| Brucellosis, also called undulant fever, or Malta fever, | | | | 200 cases occur in the U.S. each year. People working |
| in humans is a highly contagious zoonosis (infectious | | | | in jobs requiring frequent contact with animals or |
| disease transmitted from animals to humans) caused | | | | meat -- such as slaughterhouse workers, farmers, |
| by bacteria of the genus Brucella. Brucella spp. are | | | | and veterinarians -- are at high risk. |
| small, gram-negative, non-motile, non-spore-forming | | | | Symptoms |
| rods. Brucella spp. are facultative intracellular parasites | | | | Symptoms of brucellosis include intermittent or |
| causing chronic disease, which usually persists for life. | | | | irregular fever of variable duration, headache, |
| Brucellosis is a bacterial disease of both humans and | | | | weakness, profuse sweating, chills, weight loss and |
| animals recognized since the 19th century. | | | | generalized aching. Brucellosis can also cause |
| Brucella are rod-shaped bacteria that lack a capsule | | | | long-lasting or chronic symptoms such as recurrent |
| around their cell membranes. Unlike most bacteria, | | | | fevers, joint pain and fatigue. |
| Brucella cause infection by actually entering host cells. | | | | The symptoms are like those associated with many |
| As the bacteria cross the host cell membrane, they | | | | other febrile diseases, but with emphasis on muscular |
| are engulfed by host cell vacuoles called phagosomes. | | | | pain and sweating. The duration of the disease can |
| The presence of Brucella within host cell phagosomes | | | | vary from a few weeks to many months or even |
| initiates a characteristic immune response, in which | | | | years. In first stage of the disease, septicaemia |
| infected cells begin to stick together and form | | | | occurs and leads to the classic triad of undulant |
| aggregations called granulomas. | | | | fevers, sweating (often with characteristic smell, |
| Brucellosis is an infectious disease caused by the | | | | likened to wet hay) and migratory arthralgia and |
| bacteria of the genus Brucella. These bacteria are | | | | myalgia. In blood tests, is characteristic the leukopenia |
| primarily passed among animals, and they cause | | | | and anaemia, some elevation of AST and ALT and |
| disease in many different vertebrates. Various | | | | positivity of classic Bengal Rose and Huddleson |
| Brucella species affect sheep, goats, cattle, deer, elk, | | | | reactions |
| pigs, dogs, and several other animals. Humans | | | | This intermittent fever usually lasts 1 to 5 weeks, |
| become infected by coming in contact with animals | | | | after which symptoms usually subside or disappear |
| or animal products that are contaminated with these | | | | for two days to two weeks. Then the fever recurs. |
| bacteria. In humans brucellosis can cause a range of | | | | In some patients, this fever recurs only once. In |
| symptoms that are similar to the flu and may include | | | | others, the disease becomes chronic, and the fever |
| fever, sweats, headaches, back pains, and physical | | | | recurs, subsides, and then recurs again repeatedly |
| weakness. | | | | over months or years. |
| Causes | | | | Diagnosis |
| Brucella can infect cattle, goats, camels, dogs, and | | | | Brucellosis is diagnosed in a laboratory by finding |
| pigs. The bacteria can spread to humans if you come | | | | Brucella organisms in samples of blood or bone |
| in contact with infected meat or the placenta of | | | | marrow. Also, blood tests can be done to detect |
| infected animals, or if you eat or drink unpasteurized | | | | antibodies against the bacteria. If this method is used, |
| milk or cheese. Brucellosis is rare in the United States | | | | two blood samples should be collected 2 weeks |
| (except in the western states). Approximately 100 - | | | | apart. |