Final answer:
There are vaccines available to prevent brucellosis in animals, which has helped reduce the incidence of the disease. However, there is no widely used vaccine for brucellosis in humans, and treatment typically involves a course of specific antibiotics.
Step-by-step explanation:
Humans can contract brucellosis, also known as undulant fever, through consuming contaminated milk from infected cows or contact with animals. In response to the brucellosis problem, there are indeed vaccines available for animals, which significantly reduce the incidence of the disease in livestock, and by extension, in humans. However, there is no widely used or reliable human vaccine for brucellosis, and the statement referencing a vaccine against Hansen's disease (leprosy) pertains to a different condition caused by a different type of bacterium. Instead, human brucellosis is treated with antibiotics like doxycycline or ciprofloxacin in combination with rifampin.