West Nile Virus

The West Nile Virus is a flavivirus that is maintained in nature by way of an enzootic cycle involving birds and mosquitos. The birds act as amplifying hosts while the mosquitos serve as vectors for the virus. Birds that become infected and develop high levels of the virus in their blood pass the infection onto mosquitoes when bit. The infected mosquito will then infect more birds when they bite. When looking at this study, it is important to note that while the West Nile Virus has been detected in at least 326 bird species, this study will only examine 6. The same goes for mosquitoes, as researchers are only interested in examining the competent species in the urban wetlands and adjacent urban residential areas in Central New Jersey. Competency

is the most important factor for virus perpetuation. Observations were conducted in the Middlesex and Union counties from 2009-2010 during the transmission season from June to September. The prominent species to virus perpetuation in this geographic region appear to be the American Robin (avian species) and the Culex Pipiens (mosquito species).

The main objective of this study was to investigate the immediate impacts that different environments had on the spreading of a vector-borne disease; specifically the West Nile Virus. To do so, they examined the distribution of competent and noncompetent species in two dynamically different locations. There is a widely accepted notion that the environment limits the geographic distribution of species because the distribution of a species is dependent on the environment. Urban residential areas reinforce random or regular distribution because they are fairly uniform, while wetlands foster clumped distribution patterns. By studying the interspecific populations in the different environments, researchers hypothesize that urban wetlands will decrease the risk for West Nile Virus and show a decrease in the community presence of competent mosquito and avian species. Based on their previous knowledge of the dilution effect, researchers expect that an increase in diversity will decrease the prevalence of the West Nile Virus. In contrast then, residential urban areas will favor the transmission of the West Nile Virus by supporting those species considered to be competent. They hope their data will provide evidence of a relationship between urban wetland patches and urban disease risk. Studying populations helps to understand and control disease epidemics such as the West Nile Virus.