Parental Vaccine Hesitancy in Italy - Results from a National Survey

"The integration of multiple strategies and interventions, targeting both population and health professionals, is necessary to reduce parental hesitancy..."

In Italy, childhood vaccination coverage rates for various vaccine-preventable diseases have been decreasing since 2013, and in 2016, the vaccination coverage rate for poliomyelitis in children at 24 months of age was below 95%. Interviews carried out in 2013 by staff from the World Health Organization (WHO) regional offices with immunisation managers of 13 countries, representing the 6 WHO Regions, confirmed that causes of vaccine hesitancy varied in the different countries and also throughout the same country. To understand the situation in Italy, in 2016, a group of researchers conducted a cross-sectional survey to estimate vaccine hesitancy and investigate its determinants.

The survey, coordinated by the Italian National Institute of Public Health (Istituto Superiore di Sanità), was conducted in the period December 2015 - June 2016, among parents of children aged 16-36 months. Data were collected: (i) through a computer/mobile assisted web interviewing survey that sampled participants from an online panel of Italian families, stratified to reflect the geographical distribution of the reference population by macro area (Northern, Central, and Southern Italy); and (ii) among parents attending paediatricians' offices and nurseries in 5 Italian regions (Emilia-Romagna, Friuli Venezia Giulia, Marche, Piemonte, Puglia) who voluntarily completed a printed questionnaire.

To define vaccine hesitancy, measles and tetanus vaccinations were used as proxies of measles-mumps-rubella (MMR) and hexavalent vaccinations, respectively. Parents were classified as: (i) pro-vaccine if their child was vaccinated within the recommended age intervals for both antigens, (ii) vaccine-hesitant if vaccination was delayed or interrupted for at least one of the two antigens, if their child was unvaccinated for one of the two antigens, or if their child was not vaccinated at all but parents were still uncertain about the decision of vaccinating him or her, (iii) anti-vaccine if their child was unvaccinated for both antigens and parents were fully convinced of the decision not to vaccinate. Parents were questioned about the main reason for refusal, delay, or interruption. Multivariable logistic regression was used to investigate factors associated with hesitancy.

A total of 3,130 questionnaires were analysed: 83.7% of parents were pro-vaccine, 15.6% vaccine-hesitant, and 0.7% anti-vaccine. Safety concerns are the main reported reason for refusing (38.1%) or interrupting (42.4%) vaccination. The main reported reason for having delayed at least one of these vaccinations was the presence of contraindications (47.5%), whereas most of those who interrupted or refused vaccination made this decision because of doubts on vaccine safety (41.4 and 41.3%, respectively). Anti-vaccine and hesitant parents are significantly more afraid than pro-vaccine parents of short-term (85.7% and 79.7% vs 60.4%) and long-term (95.2% and 72.3% vs 43.7%) vaccine