Effectiveness of state-level vaccination mandates: evidence from the varicella vaccine

School-Entry Vaccine Policies: States' Responses To Federal Recommendations Varied From Swift To Substantially Delayed

School-entry immunization requirements are a valuable strategy to reduce the spread of vaccine-preventable diseases. This research examined the temporal relationship between recommendations issued by the federal Advisory Committee on Immunization Practices (ACIP) and corresponding school-entry requirements adopted by states for adolescent meningococcal ACWY (MenACWY) and tetanus, diphtheria, and acellular pertussis (Tdap) vaccines. A legal epidemiological review of statutes, regulations, and state agency guidance identified school-entry policies across fifty states and Washington, D.C. Researchers measured the number of months between the date of an ACIP recommendation and the effective dates for state policies that were in place through the 2023-24 school year. All fifty-one jurisdictions had school-entry requirement policies for Tdap vaccination, and thirty-six had school-entry requirements for MenACWY vaccination. The average period between ACIP's recommendations and state policy adoption was 4.94, 9.61, and 8.24 years for Tdap and for MenACWY first and booster doses, respectively. This analysis found diverse timelines and notable delays for both Tdap and MenACWY school-entry requirement policies. This heterogeneity and patchwork of state requirements underscores the need for ACIP to evaluate the role of these policies in reducing vaccine-preventable diseases across the United States.

Vaccine-skeptic physicians and patient vaccination decisions

What is the role of general practitioners (GPs) in supporting or hindering public health efforts? We investigate the influence of vaccine-skeptic GPs on their patients' decisions to get a COVID-19 vaccination. We identify vaccine-skeptic GPs from the signatories of an open letter in which 199 Austrian physicians expressed their skepticism about COVID-19 vaccines. We examine small rural municipalities where patients choose a GP primarily based on geographic proximity. These vaccine-skeptic GPs reduced the vaccination rate by 5.6 percentage points. This estimate implies that they discouraged 7.9% of the vaccinable population. The effect appears to stem from discouragement rather than rationing vaccine access.

Reminder design and childhood vaccination coverage

A major policy concern across public vaccination programs is non-compliance. Exploiting Danish population data and three national reforms in regression discontinuity designs, we document the effects of reminders for childhood vaccination coverage. Retrospective reminders are primarily effective for families with small children and when sent out close to the recommended vaccination age. Digital and postal reminders are equally effective. Prospective reminders increase timely vaccinations in later childhood and help reaching high coverage for new vaccines in increasingly complex vaccination programs. While reminders prompt additional preventive care for focal children, we find no spillovers to other health behaviors or relatives.

Impact of a hypothetical COVID-19 vaccine mandate on parental likelihood to vaccinate children: Exploring school-related concerns and vaccination decision-making

OBJECTIVE

We assessed the impact of a hypothetical school-entry COVID-19 vaccine mandate on parental likelihood to vaccinate their child.

METHODS

We collected demographics, COVID-19-related school concerns, and parental likelihood to vaccinate their child from parents of patients aged 3-16 years seen across nine pediatric Emergency Departments from 06/07/2021 to 08/13/2021. Wilcoxon signed-rank test compared pre- and post-mandate vaccination likelihood. Multivariate linear and logistic regression analyses explored associations between parental concerns with baseline and change in vaccination likelihood, respectively.

RESULTS

Vaccination likelihood increased from 43% to 50% with a hypothetical vaccine mandate (Z = -6.69, p < 0.001), although most parents (63%) had no change, while 26% increased and 11% decreased their vaccination likelihood. Parent concerns about their child contracting COVID-19 was associated with greater baseline vaccination likelihood. No single school-related concern explained the increased vaccination likelihood with a mandate.

CONCLUSION

Parental school-related concerns did not drive changes in likelihood to vaccinate with a mandate.

Direct and crowding-out effects of a Hepatitis B vaccination campaign

We evaluate the direct and spillover causal effects of a Hepatitis B (HB) vaccination campaign in French schools on the vaccination adherence of the targeted pupils. Using a regression discontinuity design, we show that this campaign created an exogenous shock on vaccination behavior, increasing the HB vaccination rate for children aged 11 and above. At the same time, we show a drop in the measles, mumps, and rubella (MMR) vaccination rate of the targeted pupils and an increase in the parental belief that measles is a benign disease. We interpret these results as a salience effect: the focus on HB vaccination leads to a decrease in the belief that other vaccines are as important. The effect on MMR vaccination was relatively unexpected and may imply a negative externality. Measles is an extremely contagious disease. If the vaccination rate falls, the disease will spread further, raising the question of the net effect of the HB vaccination campaign on the well-being of the population.

EXPERTISE, DISAGREEMENT, and TRUST IN VACCINE SCIENCE AND POLICY. The importance of transparency in a world of experts

We discuss the relationship between expertise, expert authority, and trust in the case of vaccine research and policy, with a particular focus on COVID-19 vaccines. We argue that expert authority is not merely an epistemic notion, but entails being trusted by the relevant public and is valuable if it is accompanied by expert trustworthiness. Trustworthiness requires, among other things, being transparent, acknowledging uncertainty and expert disagreement (e.g., around vaccines' effectiveness and safety), being willing to revise views in response to new evidence, and being clear about the values that underpin expert recommendations. We explore how failure to acknowledge expert disagreement and uncertainty can undermine trust in vaccination and public health experts, using expert recommendations around COVID-19 vaccines as a case study.

