Published Date: 2009-08-08 20:00:06
Subject: PRO/AH/EDR> Botulism, avian - USA: (NV)
Archive Number: 20090808.2814
BOTULISM, AVIAN - USA: (NEVADA)
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: 31 Jul 2009
Source: RGI.com [edited]
Botulism suspected in Reno duck deaths
Jasmine McCarty of Sun Valley got quite a shock Friday [31 Jul 2009]
morning during a visit to Teglia's Paradise Park in northeast Reno,
Nevada. She said she and 3 of her grandchildren, ages 4, 6 and 7,
found about a dozen ducks lying dead near the edge of the park's large pond.
"It was freaky," McCarty said. "Poor little ducks. It upset
6-year-old grandson Christopher so bad, he threw up."
Concerned and unsure what caused the ducks' demise, McCarty called
911 to report the dead fowl. Washoe County Regional Animal Services
interim field supervisor Bobby Smith said he dispatched a sergeant to
Paradise Park to clean up the area.
"Apparently it looks like botulism," Smith said. "NDOW (Nevada
Department of Wildlife) and their vet were notified, the U.S.
Department of Fish and Game were notified," he said. "It's their
jurisdiction, they do the testing and all that, and I'm just waiting
to hear as to what exactly has happened."
Nevada Department of Wildlife spokesman Chris Healy said scenes like
the one McCarty and her grandchildren found Friday morning are not
uncommon during the summer when water gets warm and stagnant.
"This time of year, avian botulism happens," Healy said. Avian
botulism, which does not infect humans, is a paralytic disease caused
by the ingestion of a toxin produced by a bacteria, according to the
National Wildlife Health Center.
"This has been going on around here for a long time," said Healy,
who's been with the department 24 years. "A duck eats some kind of
dead organism and dies. Then its carcass infects the other ducks.
This is a fairly common thing."
Although the duck carcasses picked up at Paradise Park Friday still
need to be tested to confirm avian botulism, Healy said recent high
temperatures had him expecting the kind of outbreak McCarty witnessed.
[Byline: Martina Beatty
ProMED-mail Rapporteur Brent Barrett
[The sporulating anaerobic gram-positive bacillus _C. botulinum_
elaborates 7 types of antigenically distinct neurotoxins, 4 of which
affect humans: type A, B, E, or rarely type F toxin. Types A and B
toxins are highly poisonous proteins resistant to digestion by GI
(gastrointestinal) enzymes. Approximately 50 percent of foodborne
outbreaks in the USA are caused by type A toxin, followed by types B and E.
Type C botulism occurs principally in waterfowl and other birds
living in an aquatic environment and causes tremendous losses, most
notably in waterfowl in the western US. In addition to North America,
it has been reported in birds in Europe, South Africa, Uruguay, and
Australia. In the Great Lakes region, it was 1st identified in 1936
in ducks on Green Bay of Lake Michigan and in 1941 in Monroe County
marshes along Lake Erie. Type C is most often associated with
limberneck paralysis in birds.
Type E botulism is connected with consumption of fish and occurs
mainly in gulls and loons, and to a lesser extent in mergansers, mute
swans, grebes, and shorebirds. It now appears any birds or mammals
susceptible to botulinum toxin run a risk of becoming poisoned if
they scavenge dead fish. Evidence for this includes the
identification of type E toxin in a bald eagle, wood ducks, and
muskrats with fish remaining in their digestive tracts.
Typically a bird dies of some cause and the carcass is an incubator
for the anaerobes. The maggots move into the decomposing carcass,
accumulating the toxin. Other birds come to eat the maggots on the
carcass and infect themselves, dying from the very disease they
consumed, and so the circle gets larger and requires that carcasses
be picked up or the cycle continues. - Mod.TG]
[A map showing the location of the state of Nevada is at:
<http://www.infoplease.com/atlas/state/nevada.html> - CopyEd.EJP]