An updated analysis with data for the 2023-24 school year is now available.

Routine vaccination rates for kindergarten children ticked down during the COVID-19 pandemic and have yet to rebound while exemptions from school vaccination requirements have increased, likely contributing to a recent surge in measles cases. At the same time, vaccine hesitancy, fueled in part by vaccine misinformation, increased during the pandemic, and public opinion on vaccine requirements has become increasingly partisan. Vaccine policies have emerged as an election issue, with both former President Trump and Independent candidate Robert F. Kennedy (RFK) Jr. embracing anti-vaccination attitudes and contributing to vaccine misinformation. This is in sharp contrast to current President Biden who has supported vaccine mandates and taken action to expand access to vaccines for both children and adults. This issue brief further explores this changing landscape by examining the latest trends in children’s routine vaccination rates, the factors contributing to recent vaccination trends, and policy approaches to increasing vaccination rates as children head into a new school year. Key takeaways include:

  • The share of kindergarten children up to date on their state-required vaccinations has not rebounded to pre-pandemic levels, and nearly three-quarters of states had measles, mumps, rubella (MMR) vaccination rates below the Healthy People 2030 “target” rate (95%) for the 2022-2023 school year. Further, 12 states and D.C. reported rates below 90% compared with only three states in the 2019-2020 school year.
  • At the same time, the share of kindergarten children with a vaccine exemption has increased nationally and for most (36) states since the pandemic began. For the 2022-2023 school year, 10 states had exemption rates over 5%, meaning it was not possible for those states to reach coverage rates at or above 95%. Higher exemption rates are associated with lower vaccination coverage rates, meaning states with more children claiming exemptions report lower vaccination coverage rates.
  • While both the influenza (flu) and COVID-19 vaccines are recommended for children, flu vaccination rates were over three times higher than COVID-19 vaccination rates for children. Similar to state-required vaccination rates, children’s flu vaccination rates declined during the pandemic and has yet to rebound back to pre-pandemic levels.
  • There are a number of factors contributing to recent vaccination trends, including shifts in public opinion and rising vaccine hesitancy since the pandemic began, likely fueled by vaccine misinformation. There are a number of policy options and strategies that can be used to increase vaccination rates, including leveraging Medicaid to facilitate access to vaccines for low-income children.

What are recent trends in children’s routine vaccination rates?

The share of kindergarten children up to date on their vaccinations ticked down during the pandemic and has yet to rebound back to pre-pandemic levels. Data collected and aggregated annually by the CDC from state and local immunization programs found that, during the 2022-2023 school year, 93% of kindergarteners had been vaccinated with all state-required vaccines, including MMR, DTaP (diphtheria, tetanus, and acellular pertussis), polio, and varicella. This is similar to the previous school year but lower than pre-pandemic levels (95%). For the third year in a row, the MMR vaccination rate fell below the Healthy People 2030 “target” rate of 95%, the level needed to prevent community transmission of measles, a highly contagious and life-threatening virus. This means approximately 250,000 school children were unvaccinated and unprotected against measles, and research shows the more unvaccinated children in a school, the larger risk of an outbreak becomes. While noting that widespread measles transmission risk remains low, the Centers for Disease Control and Prevention (CDC) reported 97 cases of measles in the first quarter of 2024, which is seventeen times more than the number in the first quarter of 2023.

Nearly three-quarters (37) of states had MMR vaccination rates below the “target” rate of 95% for the 2022-2023 school year, an increase from 28 states during the 2019-2020 (pre-pandemic) school year. Further, 12 states and D.C. reported rates below 90% for the 2022-2023 school year; in the 2019-2020 school year, only three states had MMR vaccination rates below 90%. Overall, MMR coverage rates among kindergarteners for the latest school year ranged from 81.3% in Idaho to 98.4% in Mississippi. There can also be variation in vaccination coverage within states, and, when there are clusters of unvaccinated people within a specific community, the risk of an outbreak is higher, as occurred in New York City in 2018-2019.

