Vaccine requirements for K-12 schools
Vaccine requirements for K-12 schools require immunization documentation or proof of immunity due to prior infection for school attendance for all students in kindergarten through 12th grade1. All states require vaccinations for measles, mumps, rubella (MMR); diphtheria, tetanus, acellular pertussis (DTaP); polio; and chickenpox (varicella)2; all also require a tetanus, diphtheria, and acellular pertussis booster (TDaP) for entry into later grades3. Requirements for other vaccines vary by state. Each state provides medical exemptions for those who cannot safely receive a vaccine, and most states offer nonmedical exemptions (NMEs) for religious or personal beliefs2. Some states designate which vaccinations are required by statute while other states designate requirements through administrative rules1. Comprehensiveness of requirements, number of doses required, procedures to obtain exemptions (medical and nonmedical), and enforcement vary1, 4. Most laws apply to both public and private schools, and several cover homeschooling as well5.
While vaccines do sometimes have side effects, severe adverse events remain very rare. Vaccines do not cause autism6.
What could this strategy improve?
Expected Benefits
Our evidence rating is based on the likelihood of achieving these outcomes:
Increased vaccination
Reduced vaccine preventable disease
What does the research say about effectiveness?
There is strong evidence that vaccine requirements for K-12 schools increase vaccine coverage and reduce incidence of vaccine preventable disease1, 7, 8, 9, 10. Incidence of measles, mumps1, pertussis (whooping cough)9, and hepatitis A are lower in states with school entry requirements10.
Vaccine requirements for school attendance appear to increase completion of the hepatitis A vaccine series10, hepatitis B11, 12, and varicella vaccine13. Requirements also increase vaccination in adolescent populations8, 14, including hepatitis B11, 12, 15, 16, MMR15, 16, and TDaP booster vaccinations9. Requirements for some vaccines may also have spillover effects, potentially increasing uptake of other, non-required vaccines such as human papillomavirus (HPV)17 or meningococcal (MCV)9. HPV vaccine school entry requirements may increase HPV vaccination, though how they are structured and implemented (e.g., applying to all children rather than only girls) can impact effectiveness17.
Studies in the late 1970s of efforts to control measles transmission suggest that strict enforcement of school vaccine requirement laws (by excluding students without documented immunity via vaccination or previous infection) significantly decreases disease incidence18, 19, with the lowest incidence rates in states where laws covered all students in school, and not just those attending for the first time18.
Attitudes towards vaccines. Americans broadly support vaccine requirements for school attendance20, 21, particularly for MMR, DTaP, polio, and chickenpox20; support for the HPV vaccine has historically been weaker21. Most parents (76.6%-81%) support vaccine requirements to attend school22, 23. However, vaccine hesitancy has been increasing24, recently ranging from 6-25% of parents experiencing hesitancy around routinely administered vaccines25.
Exemptions. Nonmedical exemptions (NMEs), inconsistent enforcement of requirements, and clustering of families who under-immunize or choose not to vaccinate can all make school vaccination requirements less effective1. Medical exemptions to vaccine requirements have largely remained stable26. However, rates of NMEs have been steadily rising27, 28, 29, particularly in states introducing or allowing philosophical or personal belief exemptions24, and accelerating since the COVID-19 pandemic26.
Growing numbers of NMEs are associated with decreasing levels of MMR vaccination30, 31, 32, which increases the risk of preventable disease outbreaks32 and increases the risk of acquiring or transmitting vaccine preventable diseases such as pertussis and measles27, 33, 34, 35, 36. The children of parents who refuse vaccination are at the highest risk of infection37, 38. In the 2024-2025 school year, national estimates of MMR coverage were at 92.5%, below the 95% coverage needed for herd immunity during an outbreak31.
