Brucellosis: Correct Statement
Statement A is correct: Transmission to humans occurs through contact with animals or their products. This is the fundamental epidemiological characteristic of brucellosis as a zoonotic disease 1, 2.
Why Statement A is Correct
Brucellosis is transmitted to humans primarily through:
- Consumption of contaminated animal products (unpasteurized dairy, undercooked meat) 1
- Direct contact with infected animals (livestock, wildlife) 1
- Occupational exposure in healthcare workers, veterinarians, and abattoir personnel 2
This zoonotic transmission pattern is well-established across all evidence sources and represents the cornerstone of brucellosis epidemiology 3, 4.
Why the Other Statements are Incorrect
Statement B (Hepatosplenomegaly) - FALSE
Brucellosis does cause hepatosplenomegaly. Recent case reports document acute liver injury as a complication 5, and hepatic involvement with elevated aminotransferases is a recognized manifestation of the disease.
Statement C (Lung as Most Affected Organ) - FALSE
The lung is not the most frequently affected organ. Brucellosis is a systemic infection with:
- Non-specific systemic symptoms (fever, fatigue, sweats)
- Musculoskeletal involvement (most common focal complication)
- Hepatosplenic involvement
- Hematologic complications (thrombocytopenia, DIC in severe cases) 5
Statement D (Vancomycin Monotherapy) - FALSE
This is completely incorrect. The treatment of choice requires:
- Doxycycline 100 mg twice daily for 6 weeks PLUS either:
- Streptomycin 1g daily for 2-3 weeks, OR
- Rifampicin 600-900 mg daily for 6 weeks 6
- Gentamicin may substitute for streptomycin 6
- Combination therapy is mandatory to prevent relapse (5-15% with proper treatment) 6
Vancomycin has no role in brucellosis treatment and monotherapy is never appropriate.
Statement E (Diagnosis Solely by Culture) - FALSE
Diagnosis requires multiple complementary methods 7, 5:
- Blood cultures (slow, modest sensitivity, considered reference standard)
- Serological assays (primary diagnostic tool in routine practice) 7
- Molecular methods including next-generation sequencing 7, 5
- Clinical correlation is essential due to non-specific symptoms 1
Culture alone is insufficient given its limitations in sensitivity and the slow growth characteristics of Brucella species 7.