Children born during the COVID-19 pandemic are getting fewer vaccines compared to children born in the 2010s.
To control infectious diseases in the US population, the Centers for Disease Control and Prevention (CDC) recommends that all kids get a set of vaccines known as the “combined 7-series” vaccines, by the time they turn 2.
Though trends for the individual vaccines in the series vary, complete vaccination is trending downward: 72.8% of children born in 2020 and 2021 got the full set of seven by 35 months, compared to 74.4% of children born in 2013–2014.
What’s included in the combined 7-series vaccines?
The series includes vaccines to protect against:
- Chickenpox (varicella): 1 or more doses
- Diphtheria, lockjaw (tetanus), and whooping cough (pertussis): 4 or more doses, commonly of the DTaP vaccine
- Hepatitis B: three or more doses
- Hib infections: three to four or more doses, depending on the vaccine
- Measles: one or more doses, commonly of the MMR vaccine
- Pneumococcal diseases: four or more doses, commonly of the PCV vaccine
- Polio: three or more doses
How have childhood vaccination rates changed over time?
Estimated Hib vaccination rates have declined more than the other six vaccines in the series: from 84.8% in children born in 2011 to 80.3% in those born in 2021. This was the only change with statistical significance.
Estimated rates of Polio, MMR, and DTaP vaccination have been relatively stable, declining less than one percentage point over the last decade.
Estimated chickenpox, Hepatitis B, and PCV vaccination rates have each increased from 2011. Children born in 2021 were vaccinated against chickenpox by age 3 at a rate of 94.4% (the highest of any vaccine in 2021) an increase from 92.7% in 2011.
Chickenpox, polio, MMR, and Hepatitis B vaccination rates have been above 91.0% since 2011. DTaP, PCV, and Hib rates were lower than 90.0% in that same time.
The combined 7-series vaccination rate — historically lower than the rates of its individual components — reached a high of 76.1% 2018, then fell to 72.2% for children born in 2021.
Why is the combined 7-series rate lower than the rates of the individual vaccines? Fewer children have received every single dose of all seven vaccines, even if they’re getting vaccinated for some of them; the full combined 7-series requires administration of all recommended doses.
The CDC attributes the lower vaccination rate for children born in 2020–21 to disruptions to the COVID-19 pandemic, and to changes in exemption policies in childcare facilities.
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Have changes in vaccination rates impacted infection numbers?
The estimated DTaP vaccination rate peaked in 2018 at 89.3% and dropped to 87.0% in 2021. The DTaP vaccine protects kids against whooping cough, among other things. Whooping cough cases reportedly increased in December 2024 compared to 2023, but case numbers are now returning to pre-pandemic levels and were temporarily lower during the pandemic, when students were masking and/or going to school remotely.
The rate for MMR, which protects against measles, mumps, and rubella, decreased from a 2018 peak of 94.7% to 93.1% in 2021. The number of measles cases reported between January 1 and August 15, 2024 — 219 — exceeded the annual number of cases reported from 2020 to 2023.
Which vaccines are kids most likely to get?
Kids born in 2020 and 2021 are most likely to be vaccinated against polio (93.3% of kids) and chickenpox (93.3%). Over 90% of children are fully vaccinated against MMR (92.9%) and Hepatitis B (92.6%) by age 3.
Nearly three-quarters (72.8%) of children completed the full combined 7 series vaccines before they turned 3 years old.
Which states have the highest vaccination rates?
As of 2023, the highest rates of combined 7-series vaccinations were in:
- Massachusetts (92.0%)
- Connecticut (89.7%)
- Rhode Island (84.1)
- New Hampshire (82.8%)
- North Dakota (80.6%)
Like all states, Massachusetts has statewide vaccine requirements for children of all ages, mandating vaccination for enrollment in childcare and preschool. However, Massachusetts is the only state with a vaccination rate higher than 90.0%.
Four of the five states with the highest vaccination rates are in the northeast. Although vaccination requirements are set and maintained at the state level, vaccine rates and exemptions tend to cluster geographically.
Which states have the lowest vaccination rates?
As of 2023, the lowest combined 7-series vaccination rates were in:
- Montana (62.4%)
- Nebraska (62.8%)
- Alaska (64.1%)
- California (65.5%)
- Georgia (66.1%)
Some states, including Montana, have laws prohibiting differential treatment based on vaccination status. Daycares and schools can still require completion of Montana’s childcare attendance vaccine requirements, which align with the combined 7-series.
Parents may still request non-medical exemptions for their children. The national non-medical vaccine exemption rate for kindergarteners increased from 1.9% for the 2020–21 school year to 3.1% for 2023–24.
In the 2023–24 school year, the CDC reported that vaccine exemptions increased among kindergarteners to 3.3% from 3.0% the previous school year. Exemptions can be medical, religious, and philosophical.
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Read data analyses written by the USAFacts team.
Page sources and methodology
All of the data on the page was sourced directly from government agencies. The analysis and final review was performed by USAFacts.
Centers for Disease Control and Prevention
Vaccination Coverage among Young Children (0-35 Months)
