Undulant fever, malta fever, abortus fever.

A zoonotic bacterial infection of acute onset. Common as an occupational disease among people working with infected livestock or associated fresh animal products, for example butchers, farmers, abattoir workers, and vendors of contaminated roasted meat (muchomo). Incubation is 2-4 weeks on average, but it can be from 1 to 8 weeks.

  • Intermittent (fluctuating) fever
  • Aches and pains
  • Orchitis (inflammation of the testes)
  • Vertebrae osteomyelitis (uncommon but characteristic)

  • Typhoid fever, malaria, tuberculosis
  • Trypanosomiasis (sleeping sickness)
  • Other causes of prolonged fever

  • Blood: complement fixation test or agglutination test (where possible). The interpretation of serological tests can be difficult, particularly in endemic areas where a high proportion of the population has antibodies against brucellosis. Positive serological test results can persist long after recovery in treated individuals so results have to be interpreted on the basis of the clinical picture
  • Isolation of the infectious agent from blood, bone marrow, or other tissues by culture


Brucella abortus (cattle)

Brucella canis (dog)

Brucella melitensis (goats and sheep)

Brucella suis (pigs)