New Jersey Department of Agriculture

Memo

To: Veterinarians

From: Nancy E. Halpern, DVM, New Jersey State Veterinarian

Date: December 12, 2008

Re: Tularemia Advisory

The New Jersey Department of Health and Senior Services (NJDHSS) reported a case of Tularemia in a New Jersey resident. Tularemia, also known as “Rabbit Fever” is a serious illness caused by the bacterium Francisella tularensis. While rare, it is endemic in New Jersey. It can occur in numerous species of domestic and wild mammals but is most common in lagomorphs (rabbits and hares) and rodents, where the affected animal is usually found dead.

Domestic livestock, pets and humans are considered accidental hosts but they can get infected and the subsequent disease can be quite serious, even fatal. Ticks are the most important vector of transmission but other biting insects can also transfer the bacterium between animals. Tularemia may also be transmitted during the ingestion of infected tissues or contaminated water or through scratches or cuts during exposure to infected animal tissue.

In many species, a clear clinical picture has not been established but the following clinical signs may occur in most species that can become infected: weakness, fever, ulcers, regional lymphadenopathy, abscesses, rigid gait and difficulty breathing. Death usually occurs within 8 to 14 days of exposure.

Tularemia in sheep usually corresponds with the regional tick season. In addition to the above listed clinical signs, sheep may also have diarrhea, frequent urination and weight loss. Death is most common in young animals while pregnant ewes may abort. While Tularemia may occur in horses, reports describing clinical signs are limited but the animals do have a history of extensive tick infestation. Infected cats experience disease ranging from non-clinical infection to sepsis and death. Dogs may become infected, however, often the clinical signs are inapparent or mild. Dogs may also serve as a reservoir for the bacterium or a maintenance host for the tick vector.

Tularemia is a reportable disease if suspected or diagnosed by a veterinarian or owner in any owned animals and must be reported to the Department of Agriculture without delay, and in any case, within 48 hours at (609) 292-3965 (N.J.A.C. § 2:2-1.1 and 1.5). Any suspected cases in wildlife should be reported to Dr. Douglas Roscoe, DEP Wildlife Pathologist at (908) 735-6398. Any questions concerning human exposure or risk should be directed to the NJDHSS Infectious and Zoonotic Disease Program at (609) 588-3121.

For more information on Tularemia in animals go to the AVMA website: http://www.avma.org/public_health/biosecurity/tularemia_facts.asp