Molecular Diagnosis of Acute and Chronic Brucellosis in Humans

Human brucellosis is a zoonosis distributed in many countries around the world. It represents an important public health problem in areas where Brucella infection is primarily enzootic in cattle, sheep, goat, and swine populations. More than 500,000 new human cases are reported annually worldwide, whereas the number of undetected cases is believed to be considerably higher. Both microbiological and serological methods are commonly used for diagnosis and characterization of Brucella infections. However, DNA-based assays such as conventional PCR, real-time PCR, MLST, as well as MLVA have provided better sensitivity when compared to bacteriological tests and much more specificity than the traditional serological methods. In addition, PCR assays allow the fast detection of Brucella infections and detection of relapse and facilitate the post-treatment follow-up of the patients. The improvement and optimization of molecular techniques along with their accessibility to most clinical laboratories allow the rapid diagnosis of the disease and better control of occupational risks for laboratory personnel while handling live Brucella spp. Therefore, PCR-based methods represent applicable and very efficient methods for the diagnosis of acute brucellosis at the earlier time of disease, exploring predictive biomarkers for the post-treatment control as well as for monitoring the course of the disease evolution for the early recognition of relapses.