Brucellosis is a bacterial disease of animals that can affect people. In general, the disease in animals causes reproductive failure, such as abortion or the birth of unthrifty off-spring in females and infection of the reproductive tract and sterility in males.
There are several different species of Brucella, of which only two occur in Australia: Brucella ovis and Brucella suis.
The principal animal hosts for the different Brucella species are:
- Brucella ovis - sheep. Occurs in Australia
- Brucella suis - pigs. Occurs in Australia
- Brucella abortus - cattle. Exotic to Australia
- Brucella melitensis - goats. Exotic to Australia
- Brucella canis - dogs. Exotic to Australia
- Brucella ceti - seals
- Brucella pinnepedialis - whales, dolphins and porpoises.
Brucella abortus no longer occurs in Australia as a result of a national eradication program between 1970 and 1989. In most countries it is responsible for a highly contagious disease in cattle resulting in late-term abortion and infertility. The disease is also a serious zoonosis, causing undulant fever in humans.
Brucella melitensis can affect most domestic animals, but goats and sheep are especially susceptible. The bacteria causes a severe debilitating disease in people known as Malta fever. B. melitensis is common in goats in Mexico where it is the major cause of human brucellosis. It occurs in small ruminants in Latin America, southern Europe, the Middle East, Central Asia, and Africa. It does not occur in Australia.
Brucella canis is known to cause disease only in dogs although antibodies to this organism have been found in other carnivores. B. canis is zoonotic, but human infections seem to be uncommon. B canis has been reported in many countries, the Americas, Europe and Asia. It does not occur in Australia.