Brucellosis is a bacterial infection.


The bacteria infects livestock such as sheep, goats, cattle, deer, elk, and pigs. Humans get the bacteria from infected livestock by:

  • Eating or drinking animal products
  • Inhaling the bacteria
  • Contact through cuts in your skin or fluids in your eye

Rarely, it can pass between people by:

  • Breastfeeding—from an infected mother to her baby
  • Sexual contact
  • A transplant from an infected donor

Risk Factors

Your risk may be higher if you:

  • Work with livestock, their waste products, bodily fluids, or carcasses
  • Eat or drink unpasteurized dairy products
  • Eat undercooked meat products
  • Live in or travel to places where the bacteria is common


In most cases, symptoms appear within 2-4 weeks after infection. However, symptoms can appear from 5 days to several months after.

Early symptoms may involve:

  • General feeling of illness—malaise
  • Fatigue
  • Headache
  • Muscle or joint pain
  • Fever
  • Chills
  • Severe headache and backache
  • Nausea, vomiting, or diarrhea
  • Rash

Brucellosis causes a high fever (104°F-105°F). It goes up in the evening and returns to normal by morning. Evening fevers can also cause severe sweating. This cycle lasts 1-5 weeks. In some people, the fever will return. It may do so once or many times over months or years.

In addition to the list above, late symptoms may involve:

  • Loss of appetite
  • Weight loss
  • Belly pain
  • Weakness
  • Irritability
  • Insomnia

Serious problems may involve:

  • Abscesses within the liver or spleen
  • Enlargement of the liver, spleen, or lymph nodes
  • Inflammation and infection of organs in the body, such as:
  • Scrotal swelling

Women who have the infection early in their pregnancy may have a higher risk of miscarriage.

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Your doctor will ask about your symptoms, and healthl and travel history.

You may also have:

  • A physical exam
  • Blood tests
  • Bone marrow tests
  • Lumbar puncture to test the fluid that surrounds the brain and spinal cord
  • Tissue tests
  • Imaging tests such as an MRI scan


Brucellosis goes away on its own in most people. Finding it early and starting care will lower the chance of long-term health problems.

Care include:

  • Antibiotics to treat the infection. You may need to take them for up to 6 weeks.
  • Surgery to treat abscesses or infections that don't go away after taking antibiotics.


To help lower your chances of brucellosis:

  • Avoiding unpasteurized milk and dairy foods. If you aren’t sure if food or drink is safe, avoid it.
  • Wearing rubber gloves and goggles when working with livestock, their bodily fluids, or carcasses. Cover open sores on your skin.
  • Wearing a protective mask when working with brucellosis cultures.
  • Keeping up with livestock vaccines. Talk to a veterinarian or your local health department for help.

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