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Summary
What are vaccines?
Vaccines are injections (shots), liquids, pills, or nasal sprays that you take to teach the immune system to recognize and defend against harmful germs. The germs could be viruses or bacteria.
Some types of vaccines contain germs that cause disease. But the germs have been killed or weakened enough that they won't make your child sick. Some vaccines only contain a part of a germ. Other types of vaccines include instructions for your cells to make a protein of the germ.
These different vaccine types all spark an immune response, which helps the body fight off the germs. Your child's immune system will also remember the germ and attack it if that germ ever invades again. This protection against a certain disease is called immunity.
Why do I need to vaccinate my child?
Babies are born with immune systems that can fight most germs, but there are some serious diseases they can't handle. That's why they need vaccines to strengthen their immune system.
These diseases once killed or harmed many infants, children, and adults. But now with vaccines, your child can get immunity from these diseases without having to get sick. And for a few vaccines, getting vaccinated can actually give you a better immune response than getting the disease would.
Vaccinating your child also protects others. Normally, germs can travel quickly through a community and make a lot of people sick. If enough people get sick, it can lead to an outbreak. But when enough people are vaccinated against a certain disease, it's harder for that disease to spread to others. The entire community is less likely to get the disease. This is called "community immunity."
Community immunity is especially important for the people who can't get certain vaccines. For example, they may not be able to get a vaccine because they have weakened immune systems. Others may be allergic to certain vaccine ingredients. And newborn babies are too young to get some vaccines. Community immunity can help to protect them all.
Are vaccines safe for children?
Vaccines are safe. They must go through extensive safety testing and evaluation before they are approved in the United States.
Some people worry that childhood vaccines could cause autism spectrum disorder (ASD). But many scientific studies have looked at this and have found no link between vaccines and autism.
Can vaccines overload my child's immune system?
No, vaccines do not overload the immune system. Every day, a healthy child's immune system successfully fights off thousands of germs. When your child gets vaccines, they are getting weakened or dead germs. So even if they get several vaccines in one day, they are being exposed to a tiny amount of germs compared to what they encounter every day in their environment.
When do I need to vaccinate my child?
Your child will get vaccines during well-child visits. They will be given according to the vaccine schedule. This schedule lists which vaccines are recommended for children. It includes who should get the vaccines, how many doses they need, and at what age they should get them. In the United States, the Centers for Disease Control and Prevention (CDC) publishes the vaccine schedule.
Following the vaccine schedule allows your child to get protection from the diseases at exactly the right time. It gives their body the chance to build up immunity before being exposed to these very serious diseases.
Related Issues
- Current Vaccine Shortages and Delays (Centers for Disease Control and Prevention)
- Do Kids Need Vaccines Before Traveling? (Nemours Foundation) Also in Spanish
- Do Vaccines Cause Autism? Is It OK to Skip Certain Vaccines? Get the Facts on These and Other Common Questions (Mayo Foundation for Medical Education and Research) Also in Spanish
- Is There a Connection Between Vaccines and Autism? (Nemours Foundation) Also in Spanish
- Keeping Track of Records (Centers for Disease Control and Prevention)
- Thimerosal and Vaccines (Centers for Disease Control and Prevention)
- Travelers' Health: Vaccine Recommendations for Infants and Children (Centers for Disease Control and Prevention)
- Vaccine Safety: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish
- Vaccines Protect Your Community (Department of Health and Human Services) Also in Spanish
- What Is Herd Immunity? (Nemours Foundation) Also in Spanish
Specifics
- Booster Shots (Nemours Foundation) Also in Spanish
- Immunizations for Preterm Babies (American Academy of Pediatrics) Also in Spanish
- Vaccination Is the Best Protection against Measles (Food and Drug Administration) Also in Spanish
- Vaccine Basics (Centers for Disease Control and Prevention)
- Your Baby's First Vaccines (Centers for Disease Control and Prevention)
Images
- (Vaccine-Preventable Disease) Photo Library (Immunization Action Coalition)
Health Check Tools
- Child and Adolescent Vaccine Assessment Tool (Centers for Disease Control and Prevention) Also in Spanish
Statistics and Research
- FastStats: Immunization (National Center for Health Statistics)
- VaxView Vaccination Coverage (Centers for Disease Control and Prevention)
Clinical Trials
- ClinicalTrials.gov: Childhood Immunization (National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Surveillance for adverse events following immunization in Hebei Province, China, 2018-2020.
- Article: Prediction of incomplete immunization among under-five children in East Africa from...
- Article: Twenty Years of Progress and the Way Forward: Immunization Registry Information...
- Childhood Vaccines -- see more articles
Reference Desk
- Overview of the Immune System (National Institute of Allergy and Infectious Diseases)
Find an Expert
- Centers for Disease Control and Prevention Also in Spanish
- National Vaccine Program (Department of Health and Human Services, Office of Infectious Disease and HIV/AIDS Policy)
Children
- Kid's Guide to Shots (Nemours Foundation) Also in Spanish
- What Can I Do to Ease My Child's Fear of Shots? (For Parents) (Nemours Foundation) Also in Spanish
Teenagers
- Vaccinations for Preteens and Teens (Immunization Action Coalition) - PDF Also in Spanish
- Vaccines for 'Tweens,' Teens and Young Adults (American Academy of Pediatrics) Also in Spanish
Patient Handouts
- Your Baby's First Vaccines: What You Need to Know (Centers for Disease Control and Prevention) - PDF