West Nile Virus

[LadyHawke]

i found this article
Equus June 2003 issue

INFECTION
A Most Unusual Host

Last September, nearly 200 alligators died suddenly at a farm near Orlando, Florida after exhibiting signs of neurological impairment. The nxt month, the farm's owner sent several other ill alligators to the University of Florida's College of Veterinary Medicine for evaluation. Subsequent testing of three of the alligators confirmed that they were infected with West Nile Virus (WNV).

These are the first reported cases of WNV in alligators, according to Elliot Jacobson, DVM, professor of zoological medicine at the university and a specialist in reptile infectious diseases. "I've been in contact with people in South Africa, and there is no evidence of the virus in Nile crocodiles that are being farmed there," he says.

Of the three alligators examined, says Jacobson, two were fairly listless but one exhibited neurological signs. After the reptiles were euthanatized, necropsies were performed, and pathologists found evidence of meningitis and encephalitis as well as inflammation of the heart and liver.

More disturbing were the high levels of WNV found in the reptiles' blood: "The viral loads approached those found in birds, which means that alligators may represent another amplification host," says Jacobson. "Potentially, they could be able to transmit WNV to other hosts, just as birds do."

Previously, other farms with captive alligators in Florida and Georgia had reported similar die-offs associated with similar clinical signs, but there's been little research into alligator diseases. "Its one thing to show clinical signs, its another to have the pathology to support it," says Jacobson. "We've heard of other farms infected, but the people did not submit the animals. Fortunately, there was one guy (in Florida) who pursued it."

It is not known how alligators are infected, but Jacobson says that "its more then likely" that the route was mosquito bites. Studies are currently under way to determine whether certain mosquitos regularily fed on alligators. In addition, further studies in Florida will look at 400 alligators from across the state to see if there's evidence of exposure among wild alligators. Researchers hope to know more once the state study has been completed this fall.

[KrokadilyanGuy3]

There's alot of viable reasons I see why this isnt such a shock. Such as the constant warm temperatures farm stock animal are kept in, the stagnant waters, ect. I however think that themain and most probable reason why Crocodilians are capable of inhabiting this virus is because of the very close relationship they have with birds. Crocodilians are far more closely related to birds than any herp. So that is a very good factor, that I would believe to be the most probable cause.