Alice Catherine Evans service worker was protected by law. Alice became interested in the disease brucellosis and its relationship to fresh, unpasteurized milk. Alice's investigation focused on the organism "Bacillus abortus", known to cause miscarriages in animals. Alice learned that the microbe thrived in infected cows as well as animals that appeared healthy. The reports hypothesized that since the bacteria was found in cow's milk, a threat to human health was likely. Evans decided to investigate this; she wondered whether the disease in cows could be the cause of undulant fever in humans. She reported her findings to the Society of American Bacteriologists
Brucellosis (goats and sheep), "B. ovis" (sheep), and "B. suis" (caribou and pigs). "Brucella" species have also been isolated from several marine mammal species (cetaceans and pinnipeds). "B. abortus" is the principal cause of brucellosis in cattle. The bacteria are shed from an infected animal at or around the time of calving or abortion. Once exposed, the likelihood of an animal becoming infected is variable, depending on age, pregnancy status, and other intrinsic factors of the animal, as well as the number of bacteria to which the animal was exposed. The most common clinical signs of cattle infected with "B. abortus"