Brucellosis in pigs is an infectious and contagious disease caused by the bacteria, Brucella suis. The disease spreads in semen during breeding and by ingesting, inhaling or eye contact with bacteria in milk, reproductive fluids, placenta, aborted fetuses and urine. The disease primarily occurs in adult pigs which show non-specific infertility, abortion or lack of sexual drive. Boars can show signs of orchitis, lameness, arthritis, abscesses and posterior paralysis. There is no treatment for the disease and no effective vaccine. Swine brucellosis is infectious and can be a dangerous debilitating in humans.
As with Pseudorabies our domestic swine herds are “free” of brucellosis but feral swine populations on all of the major islands are infected. The same biosecurity measures employed to prevent infection of domestic swine with pseudorabies also work to prevent brucellosis infections. However once infection is established in a swine herd brucellosis is very difficult to eradicate and typically requires complete depopulation of an infected herd. Swine brucellosis can infect other domestic animals including cattle, horses, dogs but infections are not very common. Humans, particularly hunters, those that raise feral swine in captivity, veterinarians and slaughter plant workers are all at higher risk for contracting swine brucellosis if they are exposed to infected feral swine. Those individuals that have contact with feral swine should take precautions and wear protective equipment to prevent contaminating themselves that can result in an infection. Any individual who experiences protracted flu like symptoms after exposure to feral swine should see their physician. On the major Hawaiian Islands infection rates are low on Kauai and Molokai and in the range of 10 to 25 percent on the other islands.
Link to USDA information: https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/swine-disease-information/swine-brucellosis#:~:text=Swine%20brucellosis%20is%20usually%20spread,transmit%20the%20disease%20during%20mating.