Brucellosis is an infectious disease caused by the Brucella bacteria. Brucella species of major concern are B. abortus, primarily affecting cattle, B. melitensis, primarily affecting sheep and goats and B. suis, primarily affecting pigs. All these Brucella species are non-host-specific and may be transmitted to other animal species or humans under appropriate conditions.
Symptoms of a Brucella infection are often decreased milk production, weight loss, abortions, infertility and lameness. Brucella uptake occurs orally, via skin wounds or mucus membranes. Brucella bacteria are mainly excreted with aborted placenta and fetuses, and with semen and milk. Occasionally, animals may recover after a period of time. More commonly, however, the symptoms disappear but the disease prevails. Such asymptomatic animals are dangerous sources of infection.
Brucellosis is commonly transmitted to susceptible animals by direct contact with infected animals or in an environment that has been contaminated with discharges from infected animals. Brucellosis is thus a herd or flock problem.
Brucellosis is a notifiable disease, and any occurrence of it has to be reported to the local health authority. Depending on the species and the infection rate, different eradication programs are effective. Where incidence rates are high, vaccination programs are necessary to lower the infection rate. Once this has been achieved, surveillance programs linked to slaughter of infected animals are introduced. These programs lead to 'Brucellosis-Free' and 'Officially Brucellosis-Free' status for specified regions or whole countries. In Europe, surveillance is regulated in the EU directive 2003/99/EC on Monitoring of Zoonoses.
Human health risk
Raw milk and unpasteurized cheeses represent the most important sources of human infection.
Farmers and veterinary staff run an increased risk of infection due to direct exposure to aborted infected materials. In humans the disease is not usually fatal, but if untreated it can last for many years. The incubation period is usually one to three weeks but can sometimes be as long as several months. Patients show unspecific symptoms such as undulating fever, chills, malaises and headache.
Brucellosis is a major public and animal health problem in many regions of the world. Although it rarely kills infected animals, considering the economic damage the disease can cause, Brucellosis is one of the most serious livestock diseases worldwide. This zoonosis has been or is close to being eradicated from a number of countries, but it is still prevalent in the Mediterranean region, Africa, Asia and South America.
The PrioCHECK® Brucella Ab is an indirect ELISA that effectively detects antibodies against Brucella abortus and Brucella melitensis in blood and milk samples of cattle, sheep and goats. The test kit is successfully used for surveillance and monitoring programs and for the diagnosis of individual animals or herds.