New Jersey Department of Agriculture – Division of Animal Health MEMO: Update Concerning EEE and WNV Positive Horses in New Jersey in 2017

On October 24, 2017 two more New Jersey horses tested positive for Eastern Equine Encephalitis (EEE) and both were euthanized as a result of the infection. The ten and eleven year-old geldings were both located in Cape May County. To date, five New Jersey horses have tested positive for EEE and two New Jersey horses have tested positive for West Nile Virus (WNV). In all cases, the positive horses were either not vaccinated, were not current on vaccination, had an unknown vaccination history, or did not receive the necessary booster following the initial vaccination. Thus far, all positive horses have been located in the southern portion of the state:

Atlantic County: 1 EEE+
Cape May County: 2 EEE+
Cumberland County: 2 EEE+
Gloucester County: 1 WNV+
Salem County: 1 WNV+

Both EEE and WNV are viral diseases that affect horses’ neurological systems and are transmitted by mosquito bite. EEE and WNV are serious diseases that cause inflammation of the brain tissue. In addition, EEE has a significantly higher death rate than WNV with a mortality rate of up to 90%. As indicated above, horses fully vaccinated for EEE and WNV are less likely to contract these deadly diseases. Effective equine vaccines for WNV and EEE have been available for several years.

For more information about EEE and WNV in horses, visit the New Jersey Department of Agriculture website at:

EEE and WNV, like other viral diseases affecting horses’ neurological systems, must be reported to the state veterinarian within 48 hours, and a neurologic disease worksheet must be completed for each case reported. The worksheet is available at the following website and once completed can be faxed to the Division.

The NJDA – Animal Health Diagnostic Laboratory (AHDL) is available to assist with EEE, WNV, and EHV-1 testing. If the horse is located in NJ, the EEE and WNV testing is provided at no cost to the submitter as the AHDL receives funding from the State Mosquito Control Commission to perform the testing.

EEE PCR (no charge)
1 ml whole blood PTT*/CSF**/brain tissue
ELISA (no charge)
1 ml serum, w/cold pack
2-3 days
WNV PCR (no charge)
Whole blood PTT */CSF**/brain tissue
ELISA (no charge)
1 ml serum, w/cold pack
2-3 days
EHV-1 Neurologic PCR ($50.00)
Whole blood PTT/Nasal swab, brain tissue
EHV-1 SN titer ($15.00)
1 ml serum, w/cold pack
2-4 days

*PTT-purple top tube **spinal fluid

Contact Dr. Amar Patil (609) 406-6999 or via email at

Division of Animal Health
Phone: (609) 671-6400
Fax: (609) 671-6413
Animal Health Diagnostic Laboratory
Phone: (609) 406-6999
Fax: (609) 671-6414


Mail laboratory specimen(s) and laboratory submission form to:

(If sent via courier service):NJ Department of Agriculture
Animal Health Diagnostic Laboratory
NJPHEAL, 3 Schwarzkopf Drive
Ewing, NJ 08628
(If sent via U.S. Postal Service):NJ Department of Agriculture
Animal Health Diagnostic Laboratory
P.O. Box 330
Trenton, NJ 08625