In states in which obtaining NMEs is easier, the number of NMEs27 and the annual increase in NMEs is higher than in states where the process is harder29. States with philosophical exemptions have higher rates of NMEs than those with only religious exemptions39. NMEs tend to occur in geographic or social clusters, with higher rates of exemptions in certain areas27. Clusters of vaccine exemptions are associated with increased local risk of vaccine preventable diseases24, 28.
Efforts to reduce or eliminate NMEs. States that have eliminated NMEs appear to have increasing levels of MMR coverage30. Overall, elimination of one or more types of NMEs appears to decrease exemptions40, 41, 42, 43, 44, 45. In most cases, this decrease is accompanied by an increase in medical exemptions40, 42, 43, 44, 45; however, implementation in New York featured a decrease in medical exemptions, possibly due to more rigorous requirements in the New York law41. Elimination of NMEs sometimes results in clustering, with some kindergartens having higher than average rates of medical exemptions40, or as in California, where the largest increases in NMEs clustered in counties that already had high levels of NMEs43, 44.
Stricter requirements may lower rates of NMEs, increase vaccination, and decrease the risk of vaccine-preventable outbreaks27. Stricter requirements for NMEs can include requiring more frequent applications for exemptions, adding steps to the process, and ensuring both monitoring and enforcement1. A California-based study (prior to its elimination of NMEs) suggests that requiring a medical provider’s signature to obtain an NME may decrease personal belief exemptions but not eliminate them46. A Michigan-based study suggests that requiring education sessions at the public health department may decrease NMEs in the first year; however, rates continue to increase in following years47. Outbreaks themselves may increase vaccination, as seeing the effects of a disease may impact perceived risk and awareness of a disease’s impacts48
While children who received some but not all recommended vaccinations are often from minoritized groups or families with lower incomes or less education, unvaccinated children are more likely to be white, come from higher income households, and have college educated mothers27, 28, 47. Private schools often have higher levels of both medical and nonmedical exemptions29.
Outbreaks of vaccine preventable diseases can be quite costly. On average, each measles case in an outbreak costs approximately $43,200, which rises to $58,600 when including the costs of public health response49.
How could this strategy advance health equity? This strategy is rated potential to decrease disparities: suggested by intervention design.
Vaccine requirements for K-12 schools have the potential to decrease disparities in vaccination for children from racially minoritized groups or from communities with low incomes1.
Available evidence is limited. A Chicago-based study suggests that a school entry requirement for hepatitis B can decrease vaccine coverage disparities for populations that are Black and Hispanic55. The initial implementation of an HPV mandate in Virginia and Washington, D.C. may have increased vaccination in populations that are low income or Black, but may have lowered HPV vaccination overall56; however, another study found no impact on uptake or disparities57. In an older study, rates of vaccination for hepatitis B were lower in schools with students from communities with lower incomes, regardless of requirements11. Experts suggest more comprehensive interventions may be needed as vaccination gaps persist, despite many years of interventions58.
Vaccine coverage varies by race, income, health insurance status, and geography59. Children from families with low incomes59, 60 and those from rural areas have lower vaccination rates than their counterparts59, and children and adolescents without health insurance have lower vaccination rates than those with Medicaid or private insurance59, 61. Barriers for parents with low incomes include out-of-pocket-costs, insufficient time off work to bring children to vaccination sites, with additional burdens for rural residents, who often need to travel significant distances to reach a provider59.
Disparities increased during the COVID-19 pandemic, with vaccine coverage rates dropping 5% for children in rural areas and for children whose families earned below the poverty level59. Among children who were infants during the pandemic, disparities in vaccination are more likely for those from households with lower incomes, for those on Medicaid or without insurance, those whose mothers did not complete high school62, and those who are Black, Hispanic, or American Indian and Alaskan Native children59; coverage disparities between states have widened since 202031.
What is the relevant historical background?
The invention of vaccines fundamentally changed humans’ relationship to disease and epidemic mortality. Most reportable vaccine preventable diseases have declined by 99% or more since the introduction of their vaccine18. In the years directly preceding the measles and polio vaccines, over half a million children contracted measles and more than 16,000 cases and nearly 1,900 deaths from paralytic polio were reported every year63.
