An illness caused by infection with bacteria and spread from animals to people, mostly through raw dairy products.

Brucellosis is caused by a type of bacteria carried by many animals. Dairy products that aren't treated to remove bacteria are a common way people get brucellosis. Direct contact with an infected animal also can spread the bacteria. Untreated brucellosis can lead to other medical issues throughout the body.

Brucellosis symptoms may go away and come back over weeks or months. Chills, not wanting to eat, heavy sweating and tiredness are some brucellosis symptoms. Others are a fever that goes up fast or lasts, muscle aches, or unusual weakness.

Medicines that target bacteria, called antibiotics, treat brucellosis. The disease may return after treatment. Long-term infections are called chronic brucellosis.