melitensis causes the most severe cases of brucellosis and is the most prevalent worldwide. B melitensis is acquired by exposure to animals or animal products. Ingestion of unpasteurized goat milk and related dairy products is the main route by which B. melitensis is transmitted to humans.
Worldwide, Brucella melitensis is the most prevalent species causing human brucellosis, owing in part to difficulties in immunizing free-ranging goats and sheep.
*Three types of the bacteria that cause brucellosis – Brucella abortus, Brucella melitensis and Brucella suis – are designated as select agents. This means that they have the potential to be developed as bioterrorism agents due to their ability to undergo aerosolization.
Of the 4 Brucella species known to cause disease in humans (B abortus, B melitensis, B canis, B suis), B melitensis is thought to be the most virulent and causes the most severe and acute cases of brucellosis; it is also the most prevalent worldwide.
Brucellosis is an infectious disease caused by bacteria. People can get the disease when they are in contact with infected animals or animal products contaminated with the bacteria. Animals that are most commonly infected include sheep, cattle, goats, pigs, and dogs, among others.
Brucellosis can affect almost any part of your body, including your reproductive system, liver, heart and central nervous system. Chronic brucellosis may cause complications in just one organ or throughout your body. Possible complications include: Inflammation of the inner lining of the heart chambers (endocarditis).
Brucellosis can be diagnosed in a laboratory by finding bacteria in samples of blood, bone marrow or other bodily fluids. Serological tests can also be done to detect antibodies against the bacteria. Learn more about what can be done to help confirm diagnosis of this disease.
Bovine brucellosis (B. abortus) was eradicated from the Australian cattle herd in 1989 and is presently considered an exotic animal disease in Australia.
Brucella melitensis is the most pathogenic; B abortus is associated with less frequent infection and a greater proportion of subclinical cases. The virulence of B suis strains for humans varies but is generally intermediate.
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.
Brucellosis, also known as “undulant fever”, “Mediterranean fever” or “Malta fever” is a zoonosis and the infection is almost invariably transmitted by direct or indirect contact with infected animals or their products. It affects people of all age groups and of both sexes.
Brucellosis can also cause long-lasting or chronic symptoms such as recurrent fevers, joint pain, testicular swelling, heart infections, nervous system impairment, depression, and fatigue. Death from brucellosis is rare.
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.
Certain groups of people are at higher risk of getting brucellosis, including people who work in slaughterhouses or the meat-packing industry, veterinarians, laboratory workers, and hunters.
Fever is the most common symptom and sign of brucellosis, occurring in 80-100% of cases. It is intermittent in 60% of patients with acute and chronic brucellosis and undulant in 60% of patients with subacute brucellosis.
Brucellosis affects males and females in equal numbers. The disorder is rare in the United States since pasteurization of milk is routine and cattle are vaccinated against this disease.
Brucella abortus, Brucella suis, Brucella melitensis, Brucella ovis, Brucella canis, and Brucella neotomae are the species of Brucella and their natural reservoirs.
Lymph nodes, spleen, lungs, and the reproductive organs, including placenta, testicular and mammary glands, are well-known target organs for Brucella infection [27].
Whereas Salmonella envelopes are effective barriers that allow growth in the presence of bile salts, Brucella envelopes are permeable to hydrophobic compounds.
This is a serious zoonotic disease causing illness in people. Brucella abortus no longer occurs in Australia as a result of a national eradication program between 1970 and 1989. Brucella ovis infection causes disease and infertility in sheep, but does not affect people.
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.
See a GP if you have symptoms of brucellosis and:
you've had unpasteurised milk or dairy products. you've eaten raw or undercooked meat. you work closely with farm animals.
High fever (over 103 degrees Fahrenheit/39.4 degrees Celsius). Severe abdominal (stomach) pain. Confusion or other mental changes.