Brucellosis is a disease caused by a group of bacteria from the genus Brucella. These bacteria can infect both humans and animals. Brucellosis is often spread when people eat contaminated food, which can include raw meat and unpasteurized milk. The bacteria can also be spread through the air or contact with an open wound.
According to the Centers for Disease Control and Prevention, up to 140 cases of brucellosis are reported annually in the United States. People who work with animals and raw meat (e.g. butchers) have the highest chance of getting brucellosis.
While brucellosis is rare in the United States, it can be serious. You should talk to your doctor if you think you may have brucellosis. Antibiotics can usually treat it. However, some people get this disease repeatedly over the years. Medicine will not necessarily banish it forever.
To lower your risk of getting brucellosis, avoid eating raw meat and unpasteurized dairy products. You should also be sure to wear protective clothing when working with animals or animal tissues.
Causes and Risk
A variety of animals can contract brucellosis, including goats, cattle, and dogs. Humans can then contract the disease from infected animals. The bacteria can be transmitted through ingestion (eating), inhalation (breathing), or contact with an open wound. This is why you have a higher chance of getting brucellosis if you spend a lot of time around animals. The risk is particularly high for people who come in contact with animal urine, blood, or tissue. Animal placenta may also be infected with Brucella bacteria. You may be exposed to the bacteria if you help an animal give birth. Fortunately, brucellosis is rarely spread through casual contact with pets.
People who eat or drink raw animal products are also at higher risk of contracting brucellosis. Unpasteurized milk and cheese, as well as raw meat, can carry Brucella bacteria. Your chances of getting brucellosis are higher if you eat raw dairy or meat products from areas of the world where the disease is more common, such as Asia, Africa, and many parts of Europe.
Fortunately, brucellosis is rarely spread from one human to another. However, it can be spread through breastfeeding or sexual contact. Infection is rare without contact with blood or tissue.
The symptoms of brucellosis in humans are similar to having the flu. The symptoms may include:
- appetite loss
- back pain
- pain in the abdomen
- pain in the joints
- fever that comes and goes
- weight loss
Your doctor may test you for brucellosis if you have unexplained flu-like symptoms. Testing may include:
- blood culture
- urine culture
- bone marrow culture
- cerebrospinal fluid testing
- testing for antibodies to brucellosis
Tell your doctor if you have flu-like symptoms and have been exposed to animals that might have brucellosis. Exposure doesn’t need to be recent. You could have brucellosis even if your contact with animals occurred months ago. If you get this disease, it can take anywhere from one week to two months for symptoms to appear.
Brucellosis is usually treated with antibiotics. Your doctor may prescribe both rifampin and doxycycline. You will need to take these medicines for at least six weeks.
Antibiotics will not always eliminate the bacteria that cause brucellosis. Your doctor may have to prescribe several drugs before the disease is fully treated. In some cases, the bacteria may remain despite treatment.
If treatment isn’t successful, brucellosis can cause complications. These may include:
- encephalitis (inflammation of the brain)
- lesions on the bones and joints
- endocarditis (infection of the heart’s inner lining)
- meningitis (inflammation of the membranes around your brain)
Some of these complications can be lethal. Fortunately, death from brucellosis is rare. The mortality rate for brucellosis is as low as 2 percent. Most people with brucellosis are expected to survive the disease, especially if they don’t have complications.
Brucellosis is preventable. To lower your chances of getting it, you are encouraged to:
- Avoid consuming raw meat or unpasteurized milk, cheese, and ice cream.
- Wear gloves and protective glasses when handling animals or animal tissues.
- Cover any open wounds on your skin when coming in contact with animal blood.
- Wear protective clothing and gloves when helping animals give birth.
There is a brucellosis vaccine for animals. If you work with domestic animals, you should consider vaccinating them for brucellosis. Unfortunately, there is no vaccine for brucellosis in humans. That’s why it’s important to take other steps to protect yourself from the bacteria.