Internal and external factors affecting vaccination coverage: Modeling the interactions between vaccine hesitancy, accessibility, and mandates

Society, culture, and individual motivations affect human decisions regarding their health behaviors and preventative care, and health-related perceptions and behaviors can change at the population level as cultures evolve. An increase in vaccine hesitancy, an individual mindset informed within a cultural context, has resulted in a decrease in vaccination coverage and an increase in vaccine-preventable disease (VPD) outbreaks, particularly in developed countries where vaccination rates are generally high. Understanding local vaccination cultures, which evolve through an interaction between beliefs and behaviors and are influenced by the broader cultural landscape, is critical to fostering public health. Vaccine mandates and vaccine inaccessibility are two external factors that interact with individual beliefs to affect vaccine-related behaviors. To better understand the population dynamics of vaccine hesitancy, it is important to study how these external factors could shape a population's vaccination decisions and affect the broader health culture. Using a mathematical model of cultural evolution, we explore the effects of vaccine mandates, vaccine inaccessibility, and varying cultural selection trajectories on a population's level of vaccine hesitancy and vaccination behavior. We show that vaccine mandates can lead to a phenomenon in which high vaccine hesitancy co-occurs with high vaccination coverage, and that high vaccine confidence can be maintained even in areas where access to vaccines is limited.

Between nudges and mandates: The drivers of COVID-19 vaccination intentions and subsequent uptake in Russia

Despite high levels of morbidity and mortality, as well as the widespread availability of domestic vaccines, Russia demonstrated significantly low rates of vaccination throughout the COVID-19 pandemic. This research explores vaccination intentions before the start of the immunisation campaign and the consequent uptake in Russia after the introduction of mandatory vaccination policy in certain industries and proof-of-immunisation for social activities. Using a nationally representative panel dataset, we analyse factors behind individual vaccination decisions using binary and multinomial logistic regressions. Special attention is given to the effect of employment in industries with vaccine mandates and personal factors which determine individual "nudgeability" to vaccination (e.g., personality traits, beliefs, vaccine alertness, self-perceived vaccine availability etc.). Our results show that 49 per cent of the population received at least one shot of COVID-19 vaccine by autumn 2021 after the introduction of mandatory vaccination. Vaccination intentions before the rollout of the nationwide immunisation campaign are correlated with the consequent attitudes and uptake, although the prediction is not perfect. 40 percent of vaccine refusers eventually got vaccinated, while 16 percent of vaccine supporters turned into refusers, revealing the lack of promotion of vaccine safety and effectiveness. To a large extent, vaccination refusal and hesitance are explained by vaccine alertness. Vaccine mandates significantly increased the uptake in several affected industries, especially education. These results offer important insights for designing information policy, relevant for future vaccination campaigns.

How do COVID-19 vaccine mandates affect attitudes toward the vaccine and participation in mandate-affected activities? Evidence from the United States

The spread of COVID-19 has prompted many governments, schools, and companies to institute vaccine mandates. Proponents suggest that mandates will enhance public health and increase vaccination rates. Critics suggest that evidence of mandates' effectiveness is unclear and warn that mandates risk increasing societal inequalities if unvaccinated minority groups opt out of educational, commercial, and social activities where mandates are required. We conduct an original survey experiment on a nationally representative sample of 1,245 Americans to examine the efficacy and effect of COVID-19 mandates. Our findings suggest that mandates are unlikely to change vaccination behavior overall. Further, they may increase the likelihood that sizable percentages of the population opt out of activities where vaccines are mandated. We conclude that mandates that do go into effect should be accompanied by persuasive communications targeted to specific information needs and identities.

Reminders of existing vaccine mandates increase support for a COVID-19 vaccine mandate: Evidence from a survey experiment

BACKGROUND

Governments are trying various strategies to boost COVID-19 vaccination rates, including vaccine mandates. Popular support for such mandates, however, is in flux in many countries, including the United States. The objective of this study is to evaluate if the wording of public health messages could increase popular support for COVID-19 vaccine mandates.

METHODS

We conducted a survey experiment on a sample of 573 registered voters in South Dakota, United States. Participants in the control group (n = 271) read a short message about mandatory COVID-19 vaccination. Respondents in the treatment group (n = 278) read the same message but they were reminded that a variety of vaccine mandates for measles, mumps, rubella, and polio have long been required. Afterwards, both groups were asked about their support for COVID-19 vaccine mandate.

RESULTS

A multivariate ordinary least squares regression analysis revealed that the experimental treatment had a positive and statistically significant impact on support for mandatory COVID-19 vaccination (p < 0.001). We also found that COVID-19 vaccination status, religious identity, and political affiliation have a statistically significant effect.

CONCLUSIONS

Our findings suggest that a simple intervention-reminding the public of the existing vaccine mandates-increases support for COVID-19 vaccine mandate. Public health authorities who seek to boost COVID-19 vaccination rates could utilize this approach.

COVID-19 Vaccines and the Virtues

From a moral point of view, what arguments are there for and against seeking COVID-19 vaccination? Can it be morally permissible to require (parts of) a population to receive a vaccine? The present paper adopts a perspective of virtue ethics and argues both that it is morally right for an individual virtuous moral agent to seek COVID-19 vaccination and for a virtuous ruler to impose mandatory vaccinations on her population. We begin by first presenting virtue ethics and the current vaccine controversy. Second, we examine whether a virtuous individual should get vaccinated. Third, we consider whether, from a moral point of view, it is right for a ruler to impose mandatory vaccinations on her citizens. Fourth, we answer some objections to our argument. Finally, we conclude that virtue ethical considerations warrant both the individual choice of getting vaccinated and mandatory vaccinations against COVID-19.

Association Between State-Issued COVID-19 Vaccine Mandates and Vaccine Administration Rates in 12 US States and the District of Columbia

Importance

Some US states have issued COVID-19 vaccine mandates; however, the association of these mandates with vaccination rates remains unknown.

Objective

To examine the association between announcing state-issued COVID-19 vaccine mandates that did not provide a test-out option for workers and the vaccine administration rates in terms of state-level first-dose vaccine administration and series completion coverage.

Design, Setting, and Participants

This cross-sectional study used publicly available, state-level aggregated panel data to fit linear regression models with 2-way fixed effects (state and time) estimating vaccine coverage changes 8 weeks before and 8 weeks after a state-issued COVID-19 vaccine mandate was announced. Mandates were announced on or after July 26, 2021, and were included only if they went into effect before December 31, 2021. Data were included from 13 state-level jurisdictions with a vaccine mandate in effect as of December 31, 2021, that did not allow recurring testing in lieu of vaccination (mandate group), and 14 state-level jurisdictions that allowed a test-out option and/or did not restrict vaccine requirements (comparison group).

