METHODS: Brucella suis is a federal select agent and suspect isolates are required to be reported and submitted to approved reference laboratories. Veterinarians also frequently report serologic positive dogs to health or agriculture officials. Testing of domestic animals suspected to be linked to human illnesses is also recommended by DOH. Cultures were speciated or serologically typed at state public health or agriculture laboratories.
RESULTS: Three dogs were culture positive for Brucella suis. Four were serologically positive for smooth Brucella species (includes B. suis) and negative for rough Brucella species (includes Brucella canis). Four cases were identified because the dog was clinically ill and included two cases of unilateral orchitis, one discospondylitis infection, and one dog with an infected bone plate. Three dogs were identified because of a link to a single human infection. One of these dogs had reportedly lost a litter of pups a few months prior to testing positive for Brucella. All dogs spent considerable time outside at some point in their lives and three were used for hunting feral swine. Only two of the seven had been neutered or spayed at the time of diagnosis. One of the hunting dog’s owners reported his hunting buddy was diagnosed with brucellosis which was confirmed. Four laboratorians were exposed to canine B. suis isolates. During one investigation veterinary surgical staff also underwent exposure assessment with no exposure identified. One illness in a child may have been linked to infected dogs.
CONCLUSIONS:
- Canine brucellosis is probably underdiagnosed in areas with endemic feral swine brucellosis.
- Brucellosis infections in dogs and other animals pose a potential exposure risk to laboratorians and veterinary staff; these groups should be targeted for prevention messaging.
- The risk to dog owners is not well characterized; however most human B. suis infections in Florida report direct contact with feral swine rather than dog contact with no swine interaction.