three-day POLIO Polio, also known as poliomyelitis and infantile paralysis, is an infection of the spinal cord that can, in 1 to 2 percent of cases, lead to paralysis or death. Outbreaks of polio still occur in this country, and infants should receive two or three doses of the Sabin vaccine, which provides protection against all three types of polio. The first dose should be given at two months, with the second and third doses separated by intervals of six weeks to two months. This vaccine is given by mouth, not as an injection. A booster series should be given at the age of oneandahalf to two years, and again at four to six years. Children who were not immunized in infancy should receive a total of three or four doses, depending on their ages. The Sabin vaccine is undoubtedly safe for children. Adults who are not immune and who plan to travel to a country where polio is uncontrolled should also be immunized. In fact, all adults should be immunized against this disease. Some medical authorities believe that the risk of an adult being exposed to polio within the United States is minimal, and therefore adult immunization is unnecessary. However, too many cases of polio have occurred in adults over the age of 30 to make this argument acceptable. Because the Sabin vaccine is a "live" vaccine (meaning that it contains live organisms), it does carry a slight risk of polio for adults. However, the Salk vaccine (a dead vaccine, prepared from inactivated organisms) does not. Adults who are not immune should receive an initial series of Salk vaccine to acquire temporary immunity, followed by a full series of Sabin vaccine for permanent protection. MEASLES, MUMPS, AND RUBELLA The live measlesmumpsrubella (MMR) combination vaccine should be given to children at the age of 15 months. It confers long term (probably lifelong) immunity against all three diseases. Measles. Measles is a contagious viral disease that affects mainly the respiratory system, the eyes, and the skin. It is considered dangerous mainly because its complications can include pneumonia (inflammation of the lungs), encephalitis (inflammation of the brain), and ear infections. Because most children are now vaccinated against it, measles is seldom seen today. The risk of a child contracting encephalitis from the vaccine is less than one in a million, and pneumonia and ear infections are never seen as a consequence of immunization. Mumps. Mumps is a contagious viral disease that causes swelling of the parotid glands, which are the salivary glands beneath the ear. Mumps can be painful and uncomfortable, but seldom has longterm complications. The most serious complication of mumps is encephalitis (inflammation of the brain), which can be followed by hearing loss or deafness. The mumps vaccine, which is included in the MMR vaccine, is harmless to the child and is 95 percent effective in preventing the disease. Rubella. Rubella, or German measles, is a contagious viral disease that produces mild, coldlike symptoms and a shortlived rash. pox