Immunization

What are immunizations?

Immunizations, also called vaccinations, are given to protect from diseases. Each vaccine contains small amounts of a weakened disease organism or its products, which usually are given by injection. Your immune system develops antibodies to fight the disease, which then recognize and attack the organisms if you are exposed to them in the future. Sometimes an immunization does not completely prevent the disease, but it will significantly reduce its severity. Some immunizations are given only once, while others require several treatments over a period of time.

Why get immunized?

There are several reasons to keep children’s’ immunizations current:

• Being immunized protects you. Diseases still exist and can infect anyone who has not been vaccinated.
• Being immunized protects those around you. A small number of people cannot be immunized because they have other health problems, such as severe allergies. This leaves them susceptible to diseases. Others are not protected from diseases because they do not develop immunity after having vaccinations. If most people are immunized, it reduces the chance of these nonimmune people contracting the disease.
• Immunizations cost very little-much less than treating the illnesses they prevent. The risks are low. Reactions to immunizations are usually mild and don’t last long.
• Immunizations reduce the risk of epidemics.

What reactions may result from being immunized?

Minor side effects

Side effects from vaccines are generally minor, if they occur at all. They may include:

• Redness, mild swelling, or soreness where the shot was given.
• Slight fever.
• Drowsiness, irritability, and poor appetite in some babies.
• A mild rash 7 to 14 days after chickenpox or MMR immunization.
• Temporary joint pain after the MMR vaccine.

Severe side effects

More serious side effects occur very rarely. The risk of a serious complication from a disease is far greater than the risk from a vaccine.

Research is currently under way to better understand which reactions may be caused by vaccines and how to reduce even further the already low risk of complications.

Severe reactions to immunizations, such as a very high fever or difficulty breathing, are rare. If you or your child has an unusual reaction, notify your health professional.

How effective are immunizations at preventing disease?

Although no vaccine is 100% effective, most routine childhood immunizations are effective for 85% to 95% of the children who receive them.

Some people do not develop complete immunity even when they have had the vaccine. If these people are exposed to the disease, they are likely to become infected. However, symptoms are usually milder as a result of having had the vaccine.

The Center for Disease Control (CDC) recommends all children receive vaccines according to the recommended immunization schedule to protect them from 14 diseases by age two.

CDC FAQs

Q: Are vaccines safe?

A: Yes. Vaccines are very safe. The United States’ long-standing vaccine safety system ensures that vaccines are as safe as possible. Currently, the United States has the safest vaccine supply in its history. Millions of children safely receive vaccines each year. The most common side effects are typically very mild, such as pain or swelling at the injection site.

Q: What are the risks and benefits of vaccines?

A: Vaccines can prevent infectious diseases that once killed or harmed many infants, children, and adults. Without vaccines, your child is at risk for getting seriously ill and suffering pain, disability, and even death from diseases like measles and whooping cough. The main risks associated with getting vaccines are side effects, which are almost always mild (redness and swelling at the injection site) and go away within a few days. Serious side effects after vaccination, such as a severe allergic reaction, are very rare and doctors and clinic staff are trained to deal with them. The disease-prevention benefits of getting vaccines are much greater than the possible side effects for almost all children. The only exceptions to this are cases in which a child has a serious chronic medical condition like cancer or a disease that weakens the immune system, or has had a severe allergic reaction to a previous vaccine dose.

Q: Is there a link between vaccines and autism?

A: No. Scientific studies and reviews continue to show no relationship between vaccines and autism.

Some people have suggested that thimerosal (a compound that contains mercury) in vaccines given to infants and young children might be a cause of autism. Others have suggested that the MMR (measles- mumps-rubella) vaccine may be linked to autism. However, numerous scientists and researchers have studied and continue to study the MMR vaccine and thimerosal, and they reach the same conclusion: there is no link between MMR vaccine or thimerosal and autism.

Q: Why are so many doses needed for each vaccine?

A: Getting every recommended dose of each vaccine provides your child with the best protection possible. Depending on the vaccine, your child will need more than one dose to build high enough immunity to prevent disease or to boost immunity that fades over time. Your child may also receive more than one dose to make sure they are protected if they did not get immunity from a first dose, or to protect them against germs that change over time, like flu. Every dose is important because each protects against infectious diseases that can be especially serious for infants and very young children.

Q: What do you think of delaying some vaccines or following a non-standard schedule?

A: Children do not receive any known benefits from following schedules that delay vaccines. Infants and young children who follow immunization schedules that spread out or leave out shots are at risk of developing diseases during the time you delay their shots. Some vaccine-preventable diseases remain common in the United States and children may be exposed to these diseases during the time they are not protected by vaccines, placing them at risk for a serious case of the disease that might cause hospitalization or death.

Q: Why does my child need a chickenpox shot? Isn’t it a mild disease?

A: Your child needs a chickenpox vaccine because chickenpox can actually be a serious disease. In many cases, children experience a mild case of chickenpox, but other children may have blisters that become infected. Others may develop pneumonia. There is no way to tell in advance how severe your child’s symptoms will be.

Before vaccine was available, about 50 children died every year from chickenpox, and about 1 in 500 children who got chickenpox was hospitalized.

Q: My child is sick right now. Is it okay for her to still get shots?

A: Talk with your child’s doctor, but children can usually get vaccinated even if they have a mild illness like a cold, earache, mild fever, or diarrhea. If the doctor says it is okay, your child can still get vaccinated.

Q: Don’t infants have natural immunity? Isn’t natural immunity better than the kind from vaccines?

A: Babies may get some temporary immunity (protection) from mom during the last few weeks of pregnancy, but only for diseases to which mom is immune. Breastfeeding may also protect your baby temporarily from minor infections, like colds. These antibodies do not last long, leaving your baby vulnerable to disease.

Natural immunity occurs when your child is exposed to a disease and becomes infected. It is true that natural immunity usually results in better immunity than vaccination, but the risks are much greater. A natural chickenpox infection may result in pneumonia, whereas the vaccine might only cause a sore arm for a couple of days.

Q: Can’t I just wait to vaccinate my baby, since he isn’t in child care, where he could be exposed to diseases?

A: No, even young children who are cared for at home can be exposed to vaccine preventable diseases, so it’s important for them to get all their vaccines at the recommended ages. Children can catch these illnesses from any number of people or places, including from parents, brothers or sisters, visitors to their home, on playgrounds or even at the grocery store. Regardless of whether or not your baby is cared for outside the home, she comes in contact with people throughout the day, some of whom may be sick but not know it yet.

If someone has a vaccine preventable disease, they may not have symptoms or the symptoms may be mild, and they can end up spreading disease to babies or young children.  Remember, many of these diseases can be especially dangerous to young children so it is safest to vaccinate your child at the recommended ages to protect her, whether or not she is in child care.