Contact: Joanna Wilson, Public Affairs Office, 302-739-9902.
First finding of West Nile Virus in wild birds reported for 2012
DOVER (July 16, 2012) – An American crow submitted to the Delaware Public Health Laboratory by Tri-State Bird Rescue in Newark on July 10 has tested positive for West Nile virus (WNV), as reported by the Lab on July 13. The bird was collected in the Newark area. WNV is a mosquito-borne disease that affects humans and horses.
“The Mosquito Control Section has responded to this West Nile virus-positive bird result by increasing our mosquito surveillance-and-monitoring activities in the Newark area, and we will take appropriate follow-up mosquito control actions as warranted,” said DNREC Mosquito Control Section Administrator Dr. William Meredith.
According to Dr. Erica Miller, staff veterinarian at Tri-State, when the facility receives birds suspected of having West Nile, they are treated and kept in isolation. “Some pull through and survive,” she said, while others, as in the case of the crow, are too sick and either die or are humanely euthanized. In cases where West Nile is suspected, Tri-State sends tissue samples to the DPH Lab, Dr. Miller said.
To date, no other findings of West Nile virus have been reported this year in Delaware, the virus not having been detected by the Mosquito Control Section’s statewide network of 23 sentinel chicken monitoring stations in operation since early July, in any wild birds collected by or submitted to Mosquito Control, or in any humans or horses.
Eastern equine encephalitis (EEE) virus, another mosquito-borne disease that also affects humans and horses, has not been detected yet in 2012. However, peak activity in the mid-Atlantic region for both WNV and EEE typically occurs from about the first week in August through the second week in October, so findings in host wild birds or mosquitoes could occur and increase over the next several weeks, with possible transmission to humans or horses.
“West Nile virus has been found in Delaware every year since 2001. The finding is not cause for alarm,” Meredith said. “However, it is a good reminder to take common-sense precautions against mosquito bites, including wearing long-sleeved shirts and long pants when outdoors in mosquito-prone areas, applying insect repellent containing 10-30 percent DEET in accordance with all label instructions, and avoiding mosquito-infested areas or times of peak mosquito activity around dusk, dawn or throughout the evening.”
In addition, to reduce mosquito-breeding, Meredith added that people should drain or remove items from their yards that collect water, such as buckets, birdbaths, rain barrels, old tires, flower pot liners, depressions in tarps covering boats, clogged rain gutters, and unused swimming pools.
An effective equine vaccine is now available to protect horses from WNV and EEE, but a human vaccine has not yet been approved. About 80 percent of all people infected by West Nile experience no symptoms. About 20 percent of those who become ill with the virus typically have only mild symptoms, similar to a “summer flu.”
Less than 1 percent of humans infected with West Nile experience more serious symptoms such as sudden onset of severe headache, high fever, stiff neck, confusion, muscle weakness, and occasionally skin rash on the trunk and swollen lymph glands. Individuals with these more severe symptoms should see their physician immediately, since between 3 and 15 percent of all severe cases can result in permanent brain and nerve problems or death. People over the age of 50 and some immuno-compromised persons such as transplant patients have the highest risk for becoming severely ill when infected with WNV and should take special care to avoid mosquito bites.
Sick or dead wild birds for the species of interest (crows, blue jays, cardinals, robins, hawks and owls) in monitoring for West Nile virus can be reported to the Mosquito Control Section from Monday through Friday between 8 a.m. and 4 p.m. by calling the Glasgow Office, serving New Castle and northern Kent counties north of Dover, at 302-836-2555, or the Milford Office, serving Sussex and southern Kent counties south of Dover, at 302-422-1512.
Callers can leave a message after business hours or during weekends or holidays, including name, phone number, address and a brief message about the finding. However, the public should be aware that birds reported more than 24 hours before Mosquito Control can review them may be too deteriorated for virus testing.
The Mosquito Control phone numbers above should also be used for citizens to report intolerable numbers of biting mosquitoes. The section uses this information to help determine when and where to provide control services.
For more information about mosquito biology/ecology and mosquito control, contact the Mosquito Control Section’s Dover office at 302-739-9917.
For more information about West Nile virus in humans and related medical issues, contact the Division of Public Health at 888-295-5156.
For more information about West Nile virus in horses and equine vaccines, contact the Department of Agriculture at 302-698-4500 or 800-282-8685 (toll-free, Delaware only).
Tri-State Bird Rescue is a non-profit facility in Newark that treats and rehabilitates sick and injured wild birds. For more information, contact Tri-State at 302-737-9543 or visit www.tristatebird.org.
Vol. 42, No. 264