DOVER – DNREC’s Mosquito Control Section within the Division of Fish & Wildlife is seeking the public’s help in monitoring West Nile virus in Delaware by reporting sick or dead wild birds that may have contracted the virus. West Nile virus (WNV) is a mosquito-borne disease of considerable concern to human health and to owners of unvaccinated horses.
The Mosquito Control Section requests that the public report sick or dead birds of the following species only: crows, blue jays, cardinals, robins, 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 from other obvious causes. Mosquito Control also notes that uncollected dead wild bird specimens are very unlikely to transmit WNV to humans or pets.
“We are again tracking when and where West Nile virus might appear in Delaware this year and monitoring its possible spread throughout the state,” said Dr. William Meredith, Mosquito Control Section administrator, DNREC Division of Fish & Wildlife. “Our sampling strategy is to collect and test birds from now into late September.”
Birds collected by DNREC are processed by the Delaware Department of Agriculture’s Poultry & Animal Health Lab, and then submitted to the Division of Public Health (DPH) Laboratory for virus testing. From July through mid- to late-October, DNREC’s Mosquito Control Section also operates a statewide network of about 20 sentinel chicken stations in prime mosquito areas. The DPH lab tests blood samples from the sentinel chickens for WNV and Eastern equine encephalitis (EEE), another mosquito-borne viral disease that affects humans and horses. The results help indicate where WNV or EEE has been transmitted by mosquitoes from wild bird hosts to other animals, possibly leading to an increased risk of exposure for humans or horses. Neither WNV nor EEE can be transmitted between horses or from horses to people.
The period of greatest concern for disease transmission for WNV and EEE is late summer and early fall. WNV is transmitted to humans primarily by the common house mosquito, and possibly by the Asian tiger mosquito. The disease first appeared in Delaware in 2001. Last year, Delaware had one human case and two equine cases, with the last cases of EEE detected in two horses in 2013. Nationwide, the Centers for Disease Control (CDC) logged 2,022 reported human cases of WNV last year resulting in 121 deaths, 10 of which occurred in our region.
Four other mosquito-borne diseases of concern that can occur in Delawareans are malaria, dengue fever, and chikungunya and Zika viruses. Cases of these four diseases are almost always found in travelers returning from tropical or sub-tropical regions where these illnesses are more prevalent. None involve wild birds as hosts, but rather are transmitted by mosquitoes from person-to-person.
To report sick or dead birds, call Mosquito Control’s field offices between 8 a.m. and 4 p.m., Monday through Friday:
New Castle County and Kent County from Dover north, Glasgow office: 302-836-2555
Remainder of Kent County and Sussex County, Milford office: 302-422-1512
Residents also are encouraged to call to report intolerable numbers of biting mosquitoes and request control services. Voicemail may be left after hours, or on weekends or holidays.
For more information, call Delaware Mosquito Control’s main office at 302-739-9917, or click Delaware Mosquito Control.
For more information about West Nile virus in humans, call the Delaware Division of Public Health at 302-744-4990 or 888-295-5156.
For more information about West Nile virus in horses, Eastern equine encephalitis, or vaccines, call the Delaware Department of Agriculture’s Poultry and Animal Health Section at 800-282-8685 (Delaware only) or 302-698-4500.