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Brucellosis is a reportable disease in Oklahoma.  Brucellosis, also called undulant fever, is an infectious disease caused by various species of the bacteria Brucella.  The disease primarily affects animals, but occasionally causes disease in humans who have contact with infected animals, or who consume food products from infected animals.  Brucellosis typically infects sheep, goats, cattle, deer, elk, pigs, dogs, and several other mammals.  Brucellosis is rare in the US, but continues to be common in countries where animal disease control programs have not reduced the amount of disease among animals.

Brucellosis can cause a range of symptoms that may include fever, sweats, headache, back pain, and physical weakness.  Severe infections of the central nervous system or lining of the brain may occur.  Brucellosis can also cause long-lasting symptoms that include recurrent fever, joint pain, and fatigue.

Humans are generally infected in one of three ways: consuming food or beverages that contain Brucella bacteria, breathing in the organism, or having the bacteria enter the body through breaks in the skin.  Direct person-to-person spread of brucellosis is extremely rare.  The most common way to be infected is by eating or drinking milk products from infected animals.  When female sheep, goats, cows, or camels are infected, their milk becomes contaminated with the bacteria.  If the milk is not pasteurized, these bacteria can be transmitted to persons who drink the milk or consume dairy products made from the milk.  Inhalation of Brucella organisms is not a common route of infection, but it can be a significant hazard for people in certain occupations, such as those working in laboratories.  Infection through breaks in the skin may occur in slaughterhouse or packing plant workers, those assisting an animal birth, or veterinarians handling infected animals and carcasses.  Hunters may be infected through skin wounds or by accidentally ingesting the bacteria after butchering deer, elk, moose, or wild pigs.

Brucellosis is diagnosed in a laboratory by finding Brucella organisms in a sample of blood or bone marrow.  Also, blood tests can be done to detect antibodies against the bacteria.  Treatment for brucellosis consists of a 6-week course of antibiotics prescribed by a physician.  Usually, the antibiotics doxycycline and rifampin are used in combination for 6 weeks to prevent reoccurring disease.  Depending on the timing of treatment and the severity of the illness, recovery may take a few weeks to several months.

How to prevent brucellosis

  • Do not consume milk, cheese, ice cream, or other dairy products while traveling unless you can verify that it is a pasteurized dairy product.
  • Wild pigs may be infected with brucellosis.  Do not handle meat from these animals without wearing rubber gloves.  Be sure to bury remains deeply enough that scavengers such as coyotes cannot retrieve them.
  • Hunters, herdsmen, and those working in animal processing should wear rubber gloves when handling animal tissue, including afterbirths.
  • Afterbirths (placenta) can contain Brucella bacteria.  Wear rubber gloves when assisting an animal birth, and disinfect the area following the birth.  Dispose of the afterbirth, discharges, and fetuses.
  • Immunocompromised persons (cancer patients, HIV-infected individuals, or transplantation patients) should not handle dogs infected with Brucella canis.