Interventions/Exposures

The event of interest was the announcement of a state-issued COVID-19 vaccine mandate applicable to specific groups of workers.

Main Outcomes and Measures

The outcome measures were state-level daily COVID-19 vaccine first-dose administration and series completion coverage, reported as mean percentage point changes.

Results

Of 5 508 539 first-dose administrations in the 8-week postannouncement period, an estimated 634 831 (11.5%) were associated with the mandate announcement. First-dose administration coverage among 13 jurisdictions increased starting at 3 weeks after the mandate announcement, with statistically significant differences of 0.20, 0.33, 0.39, 0.45, 0.49, and 0.59 percentage points higher than the referent category coverage of 62.9%. Increases in vaccine series completion coverage were observed from 5 to 8 weeks after the announcement, but statistically significant differences from the referent category coverage of 56.3% were observed only during weeks 7 and 8 after the announcement (both differed by 0.2 percentage points; P = .05 and P = .02, respectively).

Conclusions and Relevance

The findings of this cross-sectional event study suggest that the announcement of state-issued vaccine mandates may be associated with short-term increases in vaccine uptake. This observed association may be a product of both a direct outcome experienced by groups governed by the mandate as well as the spillover outcome due to a government signaling the importance of vaccination to the general population of the state.

Conditional cash lotteries increase COVID-19 vaccination rates

Conditional cash lotteries (CCLs) provide people with opportunities to win monetary prizes only if they make specific behavioral changes. We conduct a case study of Ohio's Vax-A-Million initiative, the first CCL targeting COVID-19 vaccinations. Forming a synthetic control from other states, we find that Ohios incentive scheme increases the vaccinated share of state population by 1.5 percent (0.7 pp), costing sixty-eight dollars per person persuaded to vaccinate. We show this causes significant reductions in COVID-19, preventing at least one infection for every six vaccinations that the lottery had successfully encouraged. These findings are promising for similar CCL public health initiatives.

Factors affecting recommended childhood vaccine demand

Reaching a high vaccination coverage level is of vital essence when preventing epidemic diseases. For mandatory vaccines, the demand can be forecasted using some demographics such as birth rates or populations between certain ages. However, it has been difficult to forecast non-mandatory vaccine demands because of vaccine hesitation, alongside other factors such as social norms, literacy rate, or healthcare infrastructure. Consequently, the purpose of this study is to explore the predominant factors that affect the non-mandatory vaccine demand, focusing on the recommended childhood vaccines, which are usually excluded from national immunization programs. For this study, fifty-nine factors were determined and categorized as system-oriented and human-oriented factors. After a focus group study conducted with ten experts, seven system-oriented and eight human-oriented factors were determined. To reveal the cause and effect relationship between factors, one of the multi-criteria decision-making methods called Fuzzy-DEMATEL was implemented. The results of the analysis showed that “Immunization-related beliefs”, “Media/social media contents/messaging”, and “Social, cultural, religious norms” have a strong influence on non-mandatory childhood vaccine demand. Furthermore, whereas “Availability and access to health care facilities” and “Political/ financial support to health systems” are identified as cause group factors, “Quality of vaccine and service delivery management” is considered an effect group factor. Lastly, a guide was generated for decision-makers to help their forecasting process of non-mandatory vaccine demands to avoid vaccine waste or shortage.

Personal belief exemptions for school-entry vaccinations, vaccination rates, and academic achievement

Nonmedical exemptions from school-entry vaccine mandates are receiving increased policy and public health scrutiny. This paper examines how expanding the availability of exemptions influences vaccination rates in early childhood and academic achievement in middle school. We leverage 2003 legislation that granted personal belief exemptions (PBE) in Texas and Arkansas, two states that previously allowed exemptions only for medical or religious regions. We find that PBE decreased vaccination coverage among Black and low-income preschoolers by 16.1% and 8.3%, respectively. Furthermore, we find that those cohorts affected by the policy change in early childhood performed less well on standardized tests of academic achievement in middle school. Estimated effects on test scores were largest for Black students and economically disadvantaged students.

How important is the structure of school vaccine requirement opt-out provisions? Evidence from Washington, DC's HPV vaccine requirement

Recent increases in vaccine-preventable diseases have led policymakers to reconsider the scope of vaccine requirement exemptions. Yet eliminating these provisions is politically difficult. Beginning in 2009, sixth grade girls in Washington, DC were required to receive the HPV vaccine or submit a one-time opt-out form. In 2014, the requirement was expanded to all students grades 6-12, and those not vaccinating were required to opt-out annually. I show that the movement from a one-time opt-out provision to an annual requirement increased the probability that teen girls in Washington, DC initiated HPV vaccination by 11 percentage points. Teen boys were 20 percentage points more likely to be vaccinated. Back-of-the-envelope calculations suggest 7 fewer cases of cervical cancer and 41 fewer cases of oropharyngeal cancer for the 33,000 enrolled during the 2017/2018 year. Using the initial value of cancer care and the value of a statistical life year, my estimates imply nearly $36 million in savings compared to $1.5 million spent on vaccination. In generalizing these results to other states, effect sizes even one-tenth the size of my most conservative estimate would imply meaningful reductions in the nationwide incidence of HPV-related cancers.

Individual preferences for voluntary vs. mandatory vaccination policies: an experimental analysis

BACKGROUND

More and more countries are discussing the introduction of mandatory vaccination policies. Yet, little is known about individuals' actual preferences for voluntary vs. mandatory vaccination policies, and the psychological processes underlying such preferences. Objective of the present research was to investigate the development of individual preferences for voluntary and mandatory vaccination policies.

