Information on West Nile provided by Dr. Lisa Reed, Rutgers University:
5 Dec 1999
I thought I'd let you know that we've been sampling wild birds, including crows, here in New Jersey for West Nile Fever virus and next week I'll be presenting some preliminary results at the Northeastern Mosquito Control Association meeting in Massachusetts. We sent 315 samples to Nick Komar at the CDC, and he was able to analyze 260 before this upcoming meeting. The samples included both local and migratory species (with 128 American and Fish Crows). We had two birds (one American one Fish Crow) with high antibody titer levels, plus six other crows (no other species, as of yet) with low antibody titers. Of the six, four were tentatively classified as WN (vs SLE) and the other two as "Unidentified flavivirus." This last bit is interesting since previous Old World outbreaks suggest that highest titer levels are associated with the end of outbreaks, possibly suggesting that these low-titered birds were infected earlier (like last year?). I'm not sure how long it takes before antibody reduction occurs and we did sample toward the end of October, so this might also represent a decrease from an infection acquired this year. Might crows here mimic Corvus corone cornix as a major player in WN vector ecology?
Just thought you'd be interested,
Lisa Reed, Dept Entomology, Rutgers
9 Dec 1999
Please feel free to put up a summary statement - I'm planning on putting up a page later on, but I don't know when I'll get a chance to do so. Once I do, I'll send you the URL (but this won't be until after the holidays, I'm certain).
Anyway, here is the list of species we caught (over 300 samples sent in, about 260 analyzed to date)
Peacock (not your typical NJ species - was sampled along with the chickens at an animal shelter)
Black-throated Blue Warbler
Eastern Tufted Titmouse
The crows, House Sparrow, Gray Catbird, and Yellow-rumped Warbler were most commonly caught (> 15 individuals). No other species than Corvus were found to have been exposed to WN virus. Our calculations for the infection rates are about 5% for American Crow and a bit over 4% for Fish Crow.
We trapped at 4 urban sites (central and northern NJ) and two non-urban (Cape May - migratory). The southern sites have historical netting records in tracking EEE. We will be setting up a surveillance program for WN, including sentinel chickens and monitoring urban birds. In addition, we have a grad student who will be monitoring the non-urban birds for her thesis work.
Lisa Reed, Dept. Entomology, Rutgers University, NJ USA