THURSDAY, Oct. 20, 2011 (HealthDay News) -- Robins play a major role in the transmission of West Nile virus because the bird is a favorite meal for mosquitoes that carry the virus, new research finds.
West Nile virus first appeared in North America in New York City in 1999 and is now well established throughout North and South America. Although the virus can infect many different types of animals, a few key species of birds and mosquitoes play the major role in transmission of the virus, said Marm Kilpatrick, a biologist at the University of California, Santa Cruz, said in a university news release.
"We now know that in any given location, only one or two species of mosquitoes play a big role, and only a handful of birds appear to be important in overall transmission of the virus," Kilpatrick said.
The robin is one of those key bird species and plays such a major role in West Nile virus transmission that Kilpatrick calls robins "super-spreaders" of the virus. This is because mosquitoes that transmit the virus seem to prefer robins over other, more abundant species of bird such as house sparrows.
"Robins are more important in transmission than their abundance alone would suggest," Kilpatrick said. "The peculiar feeding habits of the vectors play a really important role in transmission, and this idea applies to many different diseases."
Kilpatrick reviewed a decade of research on the ecology and evolution of the West Nile virus. The paper appears in the Oct. 21 issue of the journal Science.
Learning more about the spread of West Nile virus could help public health officials when they're faced with other introduced diseases in the future, experts noted in the news release.
"The spread of disease-causing organisms is likely to only increase in the coming years," Sam Scheiner, director of the Evolution and Ecology of Infectious Diseases program at the U.S. National Science Foundation, said in the news release.
"West Nile virus has provided a test of our ability to respond to such spread. This research shows that predicting disease incidence in humans and other animals is more complex than first imagined, but that greater understanding of such complexities is possible -- knowledge that can be applied to the next threat," Scheiner explained.
The U.S. Centers for Disease Control and Prevention has more about West Nile virus.