Brucellosis

Definition

Brucellosis is a rare bacterial disease that causes intermittent fevers. People get this disease from domesticated animals.

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
  • Having direct contact with the secretions or excretions of infected animals
  • Inhaling the bacteria (rarely)

Risk Factors

A risk factor is something that increases your chances of getting a disease or condition. Risk factors for brucellosis include:
  • Eating or drinking unpasteurized dairy foods
  • Working with domesticated animals and livestock, especially cattle, sheep, goats, and swine, or their excretions, secretions, or carcasses

Symptoms

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

In early stages:
  • In some cases, symptoms start slowly, and may include:
  • Malaise
  • Lethargy
  • Headache
  • Muscle pain
     
  • In some cases, symptoms start suddenly, and may include:
  • Fever
  • Chills
  • Severe headache and backache
  • Nausea, vomiting, diarrhea
As it progresses, the disease causes a severe fever (104 to 105 degrees F). This fever occurs in the evening along with severe sweating. It becomes normal or near normal in the morning. The fever usually begins again at night.

This intermittent fever usually lasts 1-5 weeks. Then, symptoms usually subside or disappear for 2 days to 2 weeks. Then the fever recurs. In some patients, this fever recurs only once. In others, the disease becomes chronic, and the fever recurs, subsides, and then recurs again repeatedly over months or years.

In later stages, Brucellosis can cause:
  • Loss of appetite
  • Weight loss
  • Abdominal pains
  • Head and back aches
  • Joint pain
  • Weakness
  • Irritability
  • Insomnia
Patients usually recover within 2-5 weeks. Rarely, complications can develop. These may include inflammation of organs in the body, such as:
  • Heart
  • Brain and brain lining
  • Lymph nodes
  • Liver
  • Spleen

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam.

Lab tests may be done to look for signs of:
  • Brucella bacteria in the blood, urine, bone marrow, or tissues
  • Blood antibodies against the bacteria

Treatment

Many patients recover on their own. However, early diagnosis and treatment can reduce complications and the chance of chronic infection. Treatment may include: Antibiotics – giving more than one antibiotic at the same time is best for controlling and preventing relapses of the disease. Antibiotics are given for up to 6 weeks. Corticosteroids – these drugs, such as prednisone, can help control symptoms (especially inflammation). They are usually used for severe cases.

Prevention

The following steps can help prevent Brucellosis:
  • Avoid eating or drinking unpasteurized milk and dairy foods. If you are unsure if a dairy food is pasteurized, don’t eat it.
  • Wear rubber gloves and goggles and securely cover open wounds when handling domesticated animals including their secretions, excretions, and carcasses.
  • Wear a protective mask when dealing with brucellosis cultures in the laboratory.
  • Vaccinate young animals and livestock against the disease. There is no vaccine for humans.