Swine brucellosis is a venereal disease that infects pigs during mating. Farmed domestic pigs have not had any new cases of swine brucellosis in Queensland since 1991. In feral pigs, however, the disease hasn't been eradicated (completely removed). Breeding stock should be purchased only from a 'clean' pig herd.
Swine brucellosis is an infectious disease of swine caused by Brucella suis (B. suis) biovars 1 or 3. Swine exposed to B. suis develop a bacteremia (bacterial infection in the blood). Infection can then localize in various tissues.
Brucellosis is an infection that can be transmitted to humans from some animals such as cows, sheep, goats and pigs. While this disease is common in many parts of the world, it is rare in Australia.
Epidemiology. Brucella suis usually is transmitted to susceptible swine through direct contact with infected swine. The route of exposure ordinarily is through the alimentary or genital tract. Pigs often are infected by ingesting aborted fetuses, fetal membranes or fluids discharged at the time of abortion.
Clinical signs
Infected boars may develop swollen testicles and there may be reproductive failure. There may be signs of incoordination and hind limb paralysis. Sows may abort and develop sterility. Piglets may be born dead or weak.
Rare or undercooked meat should not be eaten; thoroughly cook meat to avoid contracting pathogens. Raw feral pig meat and offal should not be fed to dogs as dogs can be infected with swine brucellosis. Dogs infected with swine brucellosis can also transmit the disease to humans.
Australia is free of Brucella abortus, Brucella melitensis and Brucella canis. Bovine brucellosis is caused by Brucella abortus and was eradicated from Australia in 1989 as a result of a national eradication program.
Prevention and Control of Brucellosis in Pigs
There is no vaccine for brucellosis in swine, and no practical recommendations can be made for treatment. Control is based on test and removal of infected breeding animals.
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.
How do dogs become infected? Brucellosis (Brucella suis) has been detected in dogs that have been pig-hunting and dogs that have been fed raw feral pig meat. It is possible that a dog may be infected through contact with an infected dog or its body fluids – for example when bred/mated and at the time of birth.
People with brucellosis may develop fever, sweats, headaches, back pains, and physical weakness. In severe cases, the central nervous system and the lining of the heart may be affected. One form of the illness may also cause long-lasting symptoms, including recurrent fevers, joint pain, and fatigue.
What are the signs of brucellosis? There is no effective way to detect infected animals by their appearance. The most obvious signs in pregnant animals are abortion or birth of weak calves. Milk production may be reduced from changes in the normal lactation period caused by abortions and delayed conceptions.
Swine brucellosis is a venereal disease that infects pigs during mating. Farmed domestic pigs have not had any new cases of swine brucellosis in Queensland since 1991. In feral pigs, however, the disease hasn't been eradicated (completely removed). Breeding stock should be purchased only from a 'clean' pig herd.
The most common ways that bacteria spread from animals to people are by: Eating raw dairy products. Brucella bacteria in the milk of infected animals can spread to humans in unpasteurized milk, ice cream, butter and cheeses. The bacteria can also be transmitted in raw or undercooked meat of infected animals.
Brucellosis, also known an undulant fever, is an infectious disease caused by bacteria. People can get the disease when they have contact with infected animals or raw animal products. Brucellosis is not usually fatal to people, but may result in long-term illness and lasting health problems even after treatment.
Many reports have indicated that Brucella species are readily killed by most of the commonly available disinfectants including hypochlorite solutions, 70% ethanol, isopropanol, iodophores, phenolic disinfectants, formaldehyde, glutaraldehyde and xylene [5,10].
Disinfectants with bleach, at least 70 percent ethanol, iodine/alcohol solutions, glutaraldehyde or formaldehyde will effectively kill the bacteria. How is canine brucellosis prevented?
Depending on the timing of treatment and severity of illness, recovery may take a few weeks to several months. Death from brucellosis is rare, occurring in no more than 2% of all cases. Generally, the antibiotics doxycycline and rifampin are recommended in combination for a minimum of 6-8 weeks.
Pseudorabies. Pseudorabies (also known as Aujeszky's disease or "mad itch") is a viral disease most prevalent in swine, often causing newborn piglets to die.
No special diet is required for the treatment of brucellosis. Discuss with patients the importance of consuming pasteurized milk and milk products and avoiding other possible sources of infection.
Most cases are caused by ingesting unpasteurized milk or cheese from infected goats or sheep. Brucellosis is one of the most widespread zoonoses transmitted by animals and in endemic areas, human brucellosis has serious public health consequences.
Harmful organisms and pathogens, carried by feral swine, which can infect humans include diseases such as leptospirosis, toxoplasmosis, brucellosis, tularemia, trichinellosis, swine influenza, salmonella, hepatitis and pathogenic E. coli.
Person-to-person spread of brucellosis is extremely rare. Infected mothers who are breast-feeding may transmit the infection to their infants. Sexual transmission has been rarely reported. While uncommon, transmission may also occur via tissue transplantation or blood transfusions.