Underreported Cases of Canine Brucellosis Leading to Spread of Disease

By Jennifer Coates, DVM on Jan. 25, 2016

Are you a dog breeder? If so, you should be familiar with the canine disease brucellosis, and you should be doing everything in your power to prevent its spread. New dog owners should also be aware of the basics of this disease because it can sicken both dogs and the people who come in contact with them.

The Animal and Plant Health Inspection Service (APHIS) has put together a new document called Best Practices for Brucella canis Prevention and Control in Dog Breeding Facilities. Here are some highlights.

Canine Brucellosis, caused by Brucella canis, is a significant reproductive disease of dogs. It is caused by an intracellular bacterium and often found in breeding kennels throughout the United States. B. canis is a zoonotic organism that can infect humans…. The symptoms… in humans… are frequently non-specific, and may include one or more of the following: fever (often periodic and nocturnal), fatigue, headache, weakness, malaise, chills, sweats, weight loss, hepatomegaly [enlarged liver], splenomegaly [enlarged spleen], and lymphadenopathy [enlarged lymph nodes].

There is much confusion about the disease among kennel operators and veterinarians alike. [Canine brucellosis,] while historically thought of as a disease that causes abortions, has many clinical signs that are often misinterpreted. These include but are not limited to early abortions, testicular swelling, uveitis [inflamed eyes] and spinal arthritis. The disease often exhibits no clinical signs that are obvious to the owner or veterinarian….

Natural transmission of canine brucellosis can occur by several routes. B. canis organisms are shed in the highest numbers in aborted material and vaginal discharge. Infected females transmit canine brucellosis during estrus, at breeding, or after abortion through oronasal contact of vaginal discharges and aborted materials. Shedding of B. canis may occur for up to six weeks after an abortion. Semen, seminal fluid and urine from infected males have also been documented as sources of infection…. Both males and females may shed the organism in the urine for at least three months after becoming infected. The organism can also be present in blood, milk, saliva, nasal and ocular secretions, and in the feces.

It is possible for infected females to raise infected puppies that can enter consumer markets. A 2011 survey of State Public Health Veterinarians reported that B. canis infection is a reportable disease in at least 28 states. Because the disease is reportable in many states there is a small but important “underground” that tries to avert the reporting and thus serves as a continuum for the disease.

Additionally, it is important to emphasize that in dogs it is not a curable disease, which means that carrier animals MUST be removed from the breeding population in a kennel situation [and should not be rehomed]. Attempts at treatment have been very disappointing with relapses commonly occurring. Attempted treatment can mask diagnostic testing and has been shown to be yet another important contributing factor in the spread of the disease.

For more details, I refer you to the entire report. It contains excellent information on cleaning and disinfection, the importance of wearing disposable gloves during breeding and whelping, diagnostic procedures, and how to screen and quarantine new dogs before they enter a breeding program.

If you are considering buying a puppy from a breeder, make sure you ask them about their brucellosis control measures and ask to see the results of Brucella canis testing on both the mother and father of your potential new canine family member.