Changes in state vaccination policies can have implications for children’s vaccination rates. As of 2023, all states and DC require children to be vaccinated against certain diseases, including MMR, in order to attend public schools, though exemptions are allowed in certain circumstances. All states allow a medical exemption, and 46 states (including D.C.) allow for a religious or personal belief exemption (or both). In recent years, some groups and state legislators have pushed to relax requirements and expand vaccine exemptions for school children. For example, some states have proposed requiring schools to include exemption information in all communications about vaccines, eliminating non-medical exemptions in child-care settings, and establishing a children’s vaccination Bill of Rights that emphasizes religious freedom. While many of these efforts have been unsuccessful or are still pending, some bills have become state law. Debate and hesitancy over COVID-19 vaccine mandates has spilled over into attitudes towards requiring vaccines for public schools, likely increasing exemptions and challenges to school vaccine requirements.

As vaccination rates for kindergarten children slightly declined, the share of kindergarten children with an exemption from one or more required vaccination slightly increased. The share of children claiming an exemption from one or more vaccinations rose from 2.5% in the 2019-2020 (pre-pandemic) school year to 3.0% in the 2022-2023 school year, the highest national exemption rate to date. While a seemingly very small increase, any increases in exemptions limit the overall share of children able to be vaccinated and make it more difficult to reach vaccination rate goals. Non-medical exemptions accounted for most of the exemptions. Non-medical exemptions increased from 2.2% to 2.8% while medical exemptions actually declined slightly from 0.3% to 0.2% from 2020-2021 to 2022-2023. The 2020-2021 school year was the lowest point for exemptions claimed during the pandemic era, with the share of children reporting any exemption dipping to 2.2% before rising to 3.0% by the 2022-2023 school year.

Overall, most states (36) have experienced an increase in the share of kindergarteners claiming an exemption for one or more vaccines since the pandemic began. Ten states in the 2022-2023 school year had exemption rates over 5%, meaning those states could not reach vaccination coverage rates at or above 95% even if all non-exempt children were vaccinated. However, rates shown here are for exemptions to one or more vaccines, so potentially achievable coverage rates could vary by vaccine type. In the reporting of this data, the CDC notes they did not asses the cause of the rise in exemptions, meaning the increases could mean a rise in vaccine hesitancy or an increase in issues accessing vaccines. Higher exemption rates are associated with lower vaccination coverage rates, meaning states with more children claiming exemptions report lower vaccination coverage rates. Studies have also shown that increases in exemption rates are associated with increased risk for disease outbreaks.

The impact of the pandemic on vaccination rates for other age groups (beyond kindergarteners) is more mixed, but data show widening disparities. The latest data from a CDC survey of teens ages 13-17 (National Immunization Survey (NIS) -Teen) shows that vaccination coverage rates have lagged for some birth cohorts but not others. The latest data for young children (aged 24 months) from another CDC survey (NIS – Child) shows that overall vaccination rates remained stable during the pandemic but disparities persisted, with the gap in vaccination rates between children living below poverty and children with higher household incomes widening. Another literature review found pandemic-related declines in routine vaccinations across a number of age groups and noted that the pandemic exacerbated existing disparities in vaccination rates.

What are recent trends in COVID-19 and flu vaccination rates?

Flu vaccination rates for children are over three times higher than COVID-19 vaccination rates. While both the flu and COVID-19 vaccines are included in the Advisory Committee on Immunization Practices (ACIP) recommended pediatric immunization schedule, they are not required for school attendance, and some states have even banned student COVID-19 vaccine mandates. The cumulative share of children ages six months through 17 with a flu vaccine during the 2023-2024 season was 54% while share with the updated 2023-2024 COVID-19 vaccine was 15%. Some of this variation in uptake may reflect parental views and concerns. KFF’s COVID-19 Vaccine Monitor from September 2023 found most parents said they would not get their child the new COVID-19 vaccine including six in ten parents of teenagers (those between the ages of 12 and 17), and two-thirds of parents of children ages 5 to 11 (64%) and ages 6 months to 4 years old (66%). Larger shares of parents said they were confident in the safety of both the flu vaccine (68%) and the RSV vaccine (63%) compared to the COVID-19 vaccine (48%). Further, overall children’s flu vaccination coverage declined during the pandemic and has yet to rebound back to pre-pandemic levels.

