Extracts from a study of West Nile Virus, recorded on the CDC website:
Evidently they had been exposed to the virus but it had either not affected the brain or had insufficient effect to interfere with their activities. Whether it affected the kidneys in these cases, or their systems were successful in warding off the virus almost completely is anyone's guess.
When I take in a bird from my balcony who has PMV, I half expect to find more. Although I found three in ten days in the summer of 2008, it's usually just one case in several months. I've often wondered about that, but maybe what came out of that study is one possible explanation. That I don't see it doesn't mean it isn't there.
http://www.cdc.gov/NCIDOD/eid/vol10no12/04-0511.htm
John
At first, I found that surprising since pigeons badly impaired from PMV would be unlikely to survive long unaided, but then I recalled a couple of references to the effect that pigeons which demonstrate the neurological symptoms are just the tip of the 'PMV iceberg'. Many more do not, and the only signs may be watery droppings and excessive thirst, from the effect on the kidneys.
Evidently they had been exposed to the virus but it had either not affected the brain or had insufficient effect to interfere with their activities. Whether it affected the kidneys in these cases, or their systems were successful in warding off the virus almost completely is anyone's guess.
When I take in a bird from my balcony who has PMV, I half expect to find more. Although I found three in ten days in the summer of 2008, it's usually just one case in several months. I've often wondered about that, but maybe what came out of that study is one possible explanation. That I don't see it doesn't mean it isn't there.
http://www.cdc.gov/NCIDOD/eid/vol10no12/04-0511.htm
John