Modelled number of AIV cases in wild birds per US state and region, 2006-2008. States are colored based on quintiles so that states that are in the top 20% with respect to the number of AIV cases are colored dark blue and states in the bottom 20% are red-orange. The symbology is adapted from a map of US GDP .
Fuller et al. BMC Infectious Diseases 2010 10:187 doi:10.1186/1471-2334-10-187