METHODS

We conducted a controlled laboratory study (N = 168) using a repeated interactive vaccination game with decision-contingent monetary incentives. In each round, participants decided in favour of either a voluntary or a mandatory vaccination policy, followed by the vaccination decision (voluntary policy) or vaccination (mandatory policy) which both resulted in actual (financial) consequences.

RESULTS

We observe large heterogeneity in participants' preferences for the voluntary vs. mandatory policy. Under voluntary vaccination, the preference for the mandatory policy increased with decreasing vaccination rates (and increasing risk of infection). In contrast, experiencing vaccine-adverse events under mandatory vaccination increased the preference for the voluntary policy. The latter effect was larger for individuals with a negative (vs. positive) attitude toward vaccination. Overall, as individuals gathered experiences under both the voluntary and the mandatory policy, the preference for voluntary vaccination policy increased over time.

CONCLUSIONS

Individuals are more willing to accept mandatory vaccination policies when vaccination rates are low. In the long run, the occurrence of vaccine-adverse events may spark opposition to mandatory vaccination.

Pneumococcal Vaccination Mandates for Child Care: Impact of State Laws on Vaccination Coverage at 19-35 Months

INTRODUCTION

Vaccination mandates for elementary and middle school attendance have been shown to increase vaccination rates and decrease the burden of vaccine-preventable diseases. Fewer studies have evaluated similar requirements for child care attendance. This study provides robust, quasi-experimental estimates of the effect of state laws mandating the pneumococcal conjugate vaccine for child care attendance on vaccination coverage among children aged 19-35 months.

METHODS

Using provider-verified immunization histories from the 2001-2018 waves of the National Immunization Survey-Child and leveraging the staggered implementation of vaccination requirements across states, a generalized difference-in-differences approach was implemented to compare regression-adjusted changes in vaccination coverage among children in states with and without a child care mandate for the pneumococcal conjugate vaccine. The dynamics of estimated treatment effects were analyzed using an event study analysis. All data analyses were conducted in 2019‒2020.

RESULTS

State adoption of a child care mandate for the pneumococcal conjugate vaccine increased the likelihood that resident children aged 19-35 months completed the 4-dose pneumococcal conjugate vaccine series by 3.12 percentage points (p<0.01). Statistically significant gains in pneumococcal conjugate vaccine coverage were identified in the first year following policy implementation and were found to persist over a period of ≥7 years.

CONCLUSIONS

Results indicate that state adoption of a child care mandate for the pneumococcal conjugate vaccine leads to an increase in the proportion of resident children aged 19-35 months who are up to date with pneumococcal conjugate vaccine.

The contagion externality of a superspreading event: The Sturgis Motorcycle Rally and COVID-19

Large in-person gatherings of travelers who do not socially distance are classified as the "highest risk" for COVID-19 spread by the Centers for Disease Control and Prevention (CDC). From August 7-16, 2020, nearly 500,000 motorcycle enthusiasts converged on Sturgis, South Dakota for its annual rally in an environment without mask-wearing requirements or other mitigating policies. This study is the first to explore this event's public health impacts. First, using anonymized cell phone data, we document that foot traffic at restaurants/bars, retail establishments, and entertainment venues rose substantially at event locations. Stay-at-home behavior among local residents fell. Second, using a synthetic control approach, we find that the COVID-19 case rate increased substantially in Meade County and in the state of South Dakota in the month following the Rally. Finally, using a difference-in-differences model to assess nationwide spread, we find that following the Sturgis event, counties outside of South Dakota that contributed the highest inflows of rally attendees experienced a 6.4-12.5% increase in COVID-19 cases relative to counties without inflows. Our findings highlight that local policy decisions assessing the tradeoff between local economic benefits and COVID-19 health costs will not be socially optimal in the presence of large contagion externalities.

Vaccination take-up and health: Evidence from a flu vaccination program for the elderly

We analyze the effects of a vaccination program providing free flu vaccine to individuals aged 65 or more on take-up behavior and hospitalization. Using both administrative and survey data, we implement a regression discontinuity design around the threshold at age 65, and find that the effect of the program on take-up ranges between 70% and 90% of the average vaccination rate for individuals aged less than 65. We show that this effect is not entirely driven by an income channel, but also depends on the expected benefits of vaccination. The results on health outcomes provide suggestive evidence that the program reduces the likelihood of emergency hospitalization.

The impact of school-entry mandates on social inequalities in human papillomavirus vaccination

Fundamental cause theory (FCT) is influential for explaining the enduring relationship between social position and health, yet few empirical studies test FCT's contention that policy supporting the equal distribution of interventions across populations can help reduce health inequalities. Following human papillomavirus (HPV) vaccine approval, complex socioeconomic and racial-ethnic inequalities emerged in distinct stages of the diffusion of this health innovation. Virginia and the District of Columbia were the first U.S. jurisdictions to implement school-entry HPV vaccination mandates for sixth-grade girls, offering an opportunity to test whether inequalities in HPV vaccination are mitigated by policy that seeks to standardize the age of vaccine administration and remove barriers to knowledge about the vaccine. Using data from the 2008, 2009, 2011, 2012, and 2013 National Immunization Survey-Teen (N = 4579) and a triple-difference approach, this study tests whether vaccine mandates are associated with smaller socioeconomic and racial-ethnic inequalities in health provider recommendation and vaccine uptake. It finds mandates were associated with improvements in provider recommendation and vaccine uptake for some socioeconomic and racial-ethnic groups. However, mandates also likely led to a decline in HPV vaccine series completion overall. Implications of these findings for informing FCT and vaccination policy are discussed.

