Immunization Schedule for Kids: Vaccine Guide by Age

You’d probably do anything to protect your children, but is following their immunization schedule near the top of your list? Over the centuries, we’ve battled numerous diseases, but immunizations are responsible for helping to eradicate some diseases that are now only found in a few countries. Once the science of immunizations and vaccine schedules became available, people realized that we don’t need to fear certain diseases, and we’ve extended people’s lifespans. This holds true as long as we actually receive those vaccines and develop “herd immunity,” which is the concept that if enough people are immune to a disease, it’s harder for an infection to spread if it makes its way to a community.^6,7

In this article, we’ll discuss how vaccines work, explore what types of diseases they prevent, and provide a children’s immunization schedule so you know what shots your little one needs and when to get them.

What Are Vaccines, and How Do They Work?

Vaccines contain a dead or weakened form of a disease.⁹ Once put into the body, they teach it to recognize certain germs or foreign invaders. If you’re ever exposed, your body’s immune system will kick into high gear to attack and destroy the invader and protect you from the disease before you get sick.^9,10 Vaccines on the childhood immunization schedule are safe because they’re tested rigorously, sometimes for up to 15 years, before the Food and Drug Administration (FDA) approves them.¹¹

Some childhood vaccinations used for decades have completely erased diseases like smallpox and have almost eradicated polio.¹² The polio virus has three strains; strain two was eliminated in 1999, and strain three was eliminated in 2020.¹³ According to the World Health Organization (WHO), in 2022, the polio virus strain one was only found in two countries: Pakistan and Afghanistan.^1,3 To date, we have vaccines that can prevent 30 life-threatening illnesses, including one (HPV vaccine) to help prevent cancer.^1,2,14

Vaccine Effectiveness Differs

Organizations like the WHO and the American Academy of Pediatrics (AAP) say that our current children’s immunizations have an 85-99% effectiveness in preventing disease if the immunizations are administered correctly according to the current children’s immunization schedule from the Centers for Disease Control and Prevention (CDC).^3,15 But the annual vaccines, such as influenza (flu), have a different effectiveness rate: between an average of 40% and 60%.¹⁶ The influenza virus has countless, ever-changing strains, so the vaccine effectiveness changes yearly.¹⁷ Even if the influenza vaccine doesn’t prevent illness, it typically decreases the rate of severe disease and the need for hospitalization, especially for higher-risk individuals.^3,18

General Vaccine Side Effects

Any vaccine can have basic side effects such as redness, soreness, slight swelling at the injection site, tiredness that day or for the next few days, fussiness in children, a slightly elevated temperature, and loss of appetite.¹⁹ Other rarer side effects are also possible with vaccines. Each vaccine has these side effects listed on the Vaccination Information Statements (VIS), which the CDC produces.^5,20

Vaccine Information Statements

Every time your child receives a vaccine, federal law dictates that the provider must give the parents a Vaccine Information Statement (VIS) for each vaccine.^5,20 These handouts contain important information such as:^5,20

• The name of the vaccine
• What disease it prevents
• Why it’s important to prevent that disease
• How the disease is spread
• Information you should give to your provider to make sure it’s safe to receive the vaccine
• Possible side effects and what to do if you see them

There’s also a section titled “The National Vaccine Injury Compensation Program.” This program allows you to receive compensation in the rare event that a vaccine injures your child.²¹ You must report the information to the Vaccine Adverse Event Reporting System (VAERS) website.

The CDC updates the VIS handouts when new information about a vaccine becomes available. You can find these VIS handouts on the CDC website. I highly recommend that you review these and have the doctor answer all your questions about each vaccine, since most vaccines are given more than once to your child.²² So, you’ll see the same vaccines repeatedly, along with the same VIS information.

