Definition | Causes | Risk Factors | Symptoms | Diagnosis | Treatment | Prevention

Definition

Brucellosis is a rare bacterial disease that causes fevers to come and go. Brucellosis is mainly spread among animals. People can also get this disease from domesticated animals. It results in flu-like symptoms and may cause long-lasting symptoms.

Causes

Brucellosis is caused by the bacterium Brucella. This bacterium infects domesticated animals. It can be spread to humans through:

  • Drinking unpasteurized milk
  • Eating dairy foods from infected cows, sheep, or goats
  • Inhaling the bacteria
  • Breastfeeding (passed from mother to infant)
  • Sexual transmission
  • Tissue transplantation

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Risk factors for brucellosis include:

  • Working with domesticated animals and livestock, especially sheep, goats, cattle, deer, elk, and pigs, or their waste products, bodily fluids, or carcasses
  • Sex: male (possibly due to occupational exposure among farmers, ranchers, veterinarians, people working in tanneries, and slaughterhouse workers)

Symptoms

Symptoms of brucellosis usually appear within two weeks of infection. Symptoms can appear from five days to several months after infection.

In the early stage, symptoms may include:

As it progresses, brucellosis causes a severe fever (104° F to 105° F). This fever occurs in the evening along with severe sweating. It becomes normal or near normal in the morning, and usually begins again at night.

This on and off fever usually lasts 1 to 5 weeks. After 5 weeks, symptoms usually improve or disappear for two days to two weeks. Then the fever recurs. In some patients, this fever returns only once. In others, the disease becomes chronic, and the fever returns, lessens, and then recurs again over months or years.

In later stages, brucellosis can cause:

  • Loss of appetite
  • Weight loss
  • Abdominal pain
  • Headache
  • Backache
  • Joint pain
  • Weakness
  • Irritability
  • Insomnia

Patients usually recover within 2 to 5 weeks. Rarely, complications can develop. These may include:

  • 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

Endocarditis

Bacterial endocarditis, aortic valve
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Brucellosis is also believed to cause a high rate of miscarriage during early pregnancy in infected women.

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done.

Your doctor may need to test your bodily fluids. This can be done with:

  • Blood tests
  • Urine tests
  • Bone marrow tests
  • Tissue tests

Your doctor may need pictures of your bodily structures. This can be done with:

Treatment

Many patients recover from brucellosis on their own. However, early diagnosis and treatment can reduce the risk of complications and infection. Talk with your doctor about the best treatment plan for you. Treatment options include:

Your doctor may prescribe one or more antibiotics (usually doxycycline and rifampin) to control and prevent brucellosis. Antibiotics are given for up to six weeks.

Prevention

To help reduce your chances of getting brucellosis, take the following steps:

  • Avoid eating or drinking unpasteurized milk and dairy foods. If you are unsure if a dairy product is pasteurized, don’t eat it.
  • Wear rubber gloves and goggles, and securely cover open wounds when handling domesticated animals including their fluids, waste products, or carcasses.
  • Wear a protective mask when dealing with brucellosis cultures in a laboratory.
  • Have cattle and bison that live in areas heavily infected with brucellosis vaccinated by an accredited veterinarian or government health official. The vaccine contains a live virus and is dangerous to humans. For best results, calves should be vaccinated when they are 4-6 months old. There is no brucellosis vaccine for humans as of yet.