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Childhood Vaccinations

By

Michael J. Smith

, MD, MSCE, Duke University School of Medicine

Last full review/revision Jul 2020| Content last modified Jul 2020
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Children should be vaccinated to protect them against infectious diseases. Vaccines contain either noninfectious fragments of bacteria or viruses or whole forms of these organisms that have been weakened so that they do not cause disease. Giving a vaccine (usually by injection) stimulates the body's immune system to defend against that disease. Vaccination produces a state of immunity to disease and is thus sometimes termed immunization (see also Overview of Immunization Overview of Immunization Immunization enables the body to better defend itself against diseases caused by certain bacteria or viruses. Immunity (the ability of the body to defend itself against diseases caused by certain... read more ).

Vaccine Effectiveness

Vaccines have eliminated smallpox and have nearly eliminated other infections, such as polio Polio Polio is a highly contagious, sometimes fatal enterovirus infection that affects nerves and can cause permanent muscle weakness, paralysis, and other symptoms. Polio is caused by a virus and... read more , that were once common childhood scourges in the United States. Despite this success, it is important for health care practitioners to continue to vaccinate children. Many of the diseases prevented by vaccination are still present in the United States and remain common in other parts of the world. For example, in 2019, there were 1,282 cases of measles, mostly in unvaccinated people. This is the greatest number of measles cases in the United States since 1992. These diseases can spread rapidly among unvaccinated children, who, because of the ease of modern travel, can be exposed even if they live in areas where a disease is not common.

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Vaccine Safety

No vaccine is 100% effective and 100% safe. A few vaccinated children do not become immune, and a few develop side effects. Most often, the side effects are minor, such as pain at the injection site, a rash, or a mild fever. Very rarely, there are more serious problems.

Vaccines are continuously undergoing improvements to ensure safety and effectiveness. Improvements include the use of

The oral polio vaccine, which is made of a live, weakened virus, can cause polio if the weakened virus mutates, which happens once in every 2.4 million children. Although this risk is extremely low, it has led doctors in the United States to completely switch to the injectable polio vaccine.

Vaccine Adverse Event Reporting System (VAERS)

Before a new vaccine can be licensed, it, like any medical product, is tested in controlled clinical trials How Doctors Try to Learn What Works Doctors have been treating people for many thousands of years. The earliest written description of medical treatment is from ancient Egypt and is over 3,500 years old. Even before that, healers... read more . Such trials compare the new vaccine to a placebo or to a previously existing vaccine for the same disease. Such trials show whether the vaccine is effective and identify common side effects. However, some side effects are too rare to be detected in any reasonably sized clinical trial and do not become apparent until after a vaccine is used routinely in many people. Thus, a surveillance system called the Vaccine Adverse Event Reporting System (see VAERS) was created to monitor the safety of vaccines that are used in the general public.

VAERS collects reports from people who believe that they had a side effect after a recent vaccination and from health care practitioners who identify certain possible side effects after a vaccine was given, even if they are unsure the effects are related to the vaccine. Thus, the existence of a VAERS report is not proof that a vaccine caused a certain side effect. VAERS is simply a system for collecting data about things that might be side effects. Then, the Food and Drug Administration (FDA) can further evaluate the concern by comparing how often the possible side effect occurred in people who were vaccinated to how often it occurred in people who were not vaccinated.

National Vaccine Injury Compensation Program

To help people evaluate the risks and benefits of vaccination, the federal government requires doctors to give parents a Vaccine Information Statement each time a child is vaccinated. Also, the National Vaccine Injury Compensation Program has been established to compensate people with proven vaccine-related injuries. This program was established because doctors and health authorities want as many children as possible to be protected from life-threatening diseases. When considering the risks and benefits of vaccination, parents must remember that the benefits of vaccination far outweigh the risks.

More Information about Childhood Vaccinations

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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Childhood Vaccinations
Which of the following is another term for vaccination?
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