Not just conspiracy theories: Vaccine opponents and proponents add to the COVID-19 'infodemic' on Twitter

In February 2020, the World Health Organization announced an 'infodemic' -- a deluge of both accurate and inaccurate health information -- that accompanied the global pandemic of COVID-19 as a major challenge to effective health communication. We assessed content from the most active vaccine accounts on Twitter to understand how existing online communities contributed to the 'infodemic' during the early stages of the pandemic. While we expected vaccine opponents to share misleading information about COVID-19, we also found vaccine proponents were not immune to spreading less reliable claims. In both groups, the single largest topic of discussion consisted of narratives comparing COVID-19 to other diseases like seasonal influenza, often downplaying the severity of the novel coronavirus. When considering the scope of the 'infodemic,' researchers and health communicators must move beyond focusing on known bad actors and the most egregious types of misinformation to scrutinize the full spectrum of information -- from both reliable and unreliable sources -- that the public is likely to encounter online.

Effectiveness of post-exposure prophylaxis during varicella outbreaks among primary and middle school students in Shanghai: An analysis of three-year surveillance data

OBJECTIVES

To evaluate the effectiveness of post-exposure prophylaxis conducted during varicella outbreaks among students in Shanghai.

METHODS

Surveillance data were collected from September 1, 2013 to December 31, 2016 involving 3524 susceptible students in 109 primary and middle school classes where emergency vaccinations (EVs) had been administered. Students were divided into two groups according to their prior vaccination (PV) varicella vaccine status. A secondary attack rate was used to compare EV and non-EV groups using a chi-squared test. Stratification analyses were performed, adjusting for the EV administration date, the vaccination coverage rate, and the number of cases prior to the EV.

RESULTS

The effectiveness rate was 92.2% (95% confidence interval (CI): 37.1-99.0%) when EV was applied within 3 days following the outbreak onset date, and 95.2% (95% CI: 79.9-98.8%) when vaccination coverage was ≥80% among students with PV. When students with PV received an EV for varicella within 3 days, the effectiveness rate was 100%.

CONCLUSIONS

EV showed high protective effectiveness for varicella during outbreaks, especially if administered within 3 days of an outbreak and in conjunction with a high coverage rate.

Information, education, and health behaviors: Evidence from the MMR vaccine autism controversy

In the wake of strong, although later refuted, claims of a link between autism and the measles-mumps-rubella (MMR) vaccine, I examine whether fewer parents immunized or delayed vaccinations for their children and if there was a differential response by mother's education level. Using various controls and a differencing strategy that compares in MMR take-up with other vaccines, I find that the MMR-autism controversy led to a decline in the immediate years and that there were negative spillovers onto other vaccines. I also find evidence that more highly educated mothers responded more strongly to the controversy either by not immunizing their children altogether or, to a lesser degree, delaying vaccination. Moreover, the educational gap was greater in states where there was greater media attention devoted to the controversy. This is consistent with the health allocative efficiency hypothesis whereby part of the education gradient in health outcomes is due to more-educated individuals absorbing and responding to health information more quickly. However, unlike in the United Kingdom, where previous studies find that the gap was eliminated after the link was refuted, the evidence for the United States suggests that the educational gap persisted.

Examination of universal purchase programs as a driver of vaccine uptake among US States, 1995-2014

BACKGROUND

Immunization against numerous potentially life-threatening illnesses has been a great public health achievement. In the United States, the Vaccines for Children (VFC) program has provided vaccines to uninsured and underinsured children since the early 1990s, increasing vaccination rates. In recent years, some states have adopted Universal Purchase (UP) programs with the stated aim of further increasing vaccination rates. Under UP programs, states also purchase vaccines for privately-insured children at federally-contracted VFC prices and bill private health insurers for the vaccines through assessments.

METHODS

In this study, we estimated the effect of UP adoption in a state on children's vaccination rates using state-level and individual-level data from the 1995-2014 National Immunization Survey. For the state-level analysis, we performed ordinary least squares regression to estimate the state's vaccination rate as a function of whether the state had UP in the given year, state demographic characteristics, other vaccination policies, state fixed effects, and a time trend. For the individual analysis, we performed logistic regression to estimate a child's likelihood of being vaccinated as a function of whether the state had UP in the given year, the child's demographic characteristics, state characteristics and vaccine policies, state fixed effects, and a time trend. We performed separate regressions for each of nine recommended vaccines, as well as composite measures on whether a child was up-to-date on all required vaccines.

RESULTS

In the both the state-level and individual-level analyses, we found UP had no significant (p < 0.10) effect on any of the vaccines or composite measures in our base case specifications. Results were similar in alternative specifications.

CONCLUSIONS

We hypothesize that UP was ineffective in increasing vaccination rates. Policymakers seeking to increase vaccination rates would do well to consider other policies such as addressing provider practice issues and vaccine hesitancy.

Factors associated with the pricing of childhood vaccines in the U.S. public sector

Vaccine purchase cost has grown substantially over the last few decades. A closer look at vaccine prices reveals that not all vaccines shared the same increasing pattern. Various factors, such as vaccine attributes, competition, and supply shortages, could relate to price changes. In this study, we examined whether a variety of factors influenced the prices of noninfluenza childhood vaccines purchased in the public sector from 1996 to 2014. The association differed among price-capped vaccines and combination vaccines. There was an increasing time trend in real prices for non-price-capped vaccines, which was mostly offset by the effect of market longevity. The effect of competition in lowering prices was more pronounced among non-price-capped vaccines when manufacturer and vaccine component fixed effects were excluded. Supply shortage, manufacturer name change, and number of vaccine doses in series showed no effect. The results may help policy makers better understand price behaviors and make more informed decisions in vaccine planning and financing.

Perceptions of caregivers and providers regarding the potential introduction of the varicella vaccine to the childhood immunisation schedule in New Zealand: A qualitative exploratory study

AIM

The varicella vaccine has been proposed to be added to the childhood immunisation schedule in New Zealand as the fourth injectable at the 15-month event. We sought to understand the perceptions of caregivers and health-care providers regarding the potential introduction of routine varicella vaccination.

METHODS

A qualitative exploratory study was conducted using semi-structured interviews with caregivers and providers (N = 20) in Auckland. Key themes from the interviews were identified through thematic analysis using a combination of deductive and inductive coding.

