Immunization

On this page

Basics

• Summary
• Start Here
• Diagnosis and Tests

Learn More

• Related Issues

See, Play and Learn

• Images
• Health Check Tools
• Videos and Tutorials

Research

• Statistics and Research
• Clinical Trials
• Journal Articles

Resources

• Reference Desk
• Find an Expert

For You

• Children
• Women
• Older Adults
• Patient Handouts

Summary

Shots may hurt a little, but the diseases they can prevent are a lot worse. Some are even life-threatening. Immunization shots, or vaccinations, are essential. They protect against things like measles, mumps, rubella, hepatitis B, polio, tetanus, diphtheria, and pertussis (whooping cough). Immunizations are important for adults as well as children.

Your immune system helps your body fight germs by producing substances to combat them. Once it does, the immune system "remembers" the germ and can fight it again. Vaccines contain germs that have been killed or weakened. When given to a healthy person, the vaccine triggers the immune system to respond and thus build immunity.

Before vaccines, people became immune only by actually getting a disease and surviving it. Immunizations are an easier and less risky way to become immune.

Start Here

• Get Shots to Protect Your Health (Adults Ages 19 to 49) (Office of Disease Prevention and Health Promotion) Also in Spanish
• Recommended Adult Immunization Schedule for ages 19 years or older, United States, 2019 (Centers for Disease Control and Prevention)
• Vaccine Basics (Department of Health and Human Services)
• Vaccines for Adults: Which Do You Need? (Mayo Foundation for Medical Education and Research) Also in Spanish
• Vaccines.gov (Department of Health and Human Services) Also in Spanish

Diagnosis and Tests

• Screening Checklist for Contraindications to Vaccines for Adults (Immunization Action Coalition) - PDF Also in Spanish

Related Issues

• Community Immunity: How Vaccines Protect Us All (National Institutes of Health)
• Heart Disease, Stroke, or Other Cardiovascular Disease and Adult Vaccination (Centers for Disease Control and Prevention) Also in Spanish
• HIV Infection and Adult Vaccination (Centers for Disease Control and Prevention)
• Keeping Your Vaccine Records up to Date (Centers for Disease Control and Prevention) Also in Spanish
• Liver Disease and Adult Vaccination (Centers for Disease Control and Prevention)
• There Are Vaccines You Need as an Adult (Centers for Disease Control and Prevention) Also in Spanish
• Vaccinations and Flu Shots for People with Cancer (American Cancer Society)
• Vaccinations for Adults with Diabetes (Immunization Action Coalition) - PDF
• Vaccine Safety: MedlinePlus Health Topic (National Library of Medicine)
• Weakened Immune System and Adult Vaccination (Centers for Disease Control and Prevention)
• What Would Happen If We Stopped Vaccinations? (Centers for Disease Control and Prevention) Also in Spanish
• What's in Vaccines? (Centers for Disease Control and Prevention)
• Who Should Not Get Vaccinated with These Vaccines? (Centers for Disease Control and Prevention)

Images

• Vaccine-Preventable Disease Photos (Immunization Action Coalition)

Health Check Tools

• What Vaccines Do You Need? (Centers for Disease Control and Prevention) Also in Spanish

Videos and Tutorials

• Vaccines (Medical Encyclopedia) Also in Spanish

Statistics and Research

• Safeguarding Our Health: Vaccines Protect Us All (National Institutes of Health) Also in Spanish
• VaxView: Vaccination Coverage [data] in the U.S. (Centers for Disease Control and Prevention)

Clinical Trials

• ClinicalTrials.gov: Vaccines (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Mitigating Coronavirus Induced Dysfunctional Immunity for At-Risk Populations in COVID-19: Trained...
• Article: Safety and immunogenicity of an rAd26 and rAd5 vector-based heterologous prime-boost...
• Article: IMRAS-A clinical trial of mosquito-bite immunization with live, radiation-attenuated P. falciparum...
• Immunization -- see more articles

Reference Desk

• Glossary of Vaccine Terms (Centers for Disease Control and Prevention)
• 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 Institute of Allergy and Infectious Diseases
• Travelers' Health: Destinations (Centers for Disease Control and Prevention)
• Vaccine Finder (Department of Health and Human Services)

Children

• Childhood Immunization: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

Women

• Immunization and Pregnancy (Centers for Disease Control and Prevention) - PDF
• Vaccines and Pregnancy (Organization of Teratology Information Specialists) Also in Spanish

Older Adults

• Shots for Safety (National Institute on Aging)

Patient Handouts

• Immunizations - diabetes (Medical Encyclopedia) Also in Spanish