Your child will be exposed to a great number of minor, self limited contagious diseases on a daily basis through family, day care, school, and other social contacts.  These risks can be minimized by simple hygienic measures such as frequent handwashing.  Most illnesses do not represent a danger.  Rarely, however, exposure can occur to serious infectious illnesses such as measles, hepatitis, or spinal meningitis.  There are very specific recommendations for each of these, and your doctor’s office should be contacted.