RESULTS

All of the participants were aware of varicella but levels of awareness varied among caregivers regarding the varicella vaccine. Participants expressed positive support towards universal varicella vaccination and a high intention to vaccinate if available as a routine vaccine. However, many concerns were raised about multiple injections at a single immunisation visit, and participants suggested alternative scheduling options.

CONCLUSION

The results indicated a need to raise awareness among caregivers about the varicella vaccine, focusing on positive health beliefs about vaccination in terms of protecting the child's health and reducing the impact of a child getting varicella on the family. Health-care providers and government health authorities may play an important role in increasing positive health beliefs about the varicella vaccine. Should the varicella vaccine be introduced as proposed, our findings recommend an educational campaign to address both caregiver and provider concerns about multiple injections and how to manage alternative immunisation schedules. These insights may help inform national strategies for the proposed addition to increase acceptance of the varicella vaccination.

Effectiveness of vaccination recommendations versus mandates: Evidence from the hepatitis A vaccine

I provide novel evidence on the effectiveness of two vaccination policies - simple non-binding recommendations to vaccinate versus mandates requiring vaccination prior to childcare or kindergarten attendance - in the context of the only disease whose institutional features permit a credible examination of both: hepatitis A. Using provider-verified immunization data I find that recommendations significantly increased hepatitis A vaccination rates among young children by at least 20 percentage points, while mandates increase rates by another 8 percentage points. These policies also significantly reduced population hepatitis A incidence. My results suggest a range of policy options for addressing suboptimally low population vaccination rates.

Increasing Immunization Compliance by Reducing Provisional Admittance

Students in Vermont with incomplete or undocumented immunization status are provisionally admitted to schools and historically had a calendar year to resolve their immunization status. The process of resolving these students’ immunization status was challenging for school nurses. We conducted a school-based quality improvement effort to increase student compliance with Vermont immunization regulations using a collaborative learning approach with public health school liaisons and school nurses from public schools to reduce provisional admittance in 2011–2012. Strategies included using a tracking system, accessing the immunization registry, promoting immunization importance, tracking immunization plans, and working with medical homes to update records. Participating school nurses observed decreases in the number of provisionally admitted students, although this reduction was not significantly different than matched comparison schools. We also found the number of provisionally admitted students fluctuated throughout the year and resolving the immunization status of New Americans and exchange students required special attention. Our approach supports the coordinated school health model and demonstrates the critical role school nurses play in improving population health outcomes.

Effectiveness and acceptability of parental financial incentives and quasi-mandatory schemes for increasing uptake of vaccinations in preschool children: systematic review, qualitative study and discrete choice experiment

BACKGROUND

Uptake of preschool vaccinations is less than optimal. Financial incentives and quasi-mandatory policies (restricting access to child care or educational settings to fully vaccinated children) have been used to increase uptake internationally, but not in the UK.

OBJECTIVE

To provide evidence on the effectiveness, acceptability and economic costs and consequences of parental financial incentives and quasi-mandatory schemes for increasing the uptake of preschool vaccinations.

DESIGN

Systematic review, qualitative study and discrete choice experiment (DCE) with questionnaire.

SETTING

Community, health and education settings in England.

PARTICIPANTS

Qualitative study - parents and carers of preschool children, health and educational professionals. DCE - parents and carers of preschool children identified as 'at high risk' and 'not at high risk' of incompletely vaccinating their children.

DATA SOURCES

Qualitative study - focus groups and individual interviews. DCE - online questionnaire.

REVIEW METHODS

The review included studies exploring the effectiveness, acceptability or economic costs and consequences of interventions that offered contingent rewards or penalties with real material value for preschool vaccinations, or quasi-mandatory schemes that restricted access to 'universal' services, compared with usual care or no intervention. Electronic database, reference and citation searches were conducted.

RESULTS

Systematic review - there was insufficient evidence to conclude that the interventions considered are effective. There was some evidence that the quasi-mandatory interventions were acceptable. There was insufficient evidence to draw conclusions on economic costs and consequences. Qualitative study - there was little appetite for parental financial incentives. Quasi-mandatory schemes were more acceptable. Optimising current services was consistently preferred to the interventions proposed. DCE and questionnaire - universal parental financial incentives were preferred to quasi-mandatory interventions, which were preferred to targeted incentives. Those reporting that they would need an incentive to vaccinate their children completely required around £110. Those who did not felt that the maximum acceptable incentive was around £70.

LIMITATIONS

Systematic review - a number of relevant studies were excluded as they did not meet the study design inclusion criteria. Qualitative study - few partially and non-vaccinating parents were recruited. DCE and questionnaire - data were from a convenience sample.

CONCLUSIONS

There is little current evidence on the effectiveness or economic costs and consequences of parental financial incentives and quasi-mandatory interventions for preschool vaccinations. Universal incentives are likely to be more acceptable than targeted ones. Preferences concerning incentives versus quasi-mandatory interventions may depend on the context in which these are elicited.

FUTURE WORK

Further evidence is required on (i) the effectiveness and optimal configuration of parental financial incentive and quasi-mandatory interventions for preschool vaccinations - if effectiveness is confirmed, further evidence is required on how to communicate this to stakeholders and the impact on acceptability; and (ii) the acceptability of parental financial incentive and quasi-mandatory interventions for preschool vaccinations to members of the population who are not parents of preschool children or relevant health professionals. Further consideration should be given to (i) incorporating reasons for non-vaccination into new interventions for promoting vaccination uptake; and (ii) how existing services can be optimised.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012003192.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Increasing Coverage of Appropriate Vaccinations: A Community Guide Systematic Economic Review

CONTEXT

Population-level coverage for immunization against many vaccine-preventable diseases remains below optimal rates in the U.S. The Community Preventive Services Task Force recently recommended several interventions to increase vaccination coverage based on systematic reviews of the evaluation literature. The present study provides the economic results from those reviews.

