Some persons at particularly high risk should take more precautions.
Weakened Immune Systems
Pregnant women, the elderly, and those weakened immune systems are at higher risk for severe infections such as Listeria and should be particularly careful not to consume undercooked animal products. They should avoid soft French style cheeses, pates, uncooked hot dogs, and sliced deli meats, which have been sources of Listeria infections. Persons at high risk should also avoid alfalfa sprouts and unpasteurized juices. A bottle-fed infant is at higher risk for severe infections with Salmonella or other bacteria that can grow in a bottle of warm formula if it is left at room temperature for many hours. Particular care is needed to be sure the baby’s bottle is cleaned and disinfected and that leftover milk formula or juice is not held in the bottle for many hours.
Persons with liver disease are susceptible to infections with a rare but dangerous microbe called Vibrio vulnificus, found in oysters. They should avoid eating raw oysters.