188, range 40 – 1280, n = 29). Whooping cranes (Grus americana) represented the largest proportion of seropositive individuals (33%). Flock seroprevalence increased rapidly in 2003 and 2004 to a peak of 10%, representing a four-fold increase following index cases in 2000. None of the seropositive cranes, however, showed clinical signs consistent with WNV-related disease during the study. The results suggest that exposure of ICF captive cranes to WNV is relatively common and re-affirmed the decision to implement a limited vaccination plan for hatch year whooping cranes believed to be at risk of disease from WNV.