West Nile virus: a growing concern?
J. Clin. Invest. L. Hannah Gould, et al. 113:1102 doi:10.1172/JCI21623 [Go to this article.]

Figure 1
WNV activity in North America as of January 2004. Shading represents areas in which virus activity has been recorded. 1, Chihuahua; 2, Coahuila; 3, Tamaulipas; 4, Veracruz; 5, Tabasco; 6, Yucatan.