Office of the Regional Executive for Biology - Central Region
 |
| About USGS / Science Topics / Maps, Products & Publications / Partnerships / Education / Newsroom / Jobs |
September 16, 2002
Here is a short blurb that summarizes the extent of WNV infection in birds. CDC's list is now above the 111 species quoted in the article. We all tend to think "corvids" when thinking of WNV, but as Kathy points out in the report, there aren't any bird species we know that are resistant to the virus.
The total equine WNV cases reported by USDA as of Sept 8 is 3453. As I mentioned in another update, this number is generally considerably lower than the number obtained if you add all the reports from various sources in each of the states. In Manitoba, the number of equine cases is rising dramatically, now over 100 known reports. Cases continue to climb. The California-origin human case of WNV has been confirmed. She had not recently traveled out of the state, so the presumption is the disease was contracted locally. Nothing has shown up on surveillance in wildlife or horses. There are 2 other human cases in CA, but both known to have been contracted outside the state. Similarly, a case in Arizona (human) appears to have been derived from Ohio. CDC now lists 1438 human cases with 64 deaths.
To get away from WNV for a change, the European Commission representing the European Union on FMD, set the stage for vaccination as the first, emergency, response to FMD outbreaks (see report below). This is a significant revision of the EU policy against vaccination which has been in place since 1991. As most of you on this list are aware, the British situation with massive slaughter and millions of pounds in expense has been widely criticized for their response. Similar "contact slaughter" policy is still the accepted response to FMD in this country, though perhaps that could be reexamined in light of the worldwide distribution of FMD and the European acceptance of vaccination as a first line defense.
Thomas J. Roffe, PhD, DVM
Northern Rocky Mountain Science Center
USGS-BRD
FWP Bldg, 1400 S. 19th Ave.
Bozeman, MT
T: 406-994-5789
F: 406-994-4090
Cell: 406-539-4955
Supporting Documents:
Date: Mon 9 Sep 2002
From: Pablo Nart <p.nart@virgin.net>
Source The Globe and Mail, Mon 9 Sep 2002 [edited]
<http://www.globeandmail.ca/servlet/ArticleNews/front/RTGAM/20020909/wwestnile0909/Front/homeBN/breakingnews>
Effect of West Nile Virus on Bird Populations
West Nile virus, first spotted in the U.S. in a sick crow 3 years ago, has now attacked at least 111 species of birds, including the Bald Eagle and the endangered Mississippi Sandhill Crane. The spread of the virus has surprised and alarmed wildlife researchers because it has happened so quickly. Last year, West Nile virus had been detected only in about a dozen species of birds.
This year, hundreds of birds of prey, particularly Red-tailed Hawks and Great Horned Owls, have been found dead in the upper Midwest, said Kathryn Converse, a wildlife disease specialist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wis. About 400 owls and hawks died in Ohio alone in what one wildlife official called "a major die-off."
The carcasses were being tested for West Nile virus, which has been confirmed in several cases. West Nile virus also has killed such birds in the wild as the Ruby-throated Hummingbird and Canada Goose, and exotic and captive species such as the Macaw and the Chilean Flamingo, according to the Centers for Disease Control and Prevention (CDC) Web site. Of particular concern are the deaths of any endangered species, like the Mississippi Sandhill crane, which numbers only about 120. It is one of 6 types of Sandhill Crane. Since 1999, the virus has also killed at least one Bald Eagle, a threatened species, according to the CDC Web site. "We don't know of any birds that can't be affected by the virus," Ms. Converse said. It's impossible to know exactly how many birds have died from the West Nile virus, wildlife officials say, because the only way to confirm the virus in birds is to test them after they die. Also, federal agencies like the CDC and Geological Survey rely on state and county health officers to report the bird deaths. But those officials are mainly interested in birds only as a tip-off that mosquitoes carrying the virus have shown up in their areas, so that people can be warned. News that the virus is spreading in bird populations is frustrating for bird caretakers like James Mejeur, curator at the National Aviary in Pittsburgh, because the illness is hard to detect, treat, and prevent. Although veterinarians are experimenting with a vaccine approved for horses, the most effective way to prevent birds from getting sick is to control the mosquito population, Mr. Mejeur said. Some institutions with captive bird populations install mosquito netting."It's manageable for us because the majority of our bird population is inside," said Mr. Mejeur, whose facility has lost three magpies and a crow this year. "But it is a tough time for zoos and other places that can't control the mosquitoes and have large populations of birds." The horse vaccine has not been widely tested on birds, but the few facilities that have tested it found the birds were not harmed by it, Mr. Mejeur said. Still, birds must be injected 3 times over a span of 3 months, which can be traumatic to wild populations, he said.
At the Raptor Center at the University of Minnesota, caretakers suspect the raptors may have the virus when they develop tremors, a blank stare, and confusion. But other illnesses can cause similar symptoms, said Pat Redig, the center's director. At that point there's not much veterinarians can do but give the animals fluids, antibiotics, and special feedings that may help their immune systems. But many raptors infected by the virus die after symptoms appear, said Mr. Redig. The Raptor Center has been studying and caring for eagle, hawk, owl, and falcon populations since 1974.
[A similar news report from the Beaver County Times, submitted by Lawrence Hribar <LarryHribar@aol.com> of Marathon, Florida contained the additional statement that the CDC's list of affected [avian] species is already higher than 110 -- including species such as the Snowy Owl and the Golden Eagle -- and grows every day.]
Date: Fri, 13 Sep 2002
From: ProMED-mail <promed@promedmail.org>
Source: The Telegraph, Fri 13 Sep 2002 [edited]
Brussels to control the foot and mouth fightBrussels would take charge of future foot and mouth epidemics under a new European directive. The European Commission has concluded that no single member state can be trusted to tackle epidemic diseases threatening the whole union. The EC would have power to order vaccination. Countries worried by an outbreak in another EU state could trigger mandatory vaccination, meaning that Ireland or France could effectively override Britain's slaughter policy. The intervention by Brussels ends the reliance on mass slaughter that saw 6 million animals burned in Britain last year. The cull turned much of the countryside into a no-go area, led to a public outcry across Europe, and was denounced as "immoral" by the Dutch farm minister.
The draft law moves the European Union towards a policy of emergency vaccination. The commission will be able to order vaccination if infected livestock are not culled within 24 hours and contiguous animals within 48 hours. In Britain it took as long as 7 days to carry out culls in the early phase, before the Army was brought in. The directive is to be published in early October 2002. The draft version obtained by The Telegraph says: "The decision to introduce vaccination shall be taken by the commission on request of the member states directly affected, or on request of the member states under risk, or on the commission's own initiative."
Brussels is to stockpile a million doses of the vaccine for immediate use and a further 4 million to be ready within 10 days. The commission will police member states to ensure that their contingency plans are up to scratch. Specific requirements are set down for the number of vets and surveillance personnel and biannual field drills along the lines of recent exercises in Australia.
The new directive is a response to a year-long inquiry by the European Parliament, which has highlighted major shortcomings in British policy. The shift away from the slaughter policy has been made easier by new international rules agreed in May, which make it less costly for countries to resort to ring vaccination. These rules limit the loss of foot and mouth free status from 12 to 6 months and confine the affected area to regions rather than whole states.
U.S. Department of the Interior | U.S. Geological Survey
URL: http://biology.usgs.gov/cro/WNV9-16-02.htm
Page Contact Information:
tlwilliams@usgs.gov
Page Last Modified:
