The manual is intended to provide people responsible for the well-being of persons with developmental disabilities with practical information on the prevention of infectious diseases. Diseases are listed alphabetically by most common name. Diseases are also listed by the system or body part it generally affects. Definitions of 26 terms used in the descriptions are given. Among the 44 diseases described are: AIDS (Acquired Immune Deficiency Syndrome), bronchitis, conjunctivitis, ear infection, flu, food poisoning, gastroenteritis, gonorrhea, hepatitis A and B, impetigo, laryngitis, measles, mononucleosis, mumps, pneumonia, ringworm, rubella, scabies, shigella, syphillis, vaginitis, and venereal warts. Under each disease named, answers are provided to the following questions: how soon after exposure to this disease will symptoms appear?, when and for how long is a person contagious?, how is it spread?, what are the symptoms?, how can it be diagnosed?, what is the treatment?, are there any complications?, how common is the disease?, are there any groups of people who are at higher risk?, how can it be prevented?, and are there special considerations for a person with developmental disabilities? Also provided are a listing of state public health departments and a listing of 17 references. (DB)