Brucellosis

Brucellosis, also known as undulant fever, Malta fever, or Mediterranean fever, is a zoonotic infectious disease caused by bacteria of the genus Brucella. The most common species affecting humans include Brucella melitensis (from goats and sheep), Brucella abortus (from cattle), Brucella suis (from pigs), and Brucella canis (from dogs). Humans typically acquire the infection through consumption of unpasteurized dairy products, direct contact with infected animals or their secretions, or inhalation of contaminated aerosols. The disease is considered rare in developed countries but remains endemic in parts of the Mediterranean, Middle East, Central Asia, and Latin America. Brucellosis is a systemic infection that can affect virtually any organ system. The bacteria invade the reticuloendothelial system, affecting the liver, spleen, bone marrow, and lymph nodes. Key clinical features include undulating (wave-like) fever, profuse sweating (often with a characteristic odor), fatigue, malaise, joint and muscle pain, headache, and weight loss. Hepatosplenomegaly (enlargement of the liver and spleen) is common. Complications can involve the musculoskeletal system (sacroiliitis, spondylitis, arthritis), cardiovascular system (endocarditis, which is the leading cause of brucellosis-related mortality), central nervous system (neurobrucellosis with meningitis or encephalitis), and genitourinary system (epididymo-orchitis). The disease can follow an acute, subacute, or chronic course, and relapse is common if inadequately treated. Treatment of brucellosis requires prolonged combination antibiotic therapy. The World Health Organization recommends doxycycline combined with streptomycin or rifampicin for a minimum of six weeks. For complicated cases such as neurobrucellosis or endocarditis, treatment duration is extended and may include additional agents such as trimethoprim-sulfamethoxazole or ceftriaxone. Early diagnosis and appropriate treatment generally lead to a good prognosis, though chronic forms and relapses can occur. There is no widely available human vaccine, and prevention relies on animal vaccination programs, pasteurization of dairy products, and occupational safety measures for those working with livestock.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Brucellosis