Brucellosis Technical Information

Clinical Features

Extremely variable. In the acute form (<8 weeks from illness onset), symptomatic, nonspecific and "flu-like," including fever, sweats, malaise, anorexia, headache, myalgia, and back pain. In the undulant form (<1 year from illness onset), symptoms include undulant fevers, arthritis, and orchiepididymitis in males. Neurologic symptoms may occur acutely in up to 5% of cases. In the chronic form (>1 year from onset), symptoms may include chronic fatigue syndrome-like, depressive episodes, and arthritis.

Etiologic Agent

Brucella species, usually B. abortus (cattle), B. melitensis, B.ovis (sheep, and goats), B. suis (pigs), and rarely B. canis (dogs).

Incidence

In the United States, < 0.5 cases per 100,000 population. Most cases are reported from California, Florida, Texas, and Virginia.

Sequelae

Extremely variable, including granulomatous hepatitis, peripheral arthritis, spondylitis, anemia, leukopenia, thrombocytopenia, meningitis, uveitis, optic neuritis, papilledema, and endocarditis.

Transmission

Zoonotic. Commonly transmitted through abrasions of the skin from handling infected mammals. In the United States, occurs more frequently by ingesting contaminated milk and dairy products. Highly infectious in the laboratory via aerosolization; cultures are considered to warrant biosafety level-3 precautions..

Risk Groups

Abattoir workers, meat inspectors, animal handlers, veterinarians, and laboratorians.

Surveillance

Brucellosis is a nationally notifiable disease and reportable to the local health authority. Trends For previous 10 years, approximately 100 cases per year have been reported.Challenges Elimination of domestic and feral animal reservoirs. Develop a serologic test to detect infection by a recently introduced new live B. abortus vaccine (RB-51).

Opportunities

Identify, transfer to CDC laboratories, test, and improve as needed, rapid diagnostic technologies developed for identification of Brucella spp. for bioterrorism preparedness.