A total of 25 people have been killed in 12 U.S. states in a listeria outbreak traced to Colorado cantaloupes, the U.S. Centers for Disease Control and Prevention ( CDC) said Wednesday. The number of people sickened by the tainted cantaloupes has reached 123 in 26 states, with Pennsylvania reporting its first case. One of the ill patients, a pregnant woman, suffered a miscarriage, the CDC said in a telebriefing. The listeria outbreak has been the most deadly one since 1998, according to the CDC. Listeria is a common bacterium that typically causes mild illness in healthy people, but can cause severe illness in older people and those with compromised immune systems. It also can cause miscarriages and stillbirths in pregnant women and severe infections in new babies. The CDC estimates that about 48 million people in the U.S. each year get sick from tainted food, with about 128,000 hospitalized and 3,000 deaths.