Brucellosis is a bacterial disease caused by members of the Brucella
genus that can infect humans but primarily infects livestock. Symptoms of the disease include intermittent fever
, sweating, chills, aches, and mental depression. The disease can become chronic and recur, particularly if untreated.
Also known as undulant fever, Malta fever, Gibraltar fever, Bang's disease, or Mediterranean fever, brucellosis is most likely to occur among those individuals who regularly work with livestock. The disease originated in domestic livestock but was passed on to wild animal species, including the elk and buffalo of the western United States. In humans, brucellosis continues to be spread via unpasteurized milk obtained from infected cows or through contact with the discharges of cattle and goats during miscarriage
. In areas of the world where milk is not pasteurized, for example in Latin America and the Mediterranean, the disease is still contracted by ingesting unpasteurized dairy products. However, in the United States, the widespread pasteurization of milk and nearly complete eradication of the infection from cattle has reduced the number of human cases from 6,500 in 1940 to about 70 in 1994.
Causes and symptoms
The disease is caused by several different species of parasitic bacteria of the genus Brucella. B. abortus is found in cattle and can cause cows to abort their fetuses. B. suis is most often found in hogs and is more deadly when contracted by humans than the organism found in cattle. B. melitensis is found in goats and sheep and causes the most severe illness in humans. B. rangiferi infects reindeer and caribou, and B. canis is found in dogs.
A human contracts the disease by coming into contact with an infected animal and either allowing the bacteria to enter a cut, breathing in the bacteria, or by consuming unpasteurized milk or fresh goat cheese obtained from a contaminated animal. In the United States, the disease is primarily confined to slaughterhouse workers.
Scientists do not agree about whether brucellosis can be transmitted from one person to another, although some people have been infected from a tainted blood transfusion
or bone marrow transplant. Newborn babies have also contracted the illness from their mothers during birth. Currently, it is believed that brucellosis can also be transmitted sexually.
The disease is not usually fatal, but the intermittent fevers (a source of its nickname, "undulant fever") can be exhausting. Symptoms usually appear between five days and a month after exposure and begin with a single bout of high fever accompanied by shivering, aching, and drenching sweats that last for a few days. Other symptoms may include headache
, poor appetite, backache, weakness, and depression. Mental depression can be so severe that the patient may become suicidal.
— A specific protein produced by the immune system in response to a specific foreign protein or particle called an antigen.
— Disease or condition characterized by slow onset over a long period of time.
— An organism living in or on, and obtaining nourishment from, another organism.
— The process of applying heat, usually to milk or cheese, for the purpose of killing, or retarding the development of, pathogenic bacteria.
In rare, untreated cases, the disease can become so severe that it leads to fatal complications, such as pneumonia
or bacterial meningitis
. B. melitensis
can cause miscarriages, especially during the first three months of pregnancy
. The condition can also occur in a chronic form, in which symptoms recur over a period of months or years.
Brucellosis is usually diagnosed by detecting one or more Brucella species in blood or urine samples. The bacteria may be positively identified using biochemical methods or using a technique whereby, if present in the sample, the brucellosis bacteria are made to fluoresce. Brucellosis may also be diagnosed by culturing and isolating the bacteria from one of the above samples. Blood samples will also indicate elevated antibody levels or increased amounts of a protein produced directly in response to infection with brucellosis bacteria.
Prolonged treatment with antibiotics
, including tetracyclines
(with streptomycin), co-trimoxazole, and sulfonamides
, is effective. Bed rest is also imperative. In the chronic form of brucellosis, the symptoms may recur, requiring a second course of treatment.
Early diagnosis and prompt treatment is essential to prevent chronic infection. Untreated, the disease may linger for years, but it is rarely fatal. Relapses may also occur.
There is no human vaccine for brucellosis, but humans can be protected by controlling the disease in livestock. After checking to make sure an animal is not already infected, and destroying those that are, all livestock should be immunized. Butchers and those who work in slaughterhouses should wear protective glasses and clothing, and protect broken skin from infection.
Some experts suggest that a person with the disease refrain from engaging in unprotected sex until free of the disease. The sexual partners of an infected person should also be closely monitored for signs of infection.
Centers for Disease Control and Prevention. 1600 Clifton Rd., NE, Atlanta, GA 30333. (800) 311-3435, (404) 639-3311. http://www.cdc.gov.
"Bacterial Diseases." Healthtouch Online Page. 〈http:www.healthtouch.com〉.
Centers for Disease Control. 〈http://www.cdc.gov/nccdphp/ddt/ddthome.htm〉.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
a generalized infection involving primarily the reticuloendothelial system, marked by remittent fluctuating fever, malaise, and headache. It is caused by various species of Brucella
and is transmitted to humans from domestic animals such as pigs, goats, and cattle, especially through infected milk or contact with the carcass of an infected animal.
The disease is also called undulant fever
because one of the major symptoms in humans is a fever that fluctuates widely at regular intervals. The symptoms in the beginning stages are difficult to notice and include loss of weight and increased irritability. As the illness advances, headaches, chills, diaphoresis, and muscle aches and pains appear. It is possible for these symptoms to persist for years, either intermittently or continuously, although most patients recover completely within 2 to 6 months. Diagnosis is confirmed by blood cultures or serologic agglutination tests.Treatment
consists of rest and supportive care with a prolonged antibiotic regimen. Prevention
is best accomplished by the pasteurization of milk and a program of testing, vaccination, and elimination of infected animals.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Infectious diseases caused by the bacteria Brucella melitensis biovars, characterized by fever, sweating, weakness, orchitis, aches, and pains, and transmitted to humans by direct contact with diseased animals or through ingestion of infected meat, milk, or cheese, and particularly hazardous to veterinarians, farmers, and slaughterhouse workers; although some crossing over by species may occur, Brucella melitensis, Brucella melitensis biovar abortus, Brucella melitensis biovar canis, and Brucella melitensis biovar suis characteristically affect goats, cattle, dogs, and swine, respectively.
Farlex Partner Medical Dictionary © Farlex 2012
Bruce, Sir David, English surgeon, 1855-1931.
- infectious bacteria causing abortions in cattle, sheep, mares; causes undulant fever in man and a wasting disease in chickens. Synonym(s): abortus bacillus
; Bang bacillus
Brucella - a genus of encapsulated, nonmotile bacteria (family Brucellaceae) causing infection of the genital organs, the mammary gland, and the respiratory and intestinal tracts.
brucellosis - an infectious disease caused by Brucella, and transmitted by direct contact with diseased animals or through ingestion of infected meat, milk, or cheese. Synonym(s): febris undulans; Malta fever; Mediterranean fever; undulant fever
Malta, an island in the Mediterranean Sea south of Sicily.
Malta fever - Synonym(s): brucellosis
Medical Eponyms © Farlex 2012