Salmonella infection (salmonellosis) is an illness that affects your intestines. It is caused by Salmonella bacteria. You can be infected by eating or drinking contaminated food or water. Beef, pork, chicken, eggs, and unpasteurized milk are more likely to carry this bacteria than other foods. But vegetables may also be contaminated. Salmonella most often passes through food that hasn't been cooked well enough. Or food that contains raw meat or eggs. You can also be infected by contact with the stool (feces) of infected animals. Or by food that an infected food handler contaminates.