In article , "NewsUser"
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"paghat" wrote in message
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Though there is no possibility of dead birds per se infecting anyone with
WNV, parasites on the bird just might be able to transfer the disease. It
is believed the disease reaching certain hawk populations because of a
tendency to scavenge dead birds & having infected bloodsucking parasites
transfer to a new host. Humans get it from mosquitos & mosquitos can
transfer it from any number of mammals or birds to humans. So though I
don't think it has been studied, it's at least a credible hypothesis that
contact with infected parasites could provide a mild threat to humans.
There are several other zoonotic diseases for which parasites are
intermediate carriers.


Please provide the source of the info about parasites (other than mosquitos)
transmitting WNV in hawk populations.

At the moment while east coast crows & jays seem mainly to get it from
mosquitos, it is beginning to appear that raptors around the Great Lakes
get it from various species of hippoboscids or louseflies. Do a medline
search for West Nile & Hippoboscids & you will find a great deal already
published, but most of the studies on this began late 2002 after the great
raptor die-off around the Great Lakes states & Canada, & are only reported
in birdwatcher newsletters & by falconer clubs, the full studies
themselves still pending publication.

Research is being done by Kay McKeever in Ontario, Marianne Socha in Ohio,
& several others, but McKeever's research is the most widely reported.
You'll find a little about this he
http://www.calhawkingclub.org/chccom...nv_default.htm

There's much else available in print newsletters about kestrals, great
horned owls, bald eagles, merlins, & golden eagles felled by WNV carried
to them by louseflies, which infest primarily the largest birds. Other
parasitic flies may eventually be found to be involved in specific
regions, this is as yet an unknown factor that lends everyone involved
(citizens gathering bird carcasses, lab technicians analyzing blood, &
everyone in between) to take precautions under the assumption that the
worst is possible, though some of the worst possibilities will likely be
disproven (like the possibility of bloodsuckers other than fly species
carrying the virus even transiently). Parasites outside the fly groups are
not apt to be found to be capable of carrying WNV long term, but it's not
out of the question that other sorts of external parasites could be able
to carry it NOT in saliva as do the louseflies & mosquotos, but in
partially injested blood for very short periods, infectivity yet to be
proven or disproven. Even if the only additional parasite guaranteed to be
a problem turned out to be the lousefly, though, it harbors amidst quills
so is VERY apt still to be present on carcasses awaiting its chance to
move to a living host, in many cases to a scavenging hawk.

Bare in mind this problem was ignored for a very long time; good studies
began to appear from a very few regions in 1999 (for New York especially,
where the earliest mass-die-offs occurred among crows, followed in 2002 by
mass die-offs in Brookland, DC). Only with publication of a batch of
Cornell findings last year, the sudden die-off of raptors in Ohio &
Michigan also in 2002, & the number of wire service articles that climbed
on the bandwagon in the wake of a very few human deaths, were monies at
long last filtered toward the avian WNF problem.

One more factor as yet neither proven nor disproven is the possibility of
bird mites transmitting WNV. They do transmit equine encephalitis to
birds, a disease very similar to WNV, & there is speculation that they may
also be able to transmit WNV. But to date there is no evidence to prove or
disprove this possibility.

A tragic discovery at the Cascade Raptor Center in treating injured
raptors for release showed definitively that WNV can be carried to raptors
(& to mammalian predators as well) directly from eating the carcasses of
infected prey (bird or mammal). This was previously not thought to be
possible, but now the word has gone out never to feed preditors
wild-caught rodents or roadkilled squirrels nor even fresh-killed chickens
from unaproved sources.

Many of the studies are so far only three or four months in progress, &
much will be finding its way into scientific publication in the next 18
months or so. In the meantime birdwatcher newsletters & occasional leaks
to wire services provide hints of what is being proven or disproven here &
there. A whole raft of new studies are now set up to monitor Atlantic &
Gulf coast states during mosquito system, but few of these studies predate
2001 & many are having their inauguration in forthcoming mosquito season
summer-autumn 2003. This is something we can all watch unfolding for worse
or for much worse. The final outcome for many bird species but especially
for crows, jays, & raptors is yet to be seen. It doesn't look good so far,
but barring discovery of vaccines that can be delivered to the wild by
oral means (so far vaccines only work with capture & innoculation), then
the best hope is that after the massive die-offs are finished, very few
species will be lost altogether, & survivors will be impervious to the
virus & rebuild populations with unaffected offspring.

I believe there are 36 species of
mosquito in the US known to carry WNV but have not yet seen mention of
other parasites.

You were probably reading about transmission to people, which to date
SEEMS to be only possible through the intermediate carrier of a mosquito.
The situation with birds is a little different, & even the present data
about transmission to humans could well be ammended with time & better
studies -- time will tell.

-paghat

Thanks.

karen

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
See the Garden of Paghat the Ratgirl: http://www.paghat.com/

Good information. I will do some searching on the Hippoboscids in
particular. The article you linked to mentions WNV being found in ticks in
Africa and Asia (with uncertainty of their role in transmission), but it
makes sense any blood-sucking insect could pick it up.
Thanks again.

karen

"paghat" wrote in message
news
In article , "NewsUser"
wrote:

"paghat" wrote in message
news
Though there is no possibility of dead birds per se infecting anyone
with
WNV, parasites on the bird just might be able to transfer the disease.
It
is believed the disease reaching certain hawk populations because of a
tendency to scavenge dead birds & having infected bloodsucking
parasites
transfer to a new host. Humans get it from mosquitos & mosquitos can
transfer it from any number of mammals or birds to humans. So though I
don't think it has been studied, it's at least a credible hypothesis
that
contact with infected parasites could provide a mild threat to humans.
There are several other zoonotic diseases for which parasites are
intermediate carriers.


Please provide the source of the info about parasites (other than
mosquitos)
transmitting WNV in hawk populations.

At the moment while east coast crows & jays seem mainly to get it from
mosquitos, it is beginning to appear that raptors around the Great Lakes
get it from various species of hippoboscids or louseflies. Do a medline
search for West Nile & Hippoboscids & you will find a great deal already
published, but most of the studies on this began late 2002 after the great
raptor die-off around the Great Lakes states & Canada, & are only reported
in birdwatcher newsletters & by falconer clubs, the full studies
themselves still pending publication.

Research is being done by Kay McKeever in Ontario, Marianne Socha in Ohio,
& several others, but McKeever's research is the most widely reported.
You'll find a little about this he
http://www.calhawkingclub.org/chccom...nv_default.htm