 |
|
Researchers investigate new suspect in West Nile deaths of pelicans
October 01, 2007BOZEMAN -- Stable flies are the latest suspect that may be involved in the West Nile virus deaths of hundreds of pelican chicks at the Medicine Lake National Wildlife Refuge in northeast Montana. West Nile virus killed 800 to 1,000 pelican chicks in 2003, averaged 400 in each of the next three summers and more than 600 this year.
Veterinary entomologist Greg Johnson of Montana State University said earlier this year that he considered the possibility that lice were transmitting West Nile virus to pelicans. He became suspicious after collecting very few mosquitoes in 2006, but seeing pelicans continue to die at a high rate. Johnson discovered previously that the Culex tarsalis mosquito is the primary carrier of West Nile virus in Montana and that the Medicine Lake refuge was one of the hot spots for the virus.
Many of the dead pelicans at Medicine Lake had lice crawling inside and outside of their beak, Johnson continued. Mike Rabenberg, deputy refuge manager, said external parasites -- especially pouch lice and feather lice -- are common on the Medicine Lake pelicans. The lice may be more prevalent, he said, on pelicans that are sick or weakened.
The lice were cleared, however, after Johnson sent pelican tissue samples and lice to the Centers for Disease Control and Prevention in Fort Collins, Colo. The lab tested approximately 800 lice, but none was found to have West Nile even though most came from pelicans that tested positive.
Stable flies caught Johnson's attention when he came across a bird with blood on its neck and some flies feeding on the blood during the third week of July. Stable flies look like common house flies, but they have a painful bite. They come from a different family than horse flies or deer flies, however.
"This (the stable fly scene) was very unusual because stable flies are only reported to feed on domestic livestock, humans and companion animals," Johnson said. "There are no reports in the literature of stable flies feeding on domestic or wild birds."
Johnson observed the stable flies feeding on birds several more times. He also collected about 1,300 flies and divided them into 60 groups. Eighteen of those groups tested positive for West Nile virus.
"This is the first report of stable flies feeding on wild birds, or pelicans for that matter, and the first report of stable flies infected with West Nile virus," Johnson said. "These results suggest that stable flies might be involved in amplification and/or transmission of West Nile virus at the pelican colony and possibly could serve as a vector of West Nile virus to other pelicans."
If the theory proves correct, he will have to modify some of his study methods because they currently focus on mosquitoes, Johnson said. He added that the number of captured mosquitoes was high this summer, as well as the West Nile infection rate in those mosquitoes.
As far as the relationship among lice, pelicans and West Nile virus goes, Johnson said the lice created wounds that could be a point of entry for the virus, however they don‛t pass along the virus.
"I don't think they are playing a primary role in West Nile transmission because they don't have to have blood for egg development, energy and survival," Johnson said. "Rather, they feed on epidermal or skin cells which creates wounds, causing blood to exude and then they feed on the blood. The wounds they cause may provide entry sites for West Nile virus, and the young pelicans can get infected that way."
The Medicine Lake National Wildlife Refuge between Plentywood and Culbertson contains the fifth largest colony of American white pelicans in North America. Rabenberg said the colony normally includes 8,000 to 10,000 breeding adults and approximately 4,000 nests. The adult pelicans fly up to 150 miles one way a day looking for food. The Medicine Lake adults fly to other mosquito-rich areas like Terry, the Fort Peck Reservoir and the Yellowstone River. They fly into Saskatchewan and North Dakota. The adult pelicans typically winter along the Gulf coast, but some reach southern Mexico.
Montana State University
The lice were cleared, however, after Johnson sent pelican tissue samples and lice to the Centers for Disease Control and Prevention in Fort Collins, Colo. The lab tested approximately 800 lice, but none was found to have West Nile even though most came from pelicans that tested positive.
Stable flies caught Johnson's attention when he came across a bird with blood on its neck and some flies feeding on the blood during the third week of July. Stable flies look like common house flies, but they have a painful bite. They come from a different family than horse flies or deer flies, however.