EVIDENCE ACQUISITION

A systematic review was conducted (search period, January 1980 through February 2012) to identify economic evaluations of 12 interventions recommended by the Task Force. Evidence was drawn from included studies; estimates were constructed for the population reach of each strategy, cost of implementation, and cost per additional vaccinated person because of the intervention. Analyses were conducted in 2014.

EVIDENCE SYNTHESIS

Reminder systems, whether for clients or providers, were among the lowest-cost strategies to implement and the most cost effective in terms of additional people vaccinated. Strategies involving home visits and combination strategies in community settings were both costly and less cost effective. Strategies based in settings such as schools and MCOs that reached the target population achieved additional vaccinations in the middle range of cost effectiveness.

CONCLUSIONS

The interventions recommended by the Task Force differed in reach, cost, and cost effectiveness. This systematic review presents the economic information for 12 effective strategies to increase vaccination coverage that can guide implementers in their choice of interventions to fit their local needs, available resources, and budget.

Systematic review of the effect of immunization mandates on uptake of routine childhood immunizations

PURPOSE

The efficacy of immunization mandates for childcare or school entry is a long-standing controversy. The United States (US) adopted school entry immunization mandates in the 1800s, while most countries still do not have mandates. The objective of this systematic review was to analyze the evidence that immunization uptake increases with mandates.

METHODS

A search was conducted for studies that compared immunization uptake in a population prior to and after mandates, or in similar populations with one group having and the other not having mandates. Data were extracted and synthesized qualitatively due to the heterogeneity of study design.

RESULTS

Eleven before-and-after studies and ten studies comparing uptake in similar populations with and without mandates were included. Studies were from the US (n = 18), France (n = 1) and Canada (n = 2). Eleven of the 21 studies looked at middle school mandates. All but two studies showed at least a trend towards increased uptake with mandates. Higher uptake was associated with a more long-standing mandate.

CONCLUSIONS

Immunization mandates have generally led to increased short-term and long-term uptake in the group to whom the mandate applies. Many studies have centered around middle school mandates in the US and there is a paucity of studies of childcare mandates or of studies of mandates in other countries or in settings with relatively high baseline immunization uptake.

Parents' and providers' attitudes toward school-located provision and school-entry requirements for HPV vaccines

OBJECTIVE

To determine parents' and providers' attitudes toward school-located provision and school-entry requirements for HPV vaccination.

METHODS

Parents/guardians of 11-17 y old girls and pediatric healthcare providers at one inner-city public clinic and three private practices completed semi-structured interviews in 2012-2013. Participants were asked open-ended questions regarding their attitudes toward school-located provision and school-entry requirements for HPV vaccination. Parents' answers were analyzed with relationship to whether their daughters had not initiated, initiated but not completed, or completed the HPV vaccine series. Qualitative analysis was used to identify themes related to shared views.

RESULTS

129 parents/guardians and 34 providers participated. 61% of parents supported providing HPV vaccinations in schools, citing reasons of convenience, improved access, and positive peer pressure. Those who opposed school-located provision raised concerns related to privacy and the capacity of school nurses to manage vaccine-related reactions. Parents whose daughters had not completed the series were more likely to intend to vaccinate their daughters in schools (70%) and support requirements (64%) than parents who had not initiated vaccination (42% would vaccinate at school, 46% support requirements) or completed the series (42% would vaccinate at school, 32% support requirements; p < 0 .05 for all comparisons). 81% of providers supported offering vaccination in schools, wanting to take advantage of the captive audience, improve vaccine completion rates, and decrease the administrative burden on medical office staff, but were concerned about adequate information transfer between schools and medical offices. Only 32% of providers supported school-entry requirements, largely because they felt that a requirement might provoke a public backlash that could further hinder vaccination efforts.

CONCLUSIONS

School-located provision of HPV vaccination was widely accepted by healthcare providers and parents whose children have not completed the series, indicating that this venue might be a valuable addition to improve completion rates. Support for school-entry requirements was limited among both parents and healthcare providers.

THE EFFECT OF STATE INSURANCE MANDATES ON INFANT IMMUNIZATION RATES

While US infant immunization rates have been increasing in the last 20 years, the cost of fully immunizing a child with all recommended vaccines has almost tripled. This is partly not only due to new additions in the list of recommended vaccines but also due to the use of new, safer, but more expensive technologies in vaccine production and distribution. In recent years, many states have mandated that recommended childhood vaccines be covered by private health insurance companies. Currently, there are 33 states with such a mandate. In this paper, I examine whether the introduction of mandates on private insurers affected immunization rates. Using state and time variation, I find that mandates increased the immunization rate for three vaccines--the diphtheria-tetanus-pertussis, polio, and measles-mumps-rubella vaccines--by about 1.8 percentage points. These results may provide a lower bound for the expected effect of the Affordable Care Act, which mandates coverage of childhood vaccines for all private insurers in the USA. I also find evidence that the mandates shifted a significant portion of vaccinations from publicly funded sources to private ones, with a decline in public health clinic visits and an increase in vaccinations at hospitals and doctor's offices.

Strategies intended to address vaccine hesitancy: Review of published reviews

When faced with vaccine hesitancy, public health authorities are looking for effective strategies to address this issue. In this paper, the findings of 15 published literature reviews or meta-analysis that have examined the effectiveness of different interventions to reduce vaccine hesitancy and/or to enhance vaccine acceptance are presented and discussed. From the literature, there is no strong evidence to recommend any specific intervention to address vaccine hesitancy/refusal. The reviewed studies included interventions with diverse content and approaches that were implemented in different settings and targeted various populations. Few interventions were directly targeted to vaccine hesitant individuals. Given the paucity of information on effective strategies to address vaccine hesitancy, when interventions are implemented, planning a rigorous evaluation of their impact on vaccine hesitancy/vaccine acceptance will be essential.

An evaluation of voluntary 2-dose varicella vaccination coverage in New York City public schools

OBJECTIVES

We assessed coverage for 2-dose varicella vaccination, which is not required for school entry, among New York City public school students and examined characteristics associated with receipt of 2 doses.