What factors are contributing to recent trends in children’s routine vaccination trends?

There are a number of factors contributing to recent vaccination trends, including shifts in public opinion and rising vaccine hesitancy, potentially fueled by vaccine misinformation. A KFF Health Misinformation Tracking Poll in March 2024 found that about one in five parents had heard the false claim that a measles vaccine is more dangerous than getting the measles. While most of the public correctly viewed the claim as probably or definitely false, a majority expressed at least some uncertainty. This echoes findings of previous KFF research and highlights the pervasiveness of false and inaccurate information and its impact on vaccination rates. While confidence in vaccines remained high, KFF polling in September 2023 found that three in ten adults said parents should be able to decide not to vaccinate their children against MMR, even if that may create risks for others. This was up from 16% who said the same in an October 2019 Pew Research Center poll. While vaccine hesitancy has always been a challenge, early data show misinformation related to the COVID-19 vaccine increased vaccine hesitancy and may be impacting broader vaccine uptake.

Views and refusal of childhood vaccines have also become more partisan since the COVID-19 pandemic. The same KFF poll found 40% of Republicans said parents should be able to decide not to vaccinate their children (up from 20% in 2019), compared with 14% of Democrats. Further, former Republican President Donald Trump is the first president to openly support anti-vaccination attitudes and share vaccine misinformation. In his recent campaigning, Trump has continued to share anti-vaccine attitudes and stated he will not “give one penny to any school that has a vaccine mandate” (his campaign later said he meant COVID-19 mandates only). Independent candidate RFK Jr. also has a long record of opposing immunizations and spreading vaccine misinformation, making candidate vaccine attitudes one of many key topics this election.

In addition to rising vaccine hesitancy, disruptions that led to missed or delayed preventive care appointments early in the pandemic likely contributed to declines in vaccination rates. For example, for children enrolled in Medicaid or CHIP, well-child visit rates declined during the pandemic, and declines in vaccination rates may be, in part, associated with declines in well-child visits. Even before the pandemic, many children in Medicaid or CHIP did not receive a well-child visit within a year period, signaling children may also be experiencing barriers to accessing care.

What are policy options to increase vaccination rates?

There are a number of policy options and strategies that can be used to increase vaccination rates, including media outreach, incentives, parent-friendly websites, school-based vaccination clinics, and school vaccination requirements. Preventive care visits are also an important component when addressing routine vaccination rates, and efforts to promote access to care and increase well-child visits could potentially improve vaccination rates. To increase access to vaccines, some states have expanded the scope of pharmacists’ practice to include administration of routine vaccinations for children, and others are working to address rural health workforce shortages. Establishing and fostering trust between parents and providers, community leaders, and public health departments can also help to combat vaccine hesitancy. KFF polling has found pediatricians are considered highly trusted sources of information by parents, and strong provider recommendations can help reduce disparities in vaccination coverage. School vaccine mandates and limiting exemptions can also be a tool to increase vaccine uptake, though recent trends show more states are working to loosen exemption requirements.

Medicaid covers four in ten children in the U.S., including 8 in 10 children living in poverty and over half of Black, Hispanic, and American Indian and Alaska Native (AIAN) children, making Medicaid an important tool for facilitating access to vaccines for children and reducing disparities in vaccination rates. There have been a number of recent state and federal actions aimed at improving access to care in Medicaid and CHIP, which could in turn help provide timely access to vaccines. This includes provisions to strengthen access to comprehensive health services, expand Medicaid coverage of school-based care, and promote stable coverage for children. The federally funded Vaccines for Children program (VFC) provides vaccines at no cost for children who are uninsured or underinsured, AIAN children, and children with Medicaid, and Biden’s latest budget also proposes expanding the program to children in separate CHIP programs.

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