Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bird diversity lessens human exposure to West Nile Virus

08.10.2008
A study by biologists at Washington University in St. Louis shows that the more diverse a bird population is in an area, the less chance humans have of exposure to West Nile Virus (WNV).
Now, let's hear it for the birds.

When the red, red robin comes bob, bob bobbin' along, think West Nile Virus (WNV). Robins are anthrophilic - they love being around humans - and it's relatively easy for mosquitoes to take their blood meals from them because robins feed so much on the ground, making them a very common reservoir species for transferring WNV to humans.

"The bottom line is that where there are more bird species in your backyard, you have much lower risk of contracting West Nile fever," said Brian Allan, doctoral candidate in biology in Arts & Sciences at Washington University in St. Louis. "The mechanisms are similar to those described for the ecology of Lyme disease. Most birds are poor reservoirs for West Nile Virus, and so mosquito bites taken on them are 'wasted' from the perspective of the virus. Where many bird species exist, very few mosquitoes get infected, and so we humans are at low risk. A few bird species are highly competent reservoirs, and these tend to occur in urbanized and suburbanized areas where bird diversity suffers."

The most common "reservoir" species that urbanites and suburbanites and even rural dwellers in heavily farmed landscapes see are crows, grackles, house finches, blue jays, sparrows and American robins, with the robin being the most prolific carrier of WNV. Robins are anthrophilic — they love being around humans — and it's relatively easy for mosquitoes to take their blood meals from them because robins feed so much on the ground.

Allan, his advisor Jonathan M. Chase, Ph.D., associate professor of biology, and 14 collaborators from numerous institutions will publish their findings in a forthcoming issue of Oecologia.

While diversity of bird species is important in this scenario, that factor alone doesn't tell the whole story.

"It's not just about the number, but their relative proportions," Allan said. "It's a combination of richness - the number of species — and evenness — their relative proportions. In urban and suburban areas you see lower species richness and lower community evenness. For instance, you might have five species present, but in 100 animals 90 are just one species. That's why species number is only half the equation."

Allan and numerous graduate students began the research five years ago as they just entered graduate school and the topic of West Nile Virus was just beginning to receive lots of attention and the ecology of the organism hadn't been studied much. They identified a variety of field sites, both urban and rural, with their base of operations at Washington University's Tyson Research Center, a facility 22 miles west of St. Louis comprised of 2,000 acres of woods, glades and prairie.

They performed bird surveys at the sites, put up a variety of mosquito traps and studied different mosquito species and their ability to transmit the virus. Using kits provided by the Center for Disease Control, they tested the mosquitoes and found three positive pools.

"The infection rates are actually remarkably low, with maybe one in 1,000 carrying WNV," Allan said.

They expanded their study to include mosquito infection data from the St. Louis City and St. Louis County Health departments. They saw the same patterns. The greater bird diversity, the lesser incidence of WNV; the lesser diversity, the greater likelihood of WNV.

To broaden their finding even more, Allan and his colleagues used national data sets on human cases of WNV and a tool called the Shannon Diversity Index to estimate the diversity of bird populations across the U.S. These data are conducted nationwide by amateur bird watchers for the United States Geological Survey's Breeding Bird Surveys.

"We're seeing locally and nationally that bird diversity is a buffer against the occurrence of West Nile Virus in humans," Allan said. "That's a win-win situation for both conservation and public health."

Brian Allan | EurekAlert!
Further information:
http://www.wustl.edu

Further reports about: Bird diversity Lyme disease WNV West Nile virus bird population bird species

More articles from Studies and Analyses:

nachricht Real-time feedback helps save energy and water
08.02.2017 | Otto-Friedrich-Universität Bamberg

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Positrons as a new tool for lithium ion battery research: Holes in the electrode

22.02.2017 | Power and Electrical Engineering

New insights into the information processing of motor neurons

22.02.2017 | Life Sciences

Healthy Hiking in Smart Socks

22.02.2017 | Innovative Products

VideoLinks
B2B-VideoLinks
More VideoLinks >>>