Diseases and Their Vaccines

Here’s a short description of each vaccine and what disease it prevents. In addition to these possible symptoms, most of these diseases can also be associated with death and serious disability:^1,2,53

• Hepatitis B: This is a liver disease with fever, vomiting, and jaundice that can lead to lifelong illness and liver failure.²³
• Rotavirus: This is a gastrointestinal virus that gives you severe diarrhea, typically for several days to a week or a little longer.^24,25
• Diphtheria: Diphtheria is a bacterial infection that can lead to heart damage (or even heart failure), difficulty breathing, and paralysis in certain muscles, among other symptoms.²⁶
• Pertussis: Also known as whooping cough, this lung infection causes uncontrollable, violent coughing that makes it hard to breathe, eat, or drink. In young babies/children, it can cause pneumonia, convulsions, and brain damage.^27,28,29
• Tetanus: This disease involves painful stiffening of the muscles and can lead to serious health problems, like being unable to open the mouth and having trouble swallowing and breathing.^30,31
• Haemophilus influenzae type b (Hib): This affects the lungs with pneumonia and can cause meningitis, as well as ear infections and sinus infections.^32,33
• Pneumococcal disease: This lung disease can lead to a blood infection, meningitis, difficulty breathing, or infections of the joints, bones, and lining of the heart.^34,35
• Polio: Polio is an infectious disease that affects the nervous system and can cause total paralysis.³⁶
• Influenza: Commonly called the flu, this respiratory illness is caused by the influenza virus. It can lead to pneumonia, bronchitis, ear infections, and sinus infections.^37,38
• Measles: Also called rubeola, this disease involves symptoms like a fever, rash, and dry cough. It can lead to complications like pneumonia and encephalitis (brain inflammation).³⁹
• Mumps: Caused by a virus, this disease has symptoms like swollen salivary glands under the jaw, fever, muscle aches, and tiredness. Mumps can also lead to deafness, swelling of the brain and/or spinal cord covering, and painful swelling of the testicles or ovaries.^40,41
• Rubella: Also called German measles, this illness is caused by a virus and involves symptoms like a fever, rash, and swollen lymph nodes.⁴² Rubella can cause severe fetal issues in pregnant women, including birth defects and miscarriage.^42,43
• Chickenpox: This illness involves symptoms such as an itchy rash, a fever, and infected blisters. Chickenpox can lead to pneumonia, inflammation of the blood vessels, encephalitis, and infection of the skin, bones, or joints. Years later, people can also develop a painful rash known as “shingles.”^44,45
• Hepatitis A: This is a liver disease with symptoms like a low-grade fever, vomiting, diarrhea, and stomach pain. In rare cases, it can even lead to acute liver failure.⁴⁶
• Human papillomavirus (HPV): HPV is a virus that can lead to genital warts and genital cancers.^47,48
• Meningococcal disease: This can cause symptoms like fever, headache, stiff neck, and rash, and it can lead to seizures, stroke, and other nervous system issues.^49,50

Children’s Immunization Schedule

The child and adolescent immunization schedules are broken down by age group:^1,2,51,52

1. First group: Birth through age 6
2. Second group: Age 7 to age 18

The first group is the busiest of the two because young children receive vaccines to give them the most protection at their most vulnerable age and, often, lifelong immunity.^10,51 But remember that many of these vaccines are given as combinations, sometimes with two or more vaccines safely in the same dose (read: one poke!). These combination vaccines not only help to limit the number of injections given at one time to your child, but they also help determine the vaccine schedule itself.⁵⁵ Additionally, a little wiggle room is built into the vaccine schedules to make up for missed doses.

Commonly Used Children’s Immunization Schedule by Age

Most pediatricians follow this common vaccine schedule. This list shows the number of actual shots your child will receive by age and how many shots they need to complete each series.⁸ (Note: Several immunization shots combine a few into one, so there might be two or three in one shot, for instance.)

Birth

• Hepatitis B #1 (Hepatitis B vaccine is a three-shot series.)

2 Months Old

There are only two to three shots:

• Rotavirus #1 (Rotavirus is a two- or three-dose oral vaccine series.)
• DTaP #1 (Diphtheria, tetanus, and acellular pertussis is a five-dose series.)
• Hib #1 (Haemophilus influenzae type b is a three- or four-dose series.)
• IPV #1 (Inactivated polio virus is a four-dose series.)
• PCV #1 (Pneumococcal conjugate is a four-dose series.)
• Hep B #2

4 Months Old

There are only two shots, unless you missed the first Hep B dose at birth, in which case there are three:

• Rotavirus #2
• DTaP #2
• Hib #2
• IPV #2
• PCV #2
• Hep B #2 (if missed at birth)

6 Months Old

There are two to three shots, four if they need the influenza shot:

• Rotavirus #3
• DTaP #3
• Hib #3
• IPV #3
• PCV #3
• Hep B #3
• Influenza #1 (This is an annual vaccine, with the first annual dose for children 6 months to 8 years old as a two-dose series given at least four weeks apart. It’s a seasonal vaccine, typically only available during the months of September through April or May.)

