Brucella

It causes brucellosis which is a zoonoses i.e. infection is acquired from animals. Brucella are Gram negative coccobacilli, non motile and non capsulated. The important species B.abortus, B.melitensis and B.suis. Brucellosis is also called Malta fever, undulant fever or Meditteranean fever. Persons in close contact with animals like farmers, veterinarians etc are at risk. Contaminated food like unpasteurized dairy products are a common source of infection.

It typically presents as PUO (pyrexia of unknown origin) with undulating fever (temperature climbs up and then comes down and the cycle repeats itself) , joint pain, osteomyelitis, lymphadenopathy and sometimes hepatosplenomegaly. For diagnosis either blood, bone marrow, urine or lymph node biopsy samples can be collected. It is isolated faster on special media such as trypticase soy agar, serum dextrose agar, Castaneda’s medium, BACTEC blood culture etc incubated under 10% CO2. ELISA, complement fixation tests and agglutination tests can be used to detect antibodies. Milk ring test is used for detection of animal brucellosis.