Brucellosis

Definition

Brucellosis is an infectious disease caused by contact with animals carrying a bacteria called Brucella.

Alternative Names

Rock fever; Cyprus fever; Undulant fever; Gibraltar fever; Malta fever

Causes, incidence, and risk factors

Brucella can infect cattle, goats, camels, dogs, and pigs. The bacteria can spread to humans if you come in contact with infected meat or the placenta of infected animals, or if you eat or drink unpasteurized milk or cheese.

Brucellosis is rare in the United States (except in the western states).

Approximately 100 - 200 cases occur in the U.S. each year. People working in jobs requiring frequent contact with animals or meat -- such as slaughterhouse workers, farmers, and veterinarians -- are at high risk.

Symptoms

Acute brucellosis may begin with mild flu-like symptoms or symptoms such as:

• Fever
• Chills
• Excessive sweating
• Weakness
• Weight loss
• Fatigue
• Headache
• Abdominal pain
• Back pain
• Loss of appetite
• Joint pain

Classically, fever spikes occur every afternoon to levels around 104 degrees Fahrenheit. "Undulant" fever derives its name from this up-and-down fever.

Additional symptoms that may be associated with this disease:

• Muscle pain
• Swollen glands

The illness may be chronic and persist for years.

Signs and tests

• Blood culture
• Clean catch urine culture
• CSF culture
• Bone marrow culture
• Serology detecting brucellosis antigen

This disease may also alter the results of the following tests:

• Quantitative immunoglobulins (nephelometry)
• Serum immunoelectrophoresis
• Febrile/cold agglutinins

Treatment

Antibiotics are used to treat and prevent relapse of infection. Longer courses of therapy may be needed if there are complications.

Expectations (prognosis)

Relapse may occur, and symptoms may persist for years. As with tuberculosis, reactivation can occur after a long period of time.

Complications

• Bone and joint lesions
• Infective endocarditis
• Encephalitis
• Meningitis
• Chronic fatigue syndrome

Calling your health care provider

Call for an appointment with your health care provider if you develop symptoms of brucellosis.

Also, call if your symptoms worsen or do not improve with treatment, or if new symptoms develop.