Volume 79, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Eastern gray squirrels () have shown high West Nile virus (WNV) seroprevalence, and WNV infection has been suggested as a cause of morbidity and mortality in this species. We experimentally infected nine eastern gray squirrels with WNV to determine the clinical effects of infection and to assess their potential role as amplifying hosts. We observed no morbidity or mortality attributable to WNV infection, but lesions were apparent in several organs. We detected mean viremias of 10 and 10 plaque-forming units (PFU)/mL on days 3 and 4 post-infection (DPI) and estimated that ~2.1% of feeding on squirrels during 1–5 DPI would become infectious. Thus, are unlikely to be important amplifying hosts and may instead dampen the intensity of transmission in most host communities. The low viremias and lack of mortality observed in suggest that they may be useful as sentinels of spillover from the enzootic amplification cycle.


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  • Received : 10 Mar 2008
  • Accepted : 02 Jun 2008

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