Higher Vaccine Coverage Tied to Mandatory Vaccination in Europe

Mandatory vaccination policies in Europe are associated with higher immunization coverage against measles and pertussis and lower incidence of measles, according to a study published online January 13 in Pediatrics.

Measles vaccination coverage from 2006 to 2015 was an average 3.71 percentage points higher in countries with mandatory vaccination compared with those without such policies. Pertussis vaccination coverage from 2006 to 2016 similarly had a rate 2.14 percentage points higher in countries with mandates. Mandatory vaccination without nonmedical exemptions had very similar numbers: 3.8 and 2.07 points higher for measles and pertussis vaccination coverage, respectively.

"Countries with a fine for noncompliance experienced incidence rates of less than half that of countries without mandatory vaccination for both measles and pertussis," write Olivia M. Vaz, MPH, of Emory University's Rollins School of Public Health in Atlanta, Georgia, and colleagues. The reduction for pertussis incidence in countries with mandates, however, was nonsignificant.

European Mandates Have Financial Penalties

The findings also revealed a 1.1 percentage point higher pertussis vaccination rate and 0.8 percentage point higher measles vaccination rate for every €500 in fines parents had to pay for not vaccinating their children (P ≤ .0001).

"Financial penalties could be an effective measure in a comprehensive mandatory vaccination program, although they need to accompany other measures, including a stable vaccine supply and vaccine education, to reach those who refuse to vaccinate," the authors write

Australia's rates of fully immunized children reached record highs after the country implemented a policy revoking family tax benefits for those who did not vaccinate, the authors note, but they add that vaccine refusers tended to live in wealthier areas, suggesting that "financial disincentives may not be adequate" if those refusing are more able to go without the benefits.

What's key to successful vaccination mandates is "tipping the balance of convenience" so that it's easier for parents to vaccinate their children than it is to avoid doing so, senior author Saad B. Omer, MBBS, PhD, MPH, also from Emory University, told Medscape Medical News. Mandatory vaccination policies "don't have to be a cudgel; they can be nudges," he said, if policymakers find the sweet spot between encouraging vaccination and not exacerbating socioeconomic inequalities or pushing so hard that the policy inspires a backfire effect.

"The majority of parents actually support requiring vaccinations and feel that kids at school should be vaccinated" without the option of nonmedical exemptions, Sean O'Leary, MD, MPH, an associate professor of pediatrics at the University of Colorado and a spokesperson for the American Academy of Pediatrics, told Medscape Medical News. O'Leary and Yvonne Maldonado, MD, of Stanford University in California, coauthored an accompanying editorial on how European nations' vaccination policies have implications for the United States.

O'Leary hasn't seen any US data on attitudes toward financial penalties, but he said it's something policymakers should consider since outbreaks resulting from low vaccination rates rack up millions of dollars in public health costs.

"It's clear that the parents choosing not to get their children vaccinated are making a conscious choice and costing all of us money," said O'Leary. "If state legislators look at it from a purely economic standpoint, they may consider some of those mechanisms to cover the cost of their choice."

Mandates Linked to Greater Immunization Coverage

The study authors relied on data from the World Health Organization and the European Centre for Disease Prevention and Control to investigate mandatory vaccination policies in 29 European countries and their association with disease incidence and vaccine coverage for both measles and pertussis. The countries included members of the European Union plus Iceland and Norway.

The authors say they focused on measles since outbreaks have been a major driver of policy change in Europe. Measles and pertussis are also both highly infectious, so "that even small changes in vaccine coverage can impact disease incidence," and both have "good surveillance of vaccine coverage and disease incidence," they explain.

The researchers adjusted their analysis for several covariates: the percentage of the population living in urban areas, percentage of population younger than 14 years, median age of residents, proportion of adults aged 24 to 65 with at least a lower-secondary education, universal healthcare service index, and wealth distribution (as a measure of inequality).

Seven countries had mandatory vaccination policies: Slovakia, Slovenia, Czech Republic, Poland, Latvia, Bulgaria, and Hungary. All but Latvia had a financial penalty for nonvaccination. Only Latvia and Bulgaria offered nonmedical exemptions, which required parents to receive information about vaccination online or from their healthcare provider or to discuss the decision with their child's provider and then provide written refusal.

After adjustment to compare financial penalties across countries, Hungary had the highest fine, up to $1800 (€1600) in 2016, if parents did not get their children the required vaccinations. Bulgaria's fine was lowest, about $170 (€150).

Despite Bulgaria having the highest measles incidence, at 32.9 cases per 100,000 people per year, measles incidence was 86% lower in countries with mandatory vaccination policies with financial penalties (adjusted incidence rate ratio [aIRR], 0.14) or without nonmedical exemptions (aIRR, 0.14). Including countries with nonmedical exemptions, the association of a mandate with a 62% reduced measles incidence was not significant.

Pertussis incidence was not significantly different across countries with a mandatory vaccination policy vs those without one.

What Works in Vaccination Policy

The small number of countries with mandates and the heterogeneity of the policies precluded drawing any conclusions about the most effective types of mandates or any shared factors among the countries. Nevertheless, the evidence base on vaccination mandates in general suggests that requiring parents to talk to their child's healthcare provider about vaccines is among the most effective, Omer said.

"If I were to choose one thing to add to a mandate, it's to add healthcare provider counseling, where there's true informed consent," he said. After that, including any type of administrative hurdle and requiring catch-up vaccinations in families that had previous nonmedical exemptions are helpful, Omer said.

Those who oppose vaccination are very vocal but also a very, very small group, O'Leary said, so hearing more from everyone else may help reinforce vaccination norms.

"I'd like to see more of pro-vaccine parents getting a voice so that they can help influence our population to show that [vaccination] is the right choice," O'Leary explained. "We don't hear enough from those parents" compared with authority figures, such as doctors and researchers, or antivaccination advocates. He also noted the value of policies that make vaccination coverage rates transparent at schools and daycare centers so that parents know the rates at their children's institutions.

Low vaccination rates are a safety issue, he said, and parents may opt to avoid schools or centers with low coverage. "I think that has a lot of potential for moving this needle in more of a positive way," O'Leary said.

The research had no external funding. The study authors and editorialists have disclosed no relevant financial relationships.

Pediatrics. Published online January 13, 2020. Full text, Editorial

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