Volume 79, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


We investigated the role of the western gray squirrel () as a reservoir host of the Lyme disease spirochete . A survey of 222 western gray squirrels in California showed an overall prevalence of infection of 30%, although at a county level, prevalence of infection ranged from 0% to 50% by polymerase chain reaction. Laboratory trials with wild-caught western gray squirrels indicated that squirrels were competent reservoir hosts of the Lyme disease bacterium and infected up to 86% of feeding larvae. Infections were long-lasting (up to 14 months), which demonstrated that western gray squirrels can maintain trans-seasonally. Non-native eastern gray squirrels () and fox squirrels () were infrequently infected with


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  • Received : 09 Jun 2008
  • Accepted : 05 Jul 2008

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