"This (the stable fly scene) was very unusual because stable flies are only reported to feed on domestic livestock, humans and companion animals," Johnson said. "There are no reports in the literature of stable flies feeding on domestic or wild birds."
Johnson observed the stable flies feeding on birds several more times. He also collected about 1,300 flies and divided them into 60 groups. Eighteen of those groups tested positive for West Nile virus.
"This is the first report of stable flies feeding on wild birds, or pelicans for that matter, and the first report of stable flies infected with West Nile virus," Johnson said. "These results suggest that stable flies might be involved in amplification and/or transmission of West Nile virus at the pelican colony and possibly could serve as a vector of West Nile virus to other pelicans."
If the theory proves correct, he will have to modify some of his study methods because they currently focus on mosquitoes, Johnson said. He added that the number of captured mosquitoes was high this summer, as well as the West Nile infection rate in those mosquitoes.
As far as the relationship among lice, pelicans and West Nile virus goes, Johnson said the lice created wounds that could be a point of entry for the virus, however they don‛t pass along the virus.
"I don't think they are playing a primary role in West Nile transmission because they don't have to have blood for egg development, energy and survival," Johnson said. "Rather, they feed on epidermal or skin cells which creates wounds, causing blood to exude and then they feed on the blood. The wounds they cause may provide entry sites for West Nile virus, and the young pelicans can get infected that way."
The Medicine Lake National Wildlife Refuge between Plentywood and Culbertson contains the fifth largest colony of American white pelicans in North America. Rabenberg said the colony normally includes 8,000 to 10,000 breeding adults and approximately 4,000 nests. The adult pelicans fly up to 150 miles one way a day looking for food. The Medicine Lake adults fly to other mosquito-rich areas like Terry, the Fort Peck Reservoir and the Yellowstone River. They fly into Saskatchewan and North Dakota. The adult pelicans typically winter along the Gulf coast, but some reach southern Mexico.
Montana State University
West Nile Virus Current Events and West Nile Virus News RSSOn the Trail of a Vaccine for Lyme Disease: Yale Researchers Target Tick Saliva
A protein found in the saliva of ticks helps protect mice from developing Lyme disease, Yale researchers have discovered. The findings, published in the November 19 issue of Cell Host & Microbe, may spur development of a new vaccine against infection from Lyme disease, which is spread through tick bites.
UC Davis researchers identify dominant chemical that attracts mosquitoes to humans
Scientists at the University of California, Davis, have identified the dominant odor naturally produced in humans and birds that attracts the blood-feeding Culex mosquitoes, which transmit West Nile virus and other life-threatening diseases.
What are coral reef services worth? $130,000 to $1.2 million per hectare, per year: experts
Experts concluding the global DIVERSITAS biodiversity conference today in Cape Town described preliminary research revealing jaw-dropping dollar values of the "ecosystem services" of biomes like forests and coral reefs - including food, pollution treatment and climate regulation.
Immune cells predict outcome of West Nile virus infection
Infection with West Nile virus (WNV) causes no symptoms in most people. However, it can cause fever, meningitis, and/or encephalitis. What determines the outcome of infection with WNV in different people has not been determined.
Surgical masks and N95 respirators provide similar protection against influenza
A McMaster University study has found that surgical masks appear to be as good as N95 respirators in protecting health-care workers against influenza.
La Jolla Institute announces 2.0 launch of major database to aid vaccine development worldwide
Key improvements in a major infectious disease database that will aid vaccine development worldwide were unveiled today with the 2.0 launch of the National Institutes of Health-sponsored Immune Epitope Database and Analysis Resource (IEDB).
OHSU scientists partner with others to form center aimed at combating infectious diseases
Oregon Health & Science University and the University of Washington, along with a number of partner institutions across the Northwest, have received federal funding to form a regional research center aimed at combating emerging or re-emerging infectious diseases that pose a serious threat to human health.
Field stations foster serendipitous discoveries in environmental, biological sciences
North America's biological field stations have long been home to a rich legacy of research results, scientists say, making them important places for serendipitous discoveries in the biological and environmental sciences.
