Brucellosis is an illness caused by infection with a type of bacteria (Brucella) that is spread to humans from infected animals including feral pigs, dogs, cattle, goats, sheep and camels. It occurs worldwide but is uncommon in Australia.
Brucellosis may come on suddenly or quite gradually. It can cause a continuous or intermittent fever, headache, weakness, drenching sweats, chills, joint and muscle pain, weight loss and generalised aches. The severity and duration of symptoms can vary greatly between people.
Symptoms usually start 5 – 60 days after a person has been infected. The disease may last for several days, months or occasionally last for a year and may recur even after appropriate treatment.
Effective treatment usually involves a long course (at least six weeks) of a combination of oral and intravenous antibiotics. Relapses may occur and further treatment will be needed to treat this. If symptoms persist your doctor should be consulted.
Different types of Brucella can occur in different animals. Around the world, Brucella bacteria are carried by cattle, sheep, goats, pigs, dogs, camels, buffalo, reindeer, marine and other animals. In Australia, Brucella is no longer found in cattle and has never been found in sheep or goats. There have been cases of Brucellosis identified in dogs in northern New South Wales.
The most common source of human infection in Queensland is feral pigs. If an animal is infected, the bacteria can be present in the urine, faeces, blood, vaginal discharges, aborted animal foetuses and especially in the placenta and afterbirth. Brucellosis is also considered an occupational disease because of a higher incidence in people working with animals (abattoir cases).
The bacteria are easily spread to humans through a break in the skin (open cut or sore), or by inhalation during work in dusty yards. People may also be infected by eating and drinking raw milk and dairy products from infected animals. Person to person spread is extremely rare.
There is no human vaccine for protection against brucellosis. The most important means of preventing disease in humans is to take precautions when coming into contact with animals or animal products that may be infected.
If you are likely to come into contact with potentially infected animals (especially feral pigs):
- cover all cuts or abrasions with waterproof dressings
- use gloves, overalls and face masks when slaughtering animals or handling carcasses
- thoroughly wash hands and arms in soapy water after handling animals or carcasses
- take particular care when handling or disposing of birth products, such as placentas vaginal discharges, aborted foetuses or the mother animal itself
- wash off all urine, faeces, blood and other body fluids and thoroughly clean all working areas.
Other preventive measures include:
- minimise dust and rodents in slaughter areas and in animal housing areas
- do not slaughter or cut up feral pig carcasses in areas also used for handling meat for human consumption
- do not allow domestic animals to eat raw feral pig meat or other, as this may infect them with brucellosis
- avoid drinking unpasteurised milk or eating dairy products produced from unpasteurised milk, particularly if travelling overseas. Boiling raw milk is effective when pasteurisation is not possible.
For further information, please contact your local doctor, health centre or nearest public health unit; or call 13 HEALTH (13 43 25 84) 24 hours a day 7 days a week for the cost of a local call.
Heymann, D. (Ed). 2015. Control of Communicable Diseases Manual, 20th edition. Washington, DC: American Public Health Association.