Brucellosis: An updated review of the disease

Abstract

Brucellosis is a chronic infectious disease caused by small, non-motile, non-sporing, gram-negative, facultative
intracellular coccobaccilli of the genus Brucella. This disease may affect a range of different mammals including cattle,
buffalo, sheep, goat, swine, rodents, man and marine mammals. It is a major bacterial zoonosis of global public health
importance. In most of the animal species, the disease primarily affects the reproductive system with concomitant loss
in productivity. Both humoral and cellular immune responses are involved in Brucella infection. Clinical signs of
Brucella infection are non-pathognomonic and thus diagnosis of the disease is mainly dependent on laboratory tests.
The conventional tests, viz. Rose Bengal plate agglutination test (RBPT), serum tube agglutination test (SAT) and
complement fixation test (CFT) are commonly used. Isolation is still the gold standard. Other commonly used tests are
enzyme linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), native hapten (NH) gel precipitation
tests, brucellin skin test and fluorescence polarization assay (FPA).