When West Nile virus first struck New York City in 1999, news of the potentially fatal illness alarmed citizens and public health officials alike, showing that even affluent, urban societies are vulnerable to vector-borne diseases.
Although West Nile virus has been widely studied, there is still little known about how the ecology of mosquito-borne diseases differs between urban and rural areas.
Assistant professor at the University of Georgia Odum School of Ecology John Drake hopes to shed light on these differences with a recently awarded $578,619 grant from the National Science Foundation.
Drake has partnered with the New York Department of Health and Mental Hygiene to obtain data on the prevalence of infected mosquitoes, birds and humans. This data will be used to develop computer models to study differences between West Nile virus in urban versus rural environments. Other goals of the three-year study are to present recommendations for improving New York City’s current mosquito control strategies, and to provide ecologically-based risk maps and calibrated metrics for early warning of disease outbreak. Drake said this would be the start of a long-term study.
“I believe that mosquito population dynamics, which are notoriously complicated, are the key to this study,” said Drake. “Human infection with West Nile virus comes through contact with mosquitoes which get the infection from birds, not humans. And so, there is also an important wildlife-mosquito interaction.”
In America since 1999, West Nile virus has resulted in around 1,000 deaths. And within the last week, the first 2007 fatality from Georgia has been reported, again demonstrating the need for further research on this topic. This serious public health concern has also created a unique opportunity because of the amount of data available.
“Here, for the first time, we have a remarkably complete dataset with which to study the interplay of urbanization and wildlife on the transmission of mosquito-borne disease,” said Drake. “This is a problem that is increasing in importance as urbanization continues to accelerate worldwide.”
Using seven years of outbreak data, Drake and his team will test several hypotheses about vector-borne diseases in the built environment. One idea is that the built structure of urban environments causes diseases to “seep” through the landscape, rather than to spread in waves. Also, Drake will investigate the idea that annual West Nile virus outbreaks correlate with certain patterns in temperature and precipitation. Additionally, Drake aims to determine if a suspected decrease in the severity of the infection in humans relates to the evolution of avirulence in birds.
“In America, we have eliminated malaria and we don’t have a serious problem with dengue fever,” said Drake. “Vector-borne diseases were thought to be a minor issue for the developed world. West Nile virus’ emergence has changed that.”