Table of ContentsView AllTable of ContentsDefinitionWhat Vaccines DoType of VaccinesVaccine Schedules
Table of ContentsView All
View All
Table of Contents
Definition
What Vaccines Do
Type of Vaccines
Vaccine Schedules
The termsimmunizedandvaccinatedare often used interchangeably, but they have different meanings. Vaccination describes the act of receiving a vaccine. Immunization describes the process of becoming immune through vaccination.
Those differences may seem minor. Still, using terms correctly can prevent misunderstandings with your healthcare provider.
Verywell / Mayya Agapova
How Are Vaccination and Immunization Different?
The World Health Organization (WHO) says vaccination and immunization are related terms. But vaccination describes a specific action, while immunization describes a process.
By the WHO definition:
The Centers for Disease Control and Prevention (CDC) offers similar definitions:
What Is Inoculation?
Inoculation (also known asvariolation) is a term coined in the 18th century that describes the practice of introducing a small amount of pus from someone withsmallpoxinto the body of someone without smallpox. The aim was to induce a mild infection that would afford immune protection to the inoculated person.
Vaccination and immunization involve the use of vaccines. It is not the same thing as your body’s response to anatural infectionlike measles or flu.
Although vaccines and natural infections both trigger an immune response in the form of defensiveantibodies, vaccines do so with lower risk and higher reliability.This is because vaccines involve organisms or substances that induce the immune response without causing a disease.
The duration of the protective effect can vary, ranging from several months (such as with the flu vaccine) to a lifetime (such as with the hepatitis B vaccine). For vaccines that don’t afford lifetime protection, revaccination or booster shots may be needed.
Herd immunityoccurs when enough people in a community are vaccinated, minimizing the spread of a disease. This can lead to theelimination of a diseasein certain parts of the world or theeradication of a diseasethroughout the world.
To date, the only disease that has been eradicated from the planet is smallpox.
There are different categories of vaccines that induce immunity in different ways. Some are made with disease-causing microorganisms (pathogens) that have been altered in the lab, while others are entirely man-made.
The six main categories of vaccines are:
What Are Vaccine Schedules?
Avaccine scheduleis a recommended list of vaccines a person should receive to protect against a host of potentially serious infections. The schedule describes which vaccines should be given when and in how many doses. The vaccine schedule starts at birth and continues into adulthood.
In the United States, the Advisory Council on Immunization Practices (ACIP) is the authority tasked with making vaccine schedule recommendations.
The independent panel of experts, housed within the Centers for Disease Control and Prevention (CDC), meets thrice yearly to review scientific data and recommendations from public health organizations like the American Pediatric Association (APA) or the American Academy of Family Physicians (AAFP).
In the United States, ACIP statements are regarded as federal recommendations.
Recommended Vaccine Schedule for Children
These include:
Recommended Vaccination Schedule for Adults
The ACIP recommendations continue into adulthood. Some vaccines are given regularly as boosters while others afford protection against diseases that are more serious in older adults.
How Are Vaccines Approved?Vaccines in the United States get approval from the Food and Drug Administration (FDA). This involves a rigorous, multi-trial process that can take years from start to finish:First, research must show that the vaccine is necessary.Initial testing is performed on animals.Small human studies (called preclinical trials) test the vaccine for safety.At least three phases of large human testing are done.If it’s safe and effective, the vaccine can move on to the FDA’s licensing process.Even after approval, the FDA closely monitors vaccines for any problems and can change or rescind their approval as needed.
How Are Vaccines Approved?
Vaccines in the United States get approval from the Food and Drug Administration (FDA). This involves a rigorous, multi-trial process that can take years from start to finish:First, research must show that the vaccine is necessary.Initial testing is performed on animals.Small human studies (called preclinical trials) test the vaccine for safety.At least three phases of large human testing are done.If it’s safe and effective, the vaccine can move on to the FDA’s licensing process.Even after approval, the FDA closely monitors vaccines for any problems and can change or rescind their approval as needed.
Vaccines in the United States get approval from the Food and Drug Administration (FDA). This involves a rigorous, multi-trial process that can take years from start to finish:
Even after approval, the FDA closely monitors vaccines for any problems and can change or rescind their approval as needed.
Summary
Vaccination gives you immunity to a specific pathogen. Immunization is the process of developing immunity. The word usually refers to immunity through vaccination, but it can occur through infection as well.
Vaccines teach your immune system to recognize and fight specific germs. Herd immunity means too many people are immune for a pathogen to spread. This protects those who aren’t vaccinated.
Vaccines are timed to protect you and your children when you’re most vulnerable to certain illnesses. It’s important to follow the CDC’s vaccine schedule.
