Diphtheria, Tetanus, and Pertussis (DTaP) Diphtheria, pertussis, and tetanus are serious illnesses. A combination vaccine is given to babies and children to provide protection against all three diseases. Measles, Mumps, and Rubella (MMR) The MMR vaccine is given in two doses—at 12 to 15 months and at 4 to 6 years, or at least one month after the first dose. Polio (IPV) The poliovirus destroys the nervous system, causing paralysis. Today, polio is extremely rare in the United States because of the polio vaccine. It's still common in other countries, though, so children still need to be immunized. Haemophilus Influenzae Type b (Hib) Haemophilus influenzae type b is a serious bacterial disease that usually strikes children younger than 5. It is spread from person-to-person by coughing and sneezing. Varicella (Chickenpox) Chickenpox is a very common childhood disease. It is usually mild, but can be serious, especially in young infants and adults. Pneumococcus Pneumococcus bacteria can cause serious illness in children, including pneumonia, infection in the blood, and meningitis. Hepatitis B (HBV) in Children An infant or young child who contracts hepatitis B is at greater risk of staying infected with the virus and of having life-long liver problems, such as scarring of the liver and liver cancer. Childhood Immunizations Your little one will need several immunization shots to help protect her from several childhood diseases, some of which can be deadly. Knowing which shots she needs, when, and what to do in the event of a minor reaction is important. What Every Parent Should Know About Vaccinations Where can you as a parent turn to for the facts about vaccine safety? The first place to go is your child's doctor.