Abstract
Brucellosis remains one of the most common zoonotic human infections, over a century after core methods of prevention were first implemented in Malta. Despite successful eradication in animals and humans from some countries, there has been expanded recognition of human brucellosis throughout southeast and east Asia. Infection has re-emerged in zones of conflict and it is a common cause of fever in North and East Africa. In Western Europe and North America, increasing canine infections with B. canis pose an uncertain threat to humans. The protean clinical features of human disease are well described but diagnostic awareness among clinicians is variable, especially outside endemic areas. Differentiation from tuberculosis is critical when deciding on therapy, particularly in resource poor settings. Diagnostic needs include: implementation of standardized serological tests; development of serological tests for organisms such as B. canis; consensus on the role of PCR and interpretation of significance of prolonged PCR positivity after treatment. Reference databases for matrix assisted laser desorption ionization-time of flight mass spectrometry (MAL-DI-TOF MS) and similar diagnostic tools need enhancement to differentiate Brucella spp. from each other and from newly incorporated species such as Brucella (Ochrobactrum) intermedium, which are rarely pathogenic. Therapy requires at least two antimicrobial agents to reduce the risk of clinical relapse, but there have been no well-designed prospective trials for decades to determine: the optimum dose, duration and safety of modern aminoglycosides instead of streptomycin; the role of fluoroquinolones; optimum duration of treatment for focal skeletal disease; the best therapeutic combinations and duration for children. Staff exposure to live organisms is still a problem in human and veterinary diagnostic laboratories. The need for dual therapy regimens for post exposure prophylaxis (PEP) is debatable and could be reduced to a single drug, with simpler post exposure monitoring programmes to improve PEP adherence. If safe vaccines become available, their use is likely to be limited to selected groups. Mortality should not exceed 1% but human morbidity is substantial, yet clinical research is difficult to fund and poses logistic challenges. This mightimprove if human brucellosis was formally recognized as a neglected tropical disease.
