Brucellosis is a disease caused by bacteria called Brucella. It is spread from animals to humans. The bacteria multiply in the reproductive organs and mammary glands of infected animals. The disease is rare in Singapore but common in less developed countries.

Anyone can get brucellosis if they are exposed to Brucella. Occupations at highest risk are veterinarians and those who slaughter animals for a living. Persons who consume unpasteurised milk and cheeses made with raw milk can also get infected.

There is no effective way to detect infected animals by their appearance. The most obvious signs in pregnant animals are abortion or birth of weak calves. Milk production may also be reduced. Even though their calves may appear healthy, infected cows continue to harbour and discharge infectious organisms and should be regarded as dangerous sources of the disease. Occasionally, the joints may be enlarged and arthritic.

Brucellosis is spread to humans through contact with blood, body tissues, or body fluids of infected animals. The most common method is consumption of unpasteurised milk and dairy products. Human infections may occur through breaks in the skin when handling infected animal tissue. Human breast milk can also be a source of transmission of the disease.

Milk and dairy products from domestic animals such as cattle, sheep, goats and camels can carry the disease.

In humans, the symptoms of brucellosis include fever, night sweats, extreme fatigue, loss of appetite, weight loss, headache, and joint pain. The onset may be acute or insidious (i.e. subtle) and the fever may be continuous, intermittent, or irregular. The disease may last for several days, months, or occasionally up to a year or more if not adequately treated. You should consult your doctor for advice if you have the above symptoms.

The incubation period is highly variable and difficult to ascertain; usually 5 to 60 days, occasionally up to 6 months. In other words, it is possible for an individual to come down with brucellosis up to 6 months after he has returned from a high-risk area.

Diagnosing the disease requires blood tests. Several different methods are available to diagnose the disease. Exposure history is very important in the diagnosis of suspected cases.

Treatment usually requires long-term antibiotic therapy. Some regimens may include two different antibiotics for six weeks or more. Relapses can occur as the organism can still persist in the body if there is inadequate treatment.

Human to human transmission is very unlikely, but possible through exchange of body fluids such as blood and breast milk.

Brucellosis may produce a mild disease in humans or cause severe temporary or permanent damage if left untreated. Complications include damage to bones and joints, the genitourinary tract, meningitis, and endocarditis (an infection of the heart valves).

Food-borne transmission of brucellosis has become the most common means of exposure to the disease. While brucellosis is rare in Singapore, persons travelling to Latin America, Eastern Europe, Central Asia, Africa, India, the Mediterranean and the Middle East are at increased risk of exposure.

Travellers should only consume pasteurised dairy products while overseas. Do not buy dairy products from unlicensed retailers, street vendors, or other questionable sources. Dairy products should be avoided unless you can be absolutely certain that they were made from pasteurised milk. It is also unsafe to consume uncooked meat and organs of animals.

Travellers with history of exposure to unpasteurised dairy products or body fluids of animals in endemic countries should look out for symptoms of the disease and seek early medical attention if necessary.