Volume 93, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



La Crosse virus (LACV), a leading cause of arboviral pediatric encephalitis in the United States, is emerging in Appalachia. Here, we report field and laboratory evidence that suggest LACV may be using mosquitoes as additional vectors in this region. This bunyavirus was detected by reverse-transcriptase polymerase chain reaction in two pools of mosquitoes in southwestern Virginia and in six pools in West Virginia. To assess vector competence, we offered LACV blood meals to field-collected Theobald, L., and (Say). Both species were susceptible to infection. LACV-positive salivary expectorate, indicative of the ability to transmit, was detected in a small proportion of (9%) and (4%) compared with (40%). In a companion study of only, we found that adults derived from nutritionally stressed larvae were significantly more likely to disseminate and transmit LACV. Our results indicate a potential role of spp. in LACV dynamics that should be explored further in endemic areas.


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  • Received : 01 Mar 2014
  • Accepted : 19 May 2015
  • Published online : 02 Sep 2015

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