In 1827, Boston became the first city to require smallpox vaccination for school attendance4, and in 1855, Massachusetts was the first state to enact school vaccine requirements to prevent smallpox transmission4. Local and state laws evolved as more vaccines were created, incorporating diphtheria in the 1930s and polio and measles in the 1960s4. By the early 1980s, every state had laws requiring vaccines for students first entering school18. At the beginning of the 21st century, vaccine coverage for 19 to 36-month-olds was at an all-time high18, and fewer than 1% of students had an exemption of any kind to school entry requirements18. However, growing concerns over vaccine safety, fueled by a now discredited and retracted study64, led more parents to delay vaccination, follow alternate immunization schedules, or refuse vaccinations completely24, 27.
Resistance to school vaccination laws first arose in the late 1800s, driven then as now by safety concerns and protests against government overreach4. Campaigns against state laws led Massachusetts to allow the first “medical exemptions” in 1894, while requirements were repealed in Washington in 1919 and Wisconsin in 1920; Utah and North Dakota later passed laws forbidding compulsory vaccination4. In 1922, the Supreme Court ruled in Zucht v. King that childhood vaccination requirements were constitutional18. Anti-vaccine activism decreased during the following decades, particularly if exemptions were available4. However, anti-vaccine activism reemerged in the 1980s around the safety of the pertussis vaccine and has continued4.
Anti-vaccine rhetoric is far more common today than in the era when many vaccine requirements were passed; new requirements will likely face even greater push back8 as views on vaccine requirements become increasingly partisan65. Misleading claims about vaccines by Department of Health and Human Services (HHS) Secretary Robert F. Kennedy, Jr. and other political figures have added to parents’ confusion and uncertainty about vaccines66. The federal government revised the childhood vaccine schedule in January 2026 (significantly reducing the number of recommended vaccines), weakened universal vaccine requirements, and eliminated or reduced funding for research into vaccines, vaccine promotion, and vaccine hesitancy67. While a federal judge has temporarily blocked the revised vaccine schedule, the Trump administration issued an executive order in August 2026, again reducing routine vaccinations (from 13 to 7) and diseases targeted (from 17 to 11)68.
Despite efforts to end vaccine requirements and increase exemptions, a majority of parents from across the political spectrum support laws that require children to be vaccinated against diseases such as polio and the measles to attend school22, as do most Americans, although partisan affiliation appears to more deeply impact approval of vaccines for COVID-19 and HPV20. As of August 2026, 26 states and Washington D.C. rely on sources other than the federal government for childhood vaccine recommendations69.
Equity Considerations
- How can you advocate to maintain or increase vaccine requirements for your community? Who can you partner with in such efforts?
- Who benefits from the repeal of vaccine requirements? Who is hurt by them?
Implementation Examples
During the 2025-2026 school year, vaccination coverage once again decreased among entering kindergarteners for all reported vaccines (from 92.4% to 92%), and exemptions increased to 4.2%; 24 states had exemption rates greater than 5%50. More than half of states experienced decreases in coverage for MMR, DTaP, polio, and varicella vaccines50. Coverage remains near universal in Connecticut, Maine, Mississippi, New York, and West Virginia, while Alaska, Florida, Idaho, Minnesota, and Wisconsin are 8-15% lower31.
As of September 2026, all 50 states and Washington, D.C. require some form of immunization before school entry, and every state allows medical exemptions for children unable to receive vaccines for medical reasons51. Nonmedical exemptions (NMEs) are available in many states: 30 states and Washington, D.C. allow religious exemptions, 15 states allow personal and religious exemptions, and Minnesota state law allows for personal belief exemptions2, 51. California, Connecticut, Maine, and New York have eliminated NMEs26.
