Marm Kilpatrick, a researcher at UC Santa Cruz, has been studying patterns in West Nile transmission and has identified robins as being particularly influential in the spread of West Nile virus. Although a variety of species can be infected with the virus, in a given location, the majority of viral transmission was found to be dependent on a few key species of mosquitoes and birds - one of those being robins. Apparently, mosquitoes prefer feeding upon robins to other species of birds.
I feel like this information could be particularly useful in studying viral epidemiology when examining changing environments. It's important to keep an entire ecosystem in mind when examining either natural or human-induced changes on an environment, but knowing the key species that could in turn impact infectious disease is especially important in measuring the effect that these changes will have on human populations.