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12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.World Health Organization.Immunization.Centers for Disease Control and Prevention.Immunization: the basics.Boylston A.The origins of inoculation.J R Soc Med. 2012 Jul;105(7):309-13. doi:10.1258/jrsm.2012.12k044Biggs AT, Littlejohn LF.Vaccination and natural immunity: advantages and risks as a matter of public health policy.Lancet Reg Health Americas.2023;8:100242.Cedar Sinai.Why some vaccines last a lifetime and others don’t.Centers for Disease Control and Prevention.History and epidemiology of global smallpox eradication.U.S. Department of Health and Human Service.Vaccine types.Centers for Disease Control and Prevention.Advisory Committee on Immunization Practices (ACIP): general committee-related information.Smith JC Hinman AR, Pickering LK.History and evolution of the Advisory Committee on Immunization Practices — United States, 1964–2014.MMWR Morb Mort Wkly Rep. 2014;63(42):955–8.American Academy of Family Physicians.Birth through age 18 immunization schedule.Centers for Disease Control and Prevention.Recommended vaccines for adults.U.S. Food & Drug Administration.Vaccine Development – 101.Additional ReadingZhang L, Wang W, Wang S.Effect of vaccine administration modality on immunogenicity and efficacy.Expert Rev Vaccines. 2015;14(11):1509-23. doi:10.1586/14760584.2015.1081067
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.World Health Organization.Immunization.Centers for Disease Control and Prevention.Immunization: the basics.Boylston A.The origins of inoculation.J R Soc Med. 2012 Jul;105(7):309-13. doi:10.1258/jrsm.2012.12k044Biggs AT, Littlejohn LF.Vaccination and natural immunity: advantages and risks as a matter of public health policy.Lancet Reg Health Americas.2023;8:100242.Cedar Sinai.Why some vaccines last a lifetime and others don’t.Centers for Disease Control and Prevention.History and epidemiology of global smallpox eradication.U.S. Department of Health and Human Service.Vaccine types.Centers for Disease Control and Prevention.Advisory Committee on Immunization Practices (ACIP): general committee-related information.Smith JC Hinman AR, Pickering LK.History and evolution of the Advisory Committee on Immunization Practices — United States, 1964–2014.MMWR Morb Mort Wkly Rep. 2014;63(42):955–8.American Academy of Family Physicians.Birth through age 18 immunization schedule.Centers for Disease Control and Prevention.Recommended vaccines for adults.U.S. Food & Drug Administration.Vaccine Development – 101.Additional ReadingZhang L, Wang W, Wang S.Effect of vaccine administration modality on immunogenicity and efficacy.Expert Rev Vaccines. 2015;14(11):1509-23. doi:10.1586/14760584.2015.1081067
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
World Health Organization.Immunization.Centers for Disease Control and Prevention.Immunization: the basics.Boylston A.The origins of inoculation.J R Soc Med. 2012 Jul;105(7):309-13. doi:10.1258/jrsm.2012.12k044Biggs AT, Littlejohn LF.Vaccination and natural immunity: advantages and risks as a matter of public health policy.Lancet Reg Health Americas.2023;8:100242.Cedar Sinai.Why some vaccines last a lifetime and others don’t.Centers for Disease Control and Prevention.History and epidemiology of global smallpox eradication.U.S. Department of Health and Human Service.Vaccine types.Centers for Disease Control and Prevention.Advisory Committee on Immunization Practices (ACIP): general committee-related information.Smith JC Hinman AR, Pickering LK.History and evolution of the Advisory Committee on Immunization Practices — United States, 1964–2014.MMWR Morb Mort Wkly Rep. 2014;63(42):955–8.American Academy of Family Physicians.Birth through age 18 immunization schedule.Centers for Disease Control and Prevention.Recommended vaccines for adults.U.S. Food & Drug Administration.Vaccine Development – 101.
World Health Organization.Immunization.
Centers for Disease Control and Prevention.Immunization: the basics.
Boylston A.The origins of inoculation.J R Soc Med. 2012 Jul;105(7):309-13. doi:10.1258/jrsm.2012.12k044
Biggs AT, Littlejohn LF.Vaccination and natural immunity: advantages and risks as a matter of public health policy.Lancet Reg Health Americas.2023;8:100242.
Cedar Sinai.Why some vaccines last a lifetime and others don’t.
Centers for Disease Control and Prevention.History and epidemiology of global smallpox eradication.
U.S. Department of Health and Human Service.Vaccine types.
Centers for Disease Control and Prevention.Advisory Committee on Immunization Practices (ACIP): general committee-related information.
Smith JC Hinman AR, Pickering LK.History and evolution of the Advisory Committee on Immunization Practices — United States, 1964–2014.MMWR Morb Mort Wkly Rep. 2014;63(42):955–8.
American Academy of Family Physicians.Birth through age 18 immunization schedule.
Centers for Disease Control and Prevention.Recommended vaccines for adults.
U.S. Food & Drug Administration.Vaccine Development – 101.
Zhang L, Wang W, Wang S.Effect of vaccine administration modality on immunogenicity and efficacy.Expert Rev Vaccines. 2015;14(11):1509-23. doi:10.1586/14760584.2015.1081067
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