As of August 2026, 27 states no longer use the Centers for Disease Control (CDC)/Advisory Committee on Immunization Practices (ACIP) as their source for vaccine recommendations2. For example, Colorado’s state board of health now determines the list of vaccines required for school entry52.
Attempts by the Florida Surgeon General to eliminate all vaccine requirements for public schools resulted in the elimination of four vaccine requirements and the expansion of religious exemptions; vaccines for specific diseases required by Florida state law (measles, mumps, and rubella (MMR), polio, diphtheria, rubeola, and tetanus) will still be required53.
The National Conference of State Legislatures’ State Public Health Legislation Database identified 91 bills introduced in 30 state legislatures regarding vaccine requirements, as of October 202654.
Implementation Resources
‡ Resources with a focus on equity.
Immunize-Requirements - Immunize.Org. (2026, June 30). State vaccine-specific requirements. Retrieved October 20, 2026.
Immunize-Exemptions - Immunize.Org. (2026, June 30). School and Childcare Immunization Exemption Policies. Retrieved October 22, 2026.
Immunize-Risks - Immunize.org. (2024). Non-medical exemptions and vaccine refusal put people at risk. Examine the evidence for yourself (No. P2069). Retrieved October 21, 2026.
CDC-SchoolVaxView Resources - Centers for Disease Control and Prevention (CDC). (2026, August 14). Publications and Resources. SchoolVaxView. Retrieved October 21, 2026.
NCSL-State NMEs - National Conference of State Legislatures (NCSL). (n.d.). State non-medical exemptions from school immunization requirements. Retrieved October 20, 2026.
NCSL-PH legislation - National Conference of State Legislatures (NCSL). (n.d.). State public health legislation database. Retrieved October 20, 2026.
Footnotes
* Journal subscription may be required for access.
1 CG-Vaccination - The Guide to Community Preventive Services (The Community Guide). Vaccination: School, college requirements.
2 KFF-Michaud 2026 - Michaud, J., Bell, C., & Kates, J. (2026, August 21). State and local policies on school vaccine requirements: Overview and current status. KFF. Retrieved October 21, 2026.
3 Immunize-Requirements - Immunize.Org. (2026, June 30). State vaccine-specific requirements. Retrieved October 20, 2026.
4 Diekema 2014 - Diekema, D. S. (2014). Personal belief exemptions from school vaccination requirements. Annual Review of Public Health, 35(1), 275–292.
5 CDC-PHLP vaccination - Public Health Law Project (PHLP). (2022). State school immunization requirements and vaccine exemption laws. Center for State, Tribal, Local, and Territorial Support. Centers for Disease Control and Prevention (CDC). Retrieved October 21, 2026.
6 Dudley 2020 - Dudley, M. Z., Halsey, N. A., Omer, S. B., Orenstein, W. A., O’Leary, S. T., Limaye, R. J., & Salmon, D. A. (2020). The state of vaccine safety science: Systematic reviews of the evidence. The Lancet Infectious Diseases, 20(5), e80–e89.
7 Kuznetsova 2021 - Kuznetsova, L., Cortassa, G., & Trilla, A. (2021). Effectiveness of mandatory and incentive-based routine childhood immunization programs in Europe: A systematic review of the literature. Vaccines, 9(10), 1173.
8 Lee 2016d - Lee, C., & Robinson, J. L. (2016). Systematic review of the effect of immunization mandates on uptake of routine childhood immunizations. Journal of Infection, 72(6), 659–666.
9 Carpenter 2019 - Carpenter, C. S., & Lawler, E. C. (2019). Direct and spillover effects of middle school vaccination requirements. American Economic Journal: Economic Policy, 11(1), 95–125.
10 Lawler 2017 - Lawler, E. C. (2017). Effectiveness of vaccination recommendations versus mandates: Evidence from the hepatitis A vaccine. Journal of Health Economics, 52, 45–62.
