It’s the contaminated dry dog food that was the source of an outbreak of Salmonella infections affecting people in 19 states, asserted the public health officials report published in the Morbidity and Mortality Weekly Report, a weekly epidemiological digest for the United States published by the Centers for Disease Control and Prevention.

CDC officials reported that Salmonella comes from undercooked meats and eggs; dry dog food may be an under-recognized source of illness in humans, but they are unsure how the bacteria got into the dog food.

Dr. Casey Barton Behravesh, a CDC epidemiologist and co-authored of the report, said, “They are a number of possible ways that that could happen. That’s something we are still trying to figure out.”

Dr. A. Ferraro, at the Pennsylvania Department of Health, and colleagues reported that a large number of cases were detected in Pennsylvania (29 cases), New York (9 cases), and Ohio (7 cases); roughly 40 percent of infected individuals were infants.

Dr. Barton Behravesh advised, "The most important thing is to wash your hands right after you handle any dry dog food, any other pet food, pet treats, even supplements or vitamins. In addition, keep infants and other young children away from pet food, because kids tend to want to see what their dogs are eating and grab at the pet food and play with it or even put it in their mouth."