West Nile Virus detected in sentinel chicken

December 12, 2022

West Nile Virus detected in sentinel chicken

MOBILE, Ala. – A sentinel chicken used by the Mobile County Health Department (MCHD) to detect mosquito-borne diseases in the community has tested positive for West Nile Virus (WNV).

WNV has been confirmed by laboratory results, according to Dr. Kevin P. Michaels, Health Officer for Mobile County. The coop is located in the 36541 ZIP Code area.

Vector Services has had sentinel chickens in seven coops test positive for viruses this year. Six have been for WNV while a seventh was positive for Eastern Equine Encephalitis (EEE).

Humans with WNV and other mosquito-borne diseases often have symptoms of high fever, severe headache, nausea, stiff neck, confusion, muscle weakness, paralysis, disorientation, and seizures that are severe enough to require medical attention.

The risk of encephalitis spread by mosquitoes is highest from August through the first freeze in the fall. MCHD’s Vector Services will increase spraying and conduct door-to-door surveys in the immediate areas. Inspectors will also attempt to trap adult mosquitoes and test them for the presence of WNV.

Blood is drawn from the sentinel chickens every Monday by Vector Services, and the samples are sent to a lab in Tampa, Florida. The results of the tests are made available later in the week.

Health officials warn that it is extremely important that people taking part in outdoor activities make every effort to reduce their exposure to mosquitoes. Recommendations include:
• Use an Environmental Protection Agency-registered repellent with DEET.
• Wear long-sleeved shirts and long pants.
• Stay and sleep in places with air conditioning or window and door screens.
• Remove standing water around your home.

WNV is transmitted from bird to mosquito to bird during the transmission cycle. Mosquitoes can spread these viruses by feeding on the blood of infected birds and then biting another host animal or mammal, such as a human or a horse.

Although humans and horses can become ill from the infection, the diseases cannot be spread from people or horses. The likelihood of transmission to humans and horses can be decreased by personal mosquito avoidance and the use of a WNV vaccine in horses. There is no vaccine available for humans.

For approximately 30 years, MCHD’s Vector Services has monitored encephalitis in sentinel poultry flocks strategically placed in 13 coops throughout the county to detect the presence of viruses carried by mosquitoes. Mosquitoes also are trapped and tested for WNV, EEE, and St. Louis Encephalitis.

To report an issue with mosquitoes, call Vector Services at 251-690-8124. To learn more about the department, you may visit https://mchd.org/vector-control. From there, you can find a link and a QR code to access the new online portal for ordering services to deal with mosquitoes and rodents.