METHODS

We measured receipt of either at least 1 or 2 doses of varicella vaccine among students aged 4 years and older in a sample of 336 public schools (n = 223 864 students) during the 2010 to 2011 school year. Data came from merged student vaccination records from 2 administrative data systems. We conducted multivariable regression to assess associations of age, gender, race/ethnicity, and school location with 2-dose prevalence.

RESULTS

Coverage with at least 1 varicella dose was 96.2% (95% confidence interval [CI] = 96.2%, 96.3%); coverage with at least 2 doses was 64.8% (95% CI = 64.6%, 64.9%). Increasing student age, non-Hispanic White race/ethnicity, and attendance at school in Staten Island were associated with lower 2-dose coverage.

CONCLUSIONS

A 2-dose varicella vaccine requirement for school entry would likely improve 2-dose coverage, eliminate coverage disparities, and prevent disease.

A review of factors affecting vaccine preventable disease in Japan

Japan is well known as a country with a strong health record. However its incidence rates of vaccine preventable diseases (VPD) such as hepatitis B, measles, mumps, rubella, and varicella remain higher than other developed countries. This article reviews the factors that contribute to the high rates of VPD in Japan. These include historical and political factors that delayed the introduction of several important vaccines until recently. Access has also been affected by vaccines being divided into government-funded "routine" (eg, polio, pertussis) and self-pay "voluntary" groups (eg, hepatitis A and B). Routine vaccines have higher rates of administration than voluntary vaccines. Administration factors include differences in well child care schedules, the approach to simultaneous vaccination, vaccination contraindication due to fever, and vaccination spacing. Parental factors include low intention to fully vaccinate their children and misperceptions about side effects and efficacy. There are also provider knowledge gaps regarding indications, adverse effects, interval, and simultaneous vaccination. These multifactorial issues combine to produce lower population immunization rates and a higher incidence of VPD than other developed countries. This article will provide insight into the current situation of Japanese vaccinations, the issues to be addressed and suggestions for public health promotion.

Parental financial incentives for increasing preschool vaccination uptake: systematic review

BACKGROUND AND OBJECTIVE

Financial incentives have been used to promote vaccination uptake but are not always viewed as acceptable. Quasimandatory policies, such as requiring vaccinations for school enrollment, are widely implemented in some countries. A systematic review was conducted to determine the effectiveness, acceptability, and economic costs and consequences of parental financial incentives and quasimandatory schemes for increasing the uptake of preschool vaccinations in high-income countries.

METHODS

Electronic databases and gray literature were searched for randomized controlled trials, controlled before-and-after studies, and time series analyses examining the effectiveness of parental financial incentives and quasimandatory schemes, as well as any empirical studies exploring acceptability. All included studies were screened for information on economic costs and consequences. Two reviewers independently assessed studies for inclusion, extracted data, and assessed the quality of selected articles by using established instruments. Studies were synthesized in narrative reviews.

RESULTS

Four studies on the effectiveness and 6 on the acceptability of parental financial incentives and quasimandatory interventions met the inclusion criteria. Only 1 study reported on costs and consequences. Studies of effectiveness had low risk of bias but displayed substantial heterogeneity in terms of interventions and methods.

CONCLUSIONS

There was insufficient evidence to conclude whether these interventions were effective. Studies of acceptability suggested a preference, in settings where this already occurs, for incentives linking vaccinations to access to education. There was insufficient evidence to draw conclusions on economic costs and consequences.

A systematic review of interventions for reducing parental vaccine refusal and vaccine hesitancy

Unvaccinated individuals pose a public health threat to communities. Research has identified many factors associated with parental vaccine refusal and hesitancy toward childhood and adolescent immunizations. However, data on the effectiveness of interventions to address parental refusal are limited. We conducted a systematic review of four online databases to identify interventional studies. We used criteria recommended by the WHO's Strategic Advisory Group of Experts on immunization (SAGE) for the quality assessment of studies. Intervention categories and outcomes were evaluated for each body of evidence and confidence in overall estimates of effect was determined. There is limited evidence to guide implementation of effective strategies to deal with the emerging threat of parental vaccine refusal. There is a need for appropriately designed, executed and evaluated intervention studies to address this gap in knowledge.

Correlates for second-dose varicella vaccination in school-age children in a managed care organization in California

OBJECTIVE

To identify correlates of nonadherence to the recommendation for routine second-dose varicella vaccination in a diverse sample of school-age children.

METHODS

A total of 67,977 children of 4-6 years (51% male, 50% Hispanic) were included in this retrospective cohort study. The second-dose varicella vaccination history was evaluated by using the Kaiser Immunization Tracking System. Correlation and multivariable regression analyses were used to test the association between potential correlates and nonadherence to the second-dose varicella vaccination.

RESULTS

Four-year-old children had a significantly higher vaccination rate (76.1%) than 5-year-olds (43.2%) and 6-year-olds (17.3%) by 12 months after the implementation of routine second-dose varicella vaccination. Non-Hispanic white race [rate ratio (RR): 1.13 (95% CI: 1.11-1.15)], living in an area of >75% adults with a high-school diploma [RR: 1.17 (95% CI: 1.14-1.20)], and having a primary care provider specializing in family medicine [RR: 1.15 (95% CI: 1.11-1.18)] significantly correlated with nonadherence. Missed opportunity was found in 59.7% (n=20,465) of children who did not receive the second-dose varicella vaccine in spite of at least 1 outpatient visit and in 15.8% (n=5407) who received some other vaccines during the follow-up period.

CONCLUSIONS

Efforts targeting non-Hispanic white and black children, parents with a high education level and family medicine physicians might improve uptake of the routine 2-dose varicella vaccination. Incorporation of a requirement for the second-dose varicella vaccine into the school law might help achieve high adherence to the routine 2-dose varicella vaccination in school-age children.