These maps reflect information for the 2004 West Nile Virus reporting season that has been submitted and verified to CDC through the week of April 30, 2005. These are the final USGS West Nile maps for the 2004 season.

These maps reflect information for the 2003 West Nile Virus reporting season that has been submitted and verified to CDC through the week of April 9, 2004. These are the final USGS West Nile maps for the 2003 season.

These maps reflect information for the 2002 West Nile Virus reporting season that has been submitted and verified to CDC through the week of April 22, 2003. These are the final USGS West Nile maps for the 2002 season.

These maps reflect the final reported and verified information from the 2001 West Nile Virus Surveillance Database. The database includes events through December 28, 2001.