West Nile Virus Research

Much work has been done to understand the public health effects of this disease since its arrival in New York City, but less understood are the ways WNV is affecting wildlife populations, particularly wild birds, a major reservoir of the virus. The NWHC is working on three new ambitious research studies to investigate WNV in wild birds.

The first involves the Hawaiian Amakihi. Amakihi are part of a family of birds known as Hawaiian Honeycreepers, which were a wildly diverse and successful avian species before the arrival of humans on the islands exposed them to invasive diseases and species. Today, at least 12 different species of Honeycreeper are listed as endangered. The Center’s Amakihi study aims to help assess the potential effect WNV could have if it reaches Hawaii . Scientists are testing the birds’ susceptibility to WNV infection, while investigating how well the virus is transmitted naturally via mosquitoes.

A second WNV study, done in close partnership with the USGS Fort Collins Science Center , investigates the effects of the disease on kestrels, a raptor prominent along the Front Range of Colorado. While nationwide monitoring of crows and blue jays continues, raptors and other passerine species have yet to be adequately studied. Scientists are monitoring the kestrels by taking tissue samples from adults, nestling, and fledgling birds over the course of between 12 and 30 months. The results of this study will help scientists understand the effects WNV is having on kestrel populations.

The third study looks at five non-native and one native Hawaiian bird species to determine their susceptibility to the virus, as well as testing the natural transmissibility of the virus. Of particular interest is the native golden plover, which occasionally migrates to Hawaii from the continental U.S, and could potentially spread WNV to the islands. We will also study the Japanese white-eye because it shares habitat with many native Hawaiian forest birds as well as Java sparrows, Laceneck and Zebra doves, and Mynah birds. This study will help scientists further understand the impacts of WNV if it reaches Hawaii.

Other studies are planned to determine the susceptibility of indicator reptile, amphibian, and mammalian species to WNV, and to monitor the changing genetic structure and virulence of the disease.

These studies, together with the collaborative programs and monitoring USGS is conducting with the CDC and other local public health and vector control agencies, paint a picture of a comprehensive research strategy to better understand WNV in wildlife and ecosystems.