Date: Sun, 2 Nov 2003 21:08:12 -0500 Reply-To: Maryland Birds & Birding Sender: Maryland Birds & Birding From: David Mozurkewich Subject: Re: Where are the Titmice? Dead of West Nile Virus? In-Reply-To: <19d.1c7768b8.2cd6d94b@aol.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII On Sun, 2 Nov 2003, Carol Schreter wrote: >... > So, why are there no titmice in some areas? Could very well be West >Nile virus. Or maybe not. It could be the distribution of natural food sources. >... > I got one carcass to the Dept. of Agriculture's Animal Lab in >Frederick, Md, to Dr. Virginia Pierce. She did a necropsy and then >sent a tissue sample to Texas for West Nile Virus testing. Diagnosis: >This bird died of a combination of West Nile Virus (WNV) and fungal >pneumonia (transmitted by air-borne spores). Bird was probably >weakened by the pneumonia first, then died of West Nile virus -- >without showing any of the characteristic signs of WNV, such as >enlarged heart or enlarged brain. I don't know what test was used to determine this bird died from WNV, but most tests for viral diseases involve testing for the antibodies. If so, a positive test-result means the bird had the disease sometime in the past. It does not mean the bird had an active and fatal case of the disease when it died. For a new, rare, or always fatal disease, an antibody test is sufficient. But for a common, mild disease it tells us almost nothing. Everyone who dies in automobile accidents will test positive for common cold antibodies, but you cannot then claim they died from the common cold. Since the bird did not show any of the "secondary" indicators of the disease (listed at the end of the previous paragraph), I am unwilling to accept the diagnosis without more information. Does anyone besides me remember the first year of this epidemic? Of all the dead birds turned in for testing that year, MORE THAN HALF died of pesticide poisoning and had no evidence of having encountered WNV. Now that WNV is so widespread, all deaths seem to be attributed to the disease -- just like they were before the initial testing that revealed the pesticide poisoning. This is too convenient; pesticide deaths are no longer being reported but I have seen no evidence that our practices involving those chemicals have improved. Before the flames hit, I am NOT saying that the dangers of West Vile Nirus are a hoax; I AM CAUTIONING against attributing ALL evils to the current bad guy. Dave David Mozurkewich Seabrook, PG MD USA mozurk at bellAtlantic.net ======================================================================= To leave the MDOsprey list, send e-mail to listserv@home.ease.lsoft.com with the following message in line 1: signoff mdosprey ======================================================================= =========================================================================