New wheat disease could spread faster than expected
Both plant and human diseases that can travel with the wind have the potential to spread far more rapidly than has been understood, according to a new study, in findings that pose serious concerns not only for some human diseases but also a new fungus that threatens global wheat production.
New test may help to ensure that dengue vaccines do no harm
As vaccines against a virus that infects 100 million people annually reach late-stage clinical trials this year, researchers have developed a test to better predict whether a given vaccine candidate should protect patients from the infection, or in some cases, make it more dangerous, according to an article just published in the journal Clinical and Vaccine Immunology.
More West Nile Virus Current Events and West Nile Virus News Articles
 |
West Nile Virus (Diseases and Disorders) by Melissa Abramovitz (Author) West Nile virus had never been seen in the Western Hemisphere before 1999. Now, it's everywhere in the United States. Find out more about this new health threat and what's being done about it. (20051001) |
 |
Recombitek West Nile 10 Dose (1 mL) by Recombitek Recombitek West Nile Virus Vaccine is recommended for the vaccination of healthy horses as an aid in the prevention of viremia due to West Nile Virus infection. This is Live Canarypox Vector vaccine. Reconstitute the lyophilized vaccine with accompanying liquid diluent and aseptically inject a 1ml dose by intramuscular route. For primary vaccination, revaccinate with a second 1 ml dose of this product 4 to 6 weeks later. Annual revaccination with a single dose is recommended. This contains 10 Doses: 10 x 1 Dose, Lyophilized 10 x 1 mL, Sterile Diluent Doseage: Reconstitute the lyophilized vaccine with accompanying liquid diluent and aseptically inject a 1 ml dose by intramuscular route. For primary vaccinate with a second 1 ml dose of this product 4 to 6 weeks later. Annual revaccination... |
![West Nile Virus [Explicit]](http://ecx.images-amazon.com/images/I/511096CMYZL._SL160_.jpg) |
West Nile Virus [Explicit] Brotha Lynch Hung (Primary Contributor) |
 |
ThermaCELL Mosquito Repellent Refill Set 1 set by ThermaCELL Mosquito repellent refills. |
 |
Off! Insect Repellent II, Aerosol, Fresh Scent - 15% DEET (no longer unscented), 6 oz by OFF! Provides hours of effective protection from mosquitoes, gnats and biting flies (deer flies, sand flies, stable flies and black flies). Also repels ticks, chiggers and fleas from treated skin and clothing. OFF! Insect Repellent II is not greasy, won't stain and resists perspiration. Sprays upside down too. Contains No CFCs or other ozone depleting substances. |
|
West Nile Virus by Catcher | |
 |
FaceDoctorX Anti-Mosquito Soap, 100 g (3.35 oz) by Face Doctor The new way to stop mosquitoes from biting! Non-Toxic, No side effects, Contains 100% herbal extracts! The unique formula found in this soap was developed by Dr. Archibald of the Australian National Biological Laboratory. It contains 100% herbal extraction. Once you shower with this soap, it will repel mosquitoes from touching your skin. It will also relieve insect bites and itching if you did not use the soap offhand. Active Ingredients Function: Eucalyptus oil: Repel mosquitoes, relieve tired muscles. Citronella oil: mosquito repellent. Menthol: Insect and mosquito repellent, refreshes and revitalizes skin. Lavendula: Represses bacteria, diminishes inflammation. Calendula: Diminishes inflammation, relieves itching. Made in China. |
|
Protecting Yourself and Your Community From West Nile Virus x VHS tape | |
 |
West Nile Virus (Deadly Diseases and Epidemics) by Jeffrey N. Sfakianos (Author), I. Edward Alcamo (Editor), David Heymann (Editor) Often a serious illnes, West Nile Virus seems to arise as a seasonal epidemic in North America, beginning in the summer and continuing into the fall. |
 |
Giant Microbes - West Nile (West Nile virus) - Plush by Giant Microbes The flood of press coverage isn't for the birds. WNV can send you to the after-life. |
| © 2009 BrightSurf.com |