11 Wilson 2005a - Wilson, T. R., Fishbein, D. B., Ellis, P. A., & Edlavitch, S. A. (2005). The impact of a school entry law on adolescent immunization rates. Journal of Adolescent Health, 37(6), 511–516.
12 Jacobs 2004a - Jacobs, R., & Meyerhoff, A. (2004). Effect of middle school entry requirements on hepatitis B vaccination coverage. Journal of Adolescent Health, 34(5), 420–423.
13 Abrevaya 2011 - Abrevaya, J., & Mulligan, K. (2011). Effectiveness of state-level vaccination mandates: Evidence from the varicella vaccine. Journal of Health Economics, 30(5), 966–976.
14 Das 2016a - Das, J. K., Salam, R. A., Arshad, A., Lassi, Z. S., & Bhutta, Z. A. (2016). Systematic review and meta-analysis of interventions to improve access and coverage of adolescent immunizations. Journal of Adolescent Health, 59(4), S40–S48.
15 Averhoff 2004 - Averhoff, F., Linton, L., Peddecord, K. M., Edwards, C., Wang, W., & Fishbein, D. (2004). A middle school immunization law rapidly and substantially increases immunization coverage among adolescents. American Journal of Public Health, 94(6), 978–984.
16 Rickert 2004 - Rickert, D., Deladisma, A., Yusuf, H., Averhoff, F., Brink, E., & Shih, S. (2004). Adolescent immunizations: Are we ready for a new wave? American Journal of Preventive Medicine, 26(1), 22–28.
17 McKeithen 2024 - McKeithen, M. C., Gilkey, M. B., Kong, W. Y., Oh, N. L., Heisler-MacKinnon, J., Carlson, R., James, G., & Grabert, B. K. (2024). Policy approaches for increasing adolescent HPV vaccination coverage: A systematic review. Pediatrics, 153(5), e2023064692.
18 Malone 2003 - Malone, K. M., & Hinman, A. R. (2003). Vaccination mandates: The public health imperative and individual rights. In R. A. Goodman, M. Rothstein, R. E. Hoffman, W. Lopez, G. W. Matthews, & K. Foster (Eds.), Law in Public Health Practice (1st ed., pp. 262–284). Oxford University Press: New York.
19 CDC MMWR 1982 - Epidemiologic notes and reports school immunization requirements for measles—United States, 1982. (1982). MMWR. Morbidity and Mortality Weekly Report, 31(6), 65–67.
20 Haeder 2023 - Haeder, S. F. (2023). U.S. public support and opposition to vaccination mandates in K-12 education in light of the COVID-19 pandemic. Vaccine, 41(48), 7103–7115.
21 Gualano 2019 - Gualano, M., Olivero, E., Voglino, G., Corezzi, M., Rossello, P., Vicentini, C., Bert, F., & Siliquini, R. (2019). Knowledge, attitudes and beliefs towards compulsory vaccination: A systematic review. Human Vaccines & Immunotherapeutics, 15(4), 918–931.
22 KFF-Kearney 2025 - Kearney, A. (2025, September 4). Most parents nationally and in Florida want schools to require vaccines. KFF. Retrieved October 21, 2026.
23 CDC-Calhoun 2024 - Calhoun, K., Zhou, T., Dramann, D., & Seither, R. (2025, December 16). Parental attitudes and behaviors toward school and daycare vaccination requirements. SchoolVaxView. Centers for Disease Control and Prevention (CDC). Retrieved October 21, 2026.
24 Sadaf 2013 - Sadaf, A., Richards, J. L., Glanz, J., Salmon, D. A., & Omer, S. B. (2013). A systematic review of interventions for reducing parental vaccine refusal and vaccine hesitancy. Vaccine, 31(40), 4293–4304.
25 Nowak 2023 - Nowak, G. J., & Cacciatore, M. A. (2023). State of vaccine hesitancy in the United States. Pediatric Clinics of North America, 70(2), 197–210.
