Contact: Joanna Wilson, DNREC Public Affairs 302-739-9902.
Public asked to report sick or dead wild birds
to DNREC’s Mosquito Control Section for 2012 West Nile virus monitoring
DOVER (May 30, 2012) – The DNREC Division of Fish and Wildlife’s Mosquito Control Section is again asking the public’s help in monitoring West Nile virus by reporting sick or dead wild birds of certain species that may have contracted the virus. West Nile virus (WNV) is a mosquito-borne disease that rates of considerable concern to the health of humans and unvaccinated horses.
Beginning Monday, June 4, the Mosquito Control Section requests that the public report sick or dead birds of the following species only: crows, blue jays, cardinals, robins, and hawks or owls, plus clusters of five or more sick or dead wild birds of any species. Bird specimens should have been dead for less than 24 hours and not appear to have died or been killed by other obvious causes. The collecting and testing of virus-suspect wild birds may continue through the end of September, said Dr. William Meredith, Delaware’s Mosquito Control administrator.
After initial processing by the Delaware Department of Agriculture’s Poultry & Animal Health Lab, bird specimens collected by DNREC’s Mosquito Control Section will be submitted to the Delaware Public Health Laboratory for virus testing. From early July through mid- or late October, the Mosquito Control Section also will operate its statewide network of 23 sentinel chicken stations – which “keep watch” for WNV and for eastern equine encephalitis (EEE), another mosquito-borne viral disease which affects horses and humans.
One human case and one equine case of WNV were reported in Delaware in 2011, the first since 2008, according to the Delaware Division of Public Health. In 2003, the state had 17 reported human cases and two human fatalities from WNV, which is primarily transmitted by the common house mosquito. That year there were also six stricken horses. In 2004 and 2006, no cases of WNV were reported in humans or horses; in 2005 two human cases were reported, with no horse cases; and in both 2007 and 2008, one human case was reported.
“Mosquito Control’s effective approach to controlling mosquitoes has helped prevent significant outbreaks of West Nile virus in Delaware the last few years, with an assist from the apparently natural cycles for the occurrence of West Nile,” Dr. Meredith said, noting that some states have seen higher numbers.
For 2011, the Centers for Disease Control’s nationwide figures show 712 reported human cases of West Nile virus resulting in 43 deaths, with the most cases occurring, in descending order, in California, Arizona, Mississippi, New York, Michigan and Illinois. Regionally, 19 human cases were reported in Maryland, 15 in the District of Columbia, seven in New Jersey and six in Pennsylvania.
During its decade in Delaware, WNV may have reduced populations of some virus-prone birds such as crows, while surviving members of other bird species may have become more resistant to the virus’ effects, Dr. Meredith said. With WNV not quite as alarming to the public as when it first surfaced, the reporting of sick or dead wild birds may have diminished in importance.
Due to complicated environmental reasons, wild birds are probably better indicators of WNV early in the season from May through July than are Mosquito Control’s sentinel chickens, which become better indicators later, from August through October. Weather conditions could also impact this year’s West Nile numbers, whether found in wild birds, sentinel chickens or mosquitoes themselves, as evidence suggests outbreaks might be more severe during abnormally hot years – with the peak concern for transmission in late summer and early fall, Dr. Meredith said.
The Mosquito Control Section also will continue to document all phone reports of West Nile species of interest, but will be selective in collecting and analyzing reported birds. As the season progresses, Mosquito Control will stop analyzing specimens from areas where a number of virus-positive birds have been found, although it will continue to solicit public reporting of virus-suspect birds for these areas.
Dr. Meredith also noted that there is no cause for alarm that uncollected specimens might transmit WNV to humans or to pets that could consume a sick or dead bird. Dead birds can be left to decompose in place, or they can be buried, or bagged and disposed of in the garbage. When disposing of any dead bird, you should avoid direct skin contact by wearing gloves and/or by using a shovel.
Sick or dead birds can be reported to the Mosquito Control Section between 8 a.m. and 4 p.m., Monday through Friday, by calling Mosquito Control’s field offices:
- New Castle County and northern Kent County from Dover north (Glasgow office): 302-836-2555
- Remainder of southern Kent County and all of Sussex County (Milford office): 302-422-1512
These numbers may also be used to report intolerable numbers of biting mosquitoes to help the Mosquito Control Section determine when and where to provide control services. For more information on Delaware’s Mosquito Control programs, please call the main office at 302-739-9917, or visit http://www.fw.delaware.gov/Services/Pages/MosquitoSection.aspx.
Calls made to the field offices after business hours or during weekends or holidays can be recorded. Callers should give their name, phone number, address and a brief message. However, the public should be aware that some calls left more than 24 hours before Mosquito Control can review them – usually between Friday evening and Sunday morning – result in the bird becoming too deteriorated for virus testing.
For more information about West Nile virus in humans, please contact the Delaware Division of Public Health at 302-744-1033 or 888-295-5156. For more information about West Nile virus in horses, eastern equine encephalitis or vaccines, please contact the State Veterinarian at the Delaware Department of Agriculture at 800-282-8685 (Delaware only) or 302-698-4500.
Vol. 42, No. 203