The same general food safety guidelines apply to hot dogs as to all perishable foods: keep hot foods hot and cold foods cold. When you buy hot dogs, refrigerate or freeze them promptly. Never leave hot dogs at room temperature for more than 2 hours or 1 hour if it is 90 degrees or higher.
Although hot dogs are fully cooked, those at higher risk for foodborne illness—including pregnant women, preschoolers, older adults, and anyone with a weakened immune system—should reheat hot dogs until steaming hot because of the risk of listeriosis. Listeria monocytogenes, the bacteria that causes listeriosis, may also be found in other foods like luncheon meat, cold cuts, soft cheese, and unpasteurized milk. Symptoms may include fever, chills, headaches, backache, upset stomach, abdominal pain, and diarrhea. It may also cause miscarriages. Call your health care provider if you have any of these symptoms. If you have Listeriosis, your provider can treat you.
Source: Food Safety and Inspection Service, USDA