9 Months Old

There are no shots, unless it’s the season for influenza shots:

• Influenza #2

12 Months Old

There are three shots, four if they need the influenza shot:

• Hep A #1 (Hepatitis A is a two-dose series.)
• MMR #1 (Measles, mumps, rubella is a two-dose series.)
• Varicella #1 (The chickenpox vaccine is a two-dose series.)
• Influenza if needed

15 Months Old

There are three shots, four if they need the influenza shot:

• DTaP #4
• Hib #4
• PCV #4
• Influenza if needed

18 Months Old

There’s only one shot, two if they need the influenza shot.

• Hep A #2
• Influenza if needed

19-23 Months Old

Make up for missed doses and do the influenza shot if they need it.

2-3 Years Old

Make up for missed doses and do the influenza shot if they need it.

4-6 Years Old

There are two shots, three if they need the influenza shot:

• DTaP #5
• IPV #4
• Varicella #2
• MMR #2

7-10 Years Old

Make up for missed doses and influenza as needed.

11-12 Years Old

There are three shots, four if they need the influenza shot:

• Tdap booster (This is given every 10 years for life unless there’s a recent injury.)
• MenACWY #1 (Meningococcal meningitis; covers virus groups A, C, Y, and W)
• HPV #1 (Human papillomavirus is a two-dose series, unless the first dose is given at age 15 or older, in which case it’s a three-dose series.)

13-15 Years Old

There’s one shot, two if they need the influenza shot:

• HPV #2

16-21 Years Old

• MenACWY #2 (Meningococcal meningitis)
• Men B (Meningococcal meningitis; covers virus group B; typically only needed for select individuals, including Army/Navy recruits)
• HPV #2 if not given yet

The Children’s Immunization Schedule Updates Yearly

The CDC annually recommends the children’s immunization schedule. They also list diseases that these vaccines prevent and why we should prevent them.^8,53

Generally, the Advisory Committee on Immunization Practices (ACIP) gives annual recommendations to update the childhood immunization schedule once a year.⁴ According to the CDC, the ACIP comprises 15 experts who meet three times a year to review research, scientific data, statistics on safety and effectiveness, and clinical trial information to determine immunization recommendations.^4,56 These meetings are available to the public online via webcast. The ACIP also participates in ongoing work groups related to vaccines and immunization schedules throughout the year.⁵⁴

[Note: In my opinion, the ACIP may not be as reliable in this current administration (2024-2028).]

How Will the Recent CDC/ACIP Changes Affect Vaccine Availability?

Recently, there has been a cut in National Institutes of Health (NIH) funding, changes in COVID vaccine schedules, and the replacement of the entire ACIP committee. These changes could bring back diseases that have been all but eradicated for decades in the United States. Parents are urged to listen to their pediatricians and state/national experts on immunizations at this time. I believe the current children’s immunization schedule (2024-2025 version) should be used regardless of how the schedule may change this year and in the coming years under the current administration. So, continue to vaccinate your children based on their pediatrician’s advice and consult evidence-based vaccine resources, including immunize.org and healthychildren.org.

The Bottom Line

Wouldn’t you do anything to protect your children? Even when you were pregnant, you did everything you could to protect your unborn child. You completed every test, measurement, doctor’s visit, ultrasound, blood draw, etc. You learned how to feed and bathe a new baby and studied other incredibly helpful information. Your children’s immunization schedule may not be near the top of the list, but it should be!

Immunizations may not be fun, but they’re one of the most powerful tools we have to protect our kids. Staying informed and following your pediatrician’s guidance helps ensure your child stays safe and healthy for years to come.