DNREC has announced that its Mosquito Control Section has begun testing for possible occurrences of the West Nile virus in Delaware.


DNREC has announced that its Mosquito Control Section has begun testing for possible occurrences of the West Nile virus in Delaware. 

Horses and humans can contract West Nile Virus (WNV) and Eastern Equine Encephalomyelitis (EEE) if bitten by a mosquito carrying the virus. Delaware State Veterinarian Heather Hirst is reminding horse owners to be sure that their equines’ vaccinations are up to date.  Both diseases are potentially fatal in horses, with the most severe cases occurring in unvaccinated animals.

The viruses cannot be transmitted from horses to humans or from human to human. The viruses are normally maintained in a cycle between mosquitoes and birds. Occasionally, the EEE virus is transmitted from mosquitoes to mammals, with illness and sometimes death occurring in equines and humans.

Dr. Hirst urges horse owners to contact their veterinarian immediately if they suspect their horse may be showing clinical signs of EEE (neurological signs) or WNV. Clinical signs of EEE in horses include fever (102.5-104.5°F), anorexia, head pressing, depression or personality change, wobbling or staggering, weakness, blindness, convulsions, muscle spasms in the head and neck, and hind-limb weakness. These clinical signs are also consistent with WNV infection. Both EEE and WNV vaccines are available through your equine veterinarian.

Vaccination as a means of prevention is far more cost effective than treating the actual disease.  In some cases, infection with these preventable diseases could lead to the animal’s untimely death. Horse owners are strongly encouraged to consult with their veterinarian about vaccinating their animals against herpesvirus (rhinopneumonitis), influenza, rabies and tetanus, among others.

Also, DNREC’s Mosquito Control Section is again asking the public’s help in monitoring WNV virus by reporting sick or dead wild birds of certain species that may have contracted the virus. Only sick or dead birds of the following species: crows, blue jays, cardinals, robins, and hawks or owls, plus clusters of five or more sick or dead wild birds of any species, should be reported by calling Mosquito Control at 739-9917. Bird specimens should have been dead for less than 24 hours and not appear to have died or been killed by other obvious causes.

For human health questions about EEE or West Nile virus, call the Delaware Division of Public Health at (888) 295-5156 or 744-1033.

For animal-related questions about EEE or West Nile, call the Delaware Department of Agriculture at (800) 282-8685 (Delaware only) or 698-4500, and ask for the Poultry and Animal Health section.

For questions about the state’s Mosquito Control program or mosquito biology, call DNREC at 739-9917.