[BCNnet] West Nile Virus and gamebirds

[Judy Pollock]

Here are some WNV facts from Ducks Unlimited with an interesting
speculation that the virus may not affect wild waterfowl.  Some of the
cautions that they advise - about protecting yourself in the field and when
handling birds - also apply to some of us.  

What Hunters Need to Know about the West Nile Virus

Memphis, September 23,
2002 - With waterfowl hunting season just around the 
corner, hunters want
to know about the risk of contracting West Nile (WN) 
virus from either
handling or consuming wild game birds. All currently 
available information
indicates that West Nile virus is primarily spread 
through mosquitoes.
There are no reported cases of West Nile virus being 
contracted through
the handling or consumption of wild birds, however West 
Nile virus is new
in North America and there is still much to be learned 
about the
disease.

Over one hundred species of birds have been found to carry the
virus, with 
members of the Corvidae family (crows, blue jays, ravens)
showing the 
greatest mortality from the virus. To date, specimens of the
following game 
birds have been reported positive for WN virus: sandhill
cranes, mourning 
doves, mallards, wood ducks, Canada geese, ruffed grouse,
wild turkeys, and 
ring-necked pheasants. However, based on studies
conducted since the virus 
first appeared in North America, scientists
believe wild waterfowl may be 
immune to the WN virus. While mallards, wood
ducks, and Canada geese have 
tested positive for the virus, the infected
birds were all domestic 
waterfowl living on park ponds, zoos, and in urban
settings. Furthermore, 
thousands of birds die each year from avian
botulism, many of which are 
randomly tested for botulism and WN virus. To
date, none of these wild 
waterfowl have tested positive for WN virus.

How
It's Spread

When a mosquito bites a bird infected with the virus, the
mosquito becomes 
infected and can transmit the virus to humans, horses,
dogs, or other birds 
that it bites thereafter. Of the forty species of
mosquitoes that transmit 
the virus, three species Culex pipiens, C.
Restauns, and C. salinarious 
have been implicated as the most common
vectors. Larvae of these species 
are most commonly found in urban
settings, where mosquitoes lay eggs in the 
stagnant water of bird-baths,
tin cans, old tires, plastic bottles, rain 
gutters, etc. These
"container-breeding" mosquitoes are rarely found in 
healthy wetlands such
as the ones used by North America's waterfowl. In 
healthy wetlands, versus
partially drained and impacted wetlands, predators 
and water movement will
generally reduce mosquito populations.

Be Prudent, but not
Paranoid

Despite increased media attention, there is no cause for panic
about West 
Nile Virus but neither is there room for denial. Hunters should
follow the 
usual precautions when handling wild animals, and if you expect
to 
encounter mosquitoes in the field, wear long pants, long-sleeves, and

mosquito repellant. Here are a few more recommended precautions that
should 
minimize any possible risk:

- Do not harvest or handle sick game
birds.

- When cleaning game or handling live or dead birds, use gloves in
order to 
- prevent blood-to-blood contact

- Cook game birds until well
done

- Soak any utensils used to prepare game birds in a solution of one
part 
household bleach and 10 parts water for 20 minutes.

- Most
importantly, hunters should avoid mosquitoes as they are the most 
likely
means of acquiring West Nile virus. Hunters participating in early 
teal
season hunts should apply insect repellant to clothing and skin.

- At
home, look for stagnant water in bird-baths, plant trays, old tires,

wheelbarrows, and other containers around your yard. If you find standing

water, pour it out, and be diligent about re-checking these areas at least

once a week.

Dogs and West Nile Virus

Cases of WNV have been reported in
dogs in the U.S., but most infections 
did not cause severe illness in
infected dogs. However, veterinarians in 
Illinois recently confirmed the
first documented canine death from West 
Nile Virus in North America. An
8-year-old Irish setter/Golden Retriever 
mix, a wolf and three gray
squirrels in Illinois died of West Nile 
infection. Officials do not expect
an epidemic of the virus in household 
pets, but caution that older dogs,
puppies, and dogs that already have weak 
immune systems could be at risk.
The infected dog in Illinois showed 
neurological symptoms, including
unusual head bobbing, lethargy, and 
progressive weakening. The virus
appears to have been transmitted by 
mosquitoes, and researchers stress
that people and other pets have a low 
risk of contracting the virus from
an infected dog. Dog owners should 
minimize their pet's exposure to
mosquitoes by using screened kennels, 
and/or repellents approved for use
on animals. Do NOT use DEET on dogs. 
Owners should also limit early
morning and late afternoon walks or training 
sessions, as this time of day
leaves people and animals most susceptible to 
mosquito bites.

Should your
pet contract the virus, don't panic. Officials say there is no 
reason to
destroy an animal because it has been infected with WNV.

Full recovery is
likely, and direct transmission of the virus to you or 
other animal is
unlikely. Researchers are currently developing WNV vaccines 
for domestic
animals.

What is West Nile Virus?

West Nile virus belongs to a group of
disease-causing viruses known as 
flaviviruses, which are spread by
insects, usually mosquitoes. The virus 
was first isolated in Uganda in
1937, and is most commonly found in Africa, 
West Asia, Europe, and the
Middle East. It first reported in the United 
States in New York State in
the summer of 1999. WN Virus is closely related 
to St. Louis encephalitis,
a naturally occurring virus in the U.S. and 
Canada. As of September 18,
2002, WN virus has been detected in 42 States 
and the District of
Columbia. The geographic range of WN within the U.S. 
has grown each year.

Judy Pollock
Evanston (Cook)
bobolnk@ix.netcom.com