Brucellosis is an infectious disease that spreads from animals to people — most often via unpasteurized milk, cheese and other dairy products. More rarely, the bacteria that cause brucellosis can spread through the air or through direct contact with infected animals.
Brucellosis symptoms include fever, joint pain and fatigue. The infection can usually be treated successfully with antibiotics. Treatment takes several weeks, however, and relapses are common.
While brucellosis is uncommon in the United States, the disease affects hundreds of thousands of people and animals worldwide. Avoiding unpasteurized dairy products and taking precautions when working with animals or in a laboratory can help prevent brucellosis.
Symptoms of brucellosis may show up anytime from a few days to a few months after you're infected. Signs and symptoms are similar to those of the flu and include:
Brucellosis symptoms may disappear for weeks or months and then return. In some people, brucellosis becomes chronic, with symptoms persisting for years, even after treatment. Long-term signs and symptoms include fatigue, fevers, arthritis and spondylitis — an inflammatory arthritis that affects the spine and adjacent joints.
When to see a doctor
Brucellosis affects many wild and domestic animals. Cattle, goats, sheep, pigs, dogs, camels, wild boar and reindeer are especially prone to the disease. A form of brucellosis also affects harbor seals, porpoises and certain whales. The bacteria spread from animals to people in three main ways:
Brucellosis normally doesn't spread from person to person, but in a few cases, women have passed the disease to their infants during birth or through their breast milk. Rarely, brucellosis may spread through sexual activity or through contaminated blood or bone marrow transfusions.
Brucellosis is rare in the United States. Other parts of the world have much higher rates of brucellosis infection, especially:
People who live or travel in these areas are more likely to consume unpasteurized goat cheese, sometimes called village cheese. Unpasteurized goat cheese imported from Mexico has been linked to many cases of brucellosis in the United States.
Occupations at higher risk
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:
Preparing for your appointment
If you suspect that you have brucellosis, you're likely to start by seeing your family doctor or a general practitioner. You may be referred to an infectious disease specialist.
A diagnosis of brucellosis depends on understanding if, how and when you were exposed to the bacteria that cause the disease. You can help your doctor by being prepared with as much information as possible.
What you can do
What to expect from your doctor
Tests and diagnosis
Doctors usually confirm a diagnosis of brucellosis by testing a sample of blood or bone marrow for the brucella bacteria or by testing blood for antibodies to the bacteria. To help detect complications of brucellosis, you may have additional tests, including:
Treatments and drugs
Treatment for brucellosis aims to relieve symptoms, prevent a relapse of the disease and avoid complications. You'll need to take antibiotics for at least six weeks, and your symptoms may not go away completely for several months. The disease can also return and may become chronic.
To reduce the risk of getting brucellosis, take these precautions:
Last Updated: 2010-12-10
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