Brucellosis, also known as undulant fever or Malta fever, is a varied illness consisting of fever, debility, headache, marked and persistent sweating, joint pains, and aching of the limbs and back. If the infected person or animal is pregnant, abortion usually results. The causal organisms are small bacteria of the Brucella genus which persist among animals: pigs, sheep, cattle, goats and horses being the most important in temperate climates. The infection reaches man by contact with animal fomites, e.g. blood, placenta, urine; inhalation of bacteria from the same sources; or drinking or eating Brucella -contaminated milk, cream or cheese. The causal organisms are Brucella abortus, B. suis, and B. melitensis.
The patient is investigated by culturing the bacteria from urine, blood, or other specimens; by serological tests aimed at detecting antibodies to the presence of the organism: and occasionally by examination of tissues such as an aborted foetus or placenta. As, however, the disease may occur in a subacute or milder form, it may go unrecognised or be passed off as a relatively unimportant flu-like illness, which accounts for serious underreporting in many parts of the world. People especially at risk are veterinary surgeons, meat-packers and abattoir-workers, farm-workers, others involved in dealing with animals, and laboratory workers. Some countries, for example Indonesia, have no indigenous brucellosis. Others, such as the United Kingdom, USA, Mediterranean countries, Russia, and South America, have persistent reports of moderate incidences.
Various brucellosis eradication schemes are now under way. In Britain, compulsory blood testing began in some areas on 1 November 1971, when over 3700 herds were found brucellosis-free. About 90 per cent of the animals under study were found free of the disease after three blood tests. Total eradication is anticipated in the early 1980s. Until then, control depends upon pasteurisation of dairy produce, disinfection of animal products, elimination of transmission risks from infected animals, and the safe handling of known contaminated sources by scientists and veterinary workers. Tetracyclines, alone or in combination with other antibiotics, are used in treatment, but relapses occur.