26 Fattah 2026 - Fattah, M., Stoffel, L. A., Bubar, K. M., Bents, S. J., Maldonado, Y., Hotez, P. J., Kiang, M. V., & Lo, N. C. (2026). Trends in county-level childhood vaccination exemptions in the U.S. JAMA, 335(6), 546–549.
27 Wang 2014a - Wang, E., Clymer, J., Davis-Hayes, C., & Buttenheim, A. (2014). Nonmedical exemptions from school immunization requirements: A systematic review. American Journal of Public Health, 104(11), e62–e84.
28 Omer 2009 - Omer, S. B., & Orenstein, W. A. (2009). Vaccine refusal, mandatory immunization, and the risks of vaccine-preventable diseases. The New England Journal of Medicine, 360(19), 1981–1989.
29 Bednarczyk 2019 - Bednarczyk, R. A., King, A. R., Lahijani, A., & Omer, S. B. (2019). Current landscape of nonmedical vaccination exemptions in the United States: Impact of policy changes. Expert Review of Vaccines, 18(2), 175–190.
30 Saiyed 2025 - Saiyed, S., Dong, E., & Gardner, L. M. (2025). The relationship between state vaccination exemption policies and MMR vaccination trends in the U.S. Vaccine, 64, 127773.
31 Hijano 2026 - Hijano, D. R. (2026). Non-medical exemptions and state-level variation in kindergarten MMR vaccination coverage, United States, 2016–2024. Frontiers in Public Health, 14, 1795927.
32 CDC MMWR-Seither 2024 - Seither, R., Yusuf, O. B., Dramann, D., Calhoun, K., Mugerwa-Kasujja, A., Knighton, C. L., Kriss, J. L. Miller, R.,& Peacock, G. (2024). Coverage with selected vaccines and exemption rates among children in kindergarten—United States, 2023–24 school year. MMWR. Morbidity and Mortality Weekly Report, 73(41), 925–932.
33 Omer 2006 - Omer, S. B., Pan, W. K. Y., Halsey, N. A., Stokley, S., Moulton, L. H., Navar, A. M., Pierce, M., & Salmon, D. A. (2006). Nonmedical exemptions to school immunization requirements: Secular trends and association of state policies with pertussis incidence. JAMA, 296(14), 1757–1763.
34 Feikin 2000 - Feikin, D. R., Lezotte, D. C., Hamman, R. F., Salmon, D. A., Chen, R. T., & Hoffman, R. E. (2000). Individual and community risks of measles and pertussis associated with personal exemptions to immunization. JAMA, 284(24), 3145.
35 Imdad 2013 - Imdad, A., Tserenpuntsag, B., Blog, D. S., Halsey, N. A., Easton, D. E., & Shaw, J. (2013). Religious exemptions for immunization and risk of pertussis in New York State, 2000–2011. Pediatrics, 132(1), 37–43.
36 Salmon 1999 - Salmon, D. A., Haber, M., Gangarosa, E. J., Phillips, L., Smith, N. J., & Chen, R. T. (1999). Health consequences of religious and philosophical exemptions from immunization laws: Individual and societal risk of measles. JAMA, 282(1), 47.
37 Glanz 2010 - Glanz, J. M., McClure, D. L., Magid, D. J., Daley, M. F., France, E. K., & Hambidge, S. J. (2010). Parental refusal of varicella vaccination and the associated risk of varicella infection in children. Archives of Pediatrics & Adolescent Medicine, 164(1).
38 Glanz 2009 - Glanz, J. M., McClure, D. L., Magid, D. J., Daley, M. F., France, E. K., Salmon, D. A., & Hambidge, S. J. (2009). Parental refusal of pertussis vaccination is associated with an increased risk of pertussis infection in children. Pediatrics, 123(6), 1446–1451.
39 Omer 2012 - Omer, S. B., Richards, J. L., Ward, M., & Bednarczyk, R. A. (2012). Vaccination policies and rates of exemption from immunization, 2005–2011. New England Journal of Medicine, 367(12), 1170–1171.
