University of Albany researchers, Linda Styer and colleagues have recently provided evidence that saliva from a common West Nile virus vector, Culex tarsalis, enhances West Nile virus (WNV) infection in mice. In order to characterize transmission, they assessed WNV in a mouse model. Mice were inoculated with WNV via mosquito and needle and physiological observations were made. In mosquito-bitten mice, they noted a higher degree of early viremia, elevated spread to peripheral tissues, and faster neuroinvasion than the needle-inoculated mice. As the researchers note, this is the first paper that examines the differences in transmission in WNV between one infected mosquito and inoculation by needle.
Linda M. Styer, Pei-Yin Lim, Karen L. Louie, Rebecca G. Albright, Laura D. Kramer, and Kristen A. Bernard
J. Virol. February 2011 85: 1517-1527; published ahead of print December 8, 2010, doi:10.1128/JVI.01112-10