A: These shots protect your baby from nine diseases: measles, mumps, rubella (German measles), diphtheria, tetanus, pertussis (whooping cough), polio, Haemophilus influenzae type b (Hib) and hepatitis B.

Q: Are these diseases very serious?

A: Today, we might not think of these diseases as being very serious because, thanks to vaccines, we don't see them as often as we used to. But they can still be deadly. Measles used to kill hundreds - sometimes thousands - of people a year. In the 1920's, more than 10,000 people a year died from diphtheria. And in the 1940's and '50's, tens of thousands of children were crippled and killed by polio. Even today, these diseases can lead to pneumonia, choking, brain damage, heart problems and blindness in children who are not protected. And they still kill children every year.

Q: Are shots safe?

A: Yes, very safe. But like any medicine they can occasionally cause reactions. Usually these are mild, like a sore arm or a slight fever. Serious reactions are rare, but they can happen. Your doctor or nurse will discuss these issues with you before giving the shots. The important thing to remember is that children are in much more danger from the diseases than from the shots.

Q: How many shots does my child need, and when?

A: Your child should get his or her first shots at 2 months of age (or in some cases before he leaves the hospital after birth). You will have to go back for more shots four or five times before the child starts school. Your doctor or nurse will tell you when to come back. Remember, each of these visits is important! Your child needs several doses of each vaccine to be completely protected.

Q: Isn't getting all these shots expensive?

A: It doesn't have to be. If you take your child to a public health clinic, you might have to pay a small charge for the nurse to give the shots, but the shots themselves are free. Clinics that are supplied the vaccines from the government are forbidden by law from withholding the vaccinations because you can't pay.

Q: Why should I get my child immunized?

A: By getting your child immunized, you will be fighting disease in two ways. First, you will be protecting your own child. And second, since healthy children don't spread disease, you will be protecting others as well.

Q: How do vaccines work?

A: When you get an infection, your body reacts by producing substances called antibodies. These antibodies fight the disease and help you to get over the illness. They usually stay in your system, even after the disease has gone, and protect you from getting the same disease again. This is called immunity.

Newborn babies are immune to many diseases because they have antibodies they have gotten from their mothers. But this immunity doesn't last. It wears off during the first year of life.

Fortunately, we can keep children immune to many diseases, even after they lose their mothers' antibodies. We do this by vaccinating them against those diseases. The germs that cause disease are made into vaccines. These vaccines can be given to children as shots or as drops to be swallowed. Vaccines fool the body into thinking it is under attack by disease, and the body reacts by producing antibodies. These antibodies stay in the body. Then, if the child is exposed to the actual disease, he or she is protected.

Q: What will happen if my child doesn't get these shots?

A: Three things can happen.

1. If your child is never exposed to any of these diseases, nothing will happen.
2. If your child is exposed to any of these diseases, there is a good chance he or she will get the disease. What happens then depends on the child and the disease. At the least, the child could get a mild rash and have to stay inside for a few days. At the worst, the child could die.
3. If your child gets one of these diseases, he or she could also spread it to other children who are not protected. If there are enough of these children in your community, it could lead to an epidemic, with many children getting sick.

A: It's hard to say. Some of these diseases are very rare in the United States today, so the chances of exposure are small. Others are more common.

Q: What if my child didn't get her shots when she was supposed to, or has gotten behind schedule?

A: If you have children who did not begin their immunizations at 2 months of age, or who have had only some of their shots, they can still be fully immunized. It is never too late to start getting immunizations. If your children have had some of shots and then gotten behind schedule, they don't have to start over. The shots already given will count. Just continue the schedule where they left off. If you have children who were not immunized when they were infants, contact your doctor or the health department clinic. They will tell you when to bring the children in for their shots.