40 Gromis 2026 - Gromis, A., & Faherty, L. J. (2026). School-entry vaccine exemptions in Maine before and after public law 154, 2018–2023. Vaccine, 71, 128103.
41 Correira 2024 - Correira, J. W., Kamstra, R., Zhu, N., & Doll, M. K. (2024). School vaccine coverage and medical exemption uptake after the New York State repeal of nonmedical vaccination exemptions. JAMA Network Open, 7(2), e2354710.
42 Moore 2024a - Moore, T., Graff, K., & Bell, T. R. (2024). Characteristics associated with measles, mumps, and rubella coverage and exemptions after a school immunization law change in Washington, 2019‐2020. Journal of School Health, 94(11), 1031–1039.
43 NBER-Richwine 2019 - Richwine, C., Dor, A., & Moghtaderi, A. (2019). Do stricter immunization laws improve coverage? Evidence from the repeal of non-medical exemptions for school mandated vaccines (No. W25847; p. w25847). National Bureau of Economic Research (NBER). Retrieved October 21, 2026.
44 Nyathi 2019 - Nyathi, S., Karpel, H. C., Sainani, K. L., Maldonado, Y., Hotez, P. J., Bendavid, E., & Lo, N. C. (2019). The 2016 California policy to eliminate nonmedical vaccine exemptions and changes in vaccine coverage: An empirical policy analysis. PLOS Medicine, 16(12), e1002994.
45 Delamater 2017 - Delamater, P. L., Leslie, T. F., & Yang, Y. T. (2017). Change in medical exemptions from immunization in California after elimination of personal belief exemptions. JAMA, 318(9), 863.
46 Buttenheim 2018 - Buttenheim, A. M., Jones, M., Mckown, C., Salmon, D., & Omer, S. B. (2018). Conditional admission, religious exemption type, and nonmedical vaccine exemptions in California before and after a state policy change. Vaccine, 36(26), 3789–3793.
47 Masters 2021 - Masters, N. B., Zelner, J., Delamater, P. L., Hutton, D., Kay, M., Eisenberg, M. C., & Boulton, M. L. (2021). Evaluating Michigan’s administrative rule change on nonmedical vaccine exemptions. Pediatrics, 148(3), e2021049942.
48 NBER-Oster 2016 - Oster, E. (2016). Does disease cause vaccination? Disease outbreaks and vaccination response (No. W22464). National Bureau of Economic Research (NBER). Retrieved October 21, 2026.
49 Sriudomporn 2026 - Sriudomporn, S., & Patenaude, B. (2026). Quantifying the cost of measles outbreaks in the U.S. and how costs scale with outbreak size. Vaccine, 91, 129040.
50 CDC-SchoolVaxView - Centers for Disease Control and Prevention (CDC). (2026, August 14). Vaccination coverage and exemptions among kindergartners. SchoolVaxView. Retrieved October 21, 2026.
51 NCSL-State NMEs - National Conference of State Legislatures (NCSL). (n.d.). State non-medical exemptions from school immunization requirements. Retrieved October 20, 2026.
52 ASTHO-Nair 2026 - Nair, S., Martin, K., & Baker-White, A. (2026, August 10). How states are expanding immunization access through policy. Association of State and Territorial Health Officials (ASTHO). Retrieved October 21, 2026.
53 CIDRAP-Soucheray 2026 - Soucheray, S. (2026, August 4). Florida’s department of health removes 4 vaccines from required list for public schools. Center for Infectious Disease Research and Policy (CIDRAP). Retrieved October 22, 2026.
54 NCSL-PH legislation - National Conference of State Legislatures (NCSL). (n.d.). State public health legislation database. Retrieved October 20, 2026.
55 Morita 2008 - Morita, J. Y., Ramirez, E., & Trick, W. E. (2008). Effect of a school-entry vaccination requirement on racial and ethnic disparities in hepatitis B immunization coverage levels among public school students. Pediatrics, 121(3), e547–e552.
56 Polonijo 2020 - Polonijo, A. N. (2020). The impact of school-entry mandates on social inequalities in human papillomavirus vaccination. SSM - Population Health, 12, 100647.
57 Cuff 2016 - Cuff, R. D., Buchanan, T., Pelkofski, E., Korte, J., Modesitt, S. P., & Pierce, J. Y. (2016). Rates of human papillomavirus vaccine uptake amongst girls five years after introduction of statewide mandate in Virginia. American Journal of Obstetrics and Gynecology, 214(6), 752.e1-752.e6.
58 Brumbaugh 2024 - Brumbaugh, K. Q., Ornelas, I. J., Casas, F. R., & Mokdad, A. H. (2024). Achieving equity in childhood vaccination: A mixed-methods study of immunization programs, policies, and coverage in 3 US states. Journal of Public Health Management & Practice, 30(1), E31–E40.
59 NCSL-Kolman 2024 - Kolman, S., & Meyer, C. (2024, February 29). Routine child vaccination rates lower than pre-pandemic levels. National Conference of State Legislatures (NCSL). Retrieved October 21, 2026.
60 CWF-Crays 2026 - Crays, A., Farrell, C., & Musumeci, M. (2026, January 29). Kids lose when federal vaccine coverage rules are unclear—Understanding the recent changes in federal vaccine guidance. The Commonwealth Fund (CWF). Retrieved October 21, 2026.
61 Lu 2018 - Lu, P., Yankey, D., Jeyarajah, J., O’Halloran, A., Fredua, B., Elam-Evans, L. D., & Reagan-Steiner, S. (2018). Association of health insurance status and vaccination coverage among adolescents 13-17 years of age. The Journal of Pediatrics, 195, 256-262.e1.
62 Lv 2025 - Lv, X., Long, A., Chen, Y., & Fang, H. (2025). Socioeconomic disparities in childhood vaccination coverage in the United States: Evidence from a post-COVID-19 birth cohort. Vaccines, 13(12), 1256.
63 CDC MMWR-National Immunization Program 1999 - National Immunization Program. (1999). Achievements in public health, 1900-1999 impact of vaccines universally recommended for children -- United States, 1990-1998. Morbidity and Mortality Weekly Report (MMWR), 48(12), 243—248. Accessed June 2, 2026.
64 IVS-Autism 2025 - Institute for Vaccine Safety (IVS). (2025, May 19). Do vaccines cause autism? Johns Hopkins Bloomberg School of Public Health. Accessed May 26, 2026.
65 KFF-Williams 2025 - Williams, E., Kates, J., & Michaud, J. (2025). Kindergarten routine vaccination rates continue to decline. KFF. Accessed June 4, 2026.
66 KFF-Washington 2025 - Washington, I., Yilma, H., & Luther, J. (2025, September 25). New KFF-Washington Post poll explores parents’ vaccine attitudes, and confusion follows ACIP meeting on vaccine recommendations. KFF’s Health Information and Trust Initiative: The Monitor, 31. Accessed May 26, 2026.
67 Motta 2026 - Motta, M., Callaghan, T., Ulrich, M. R., McCuskey, E. Y., & Huberfeld, N. (2026, March 3). Attacks on vaccine hesitancy and promotion research undermine public health. Health Affairs Forefront.
68 KFF-Michaud 2026a - Mihaud, J., & Kates, J. (2026, August 11). The White House takes another shot at changing U.S. childhood vaccine recommendations. KFF. Retrieved October 21, 2026.
69 KFF-State vaccine rec sources - KFF. (n.d.). Reliance on sources other than CDC/ACIP for state childhood vaccine recommendations | KFF State Health Facts. Retrieved October 21, 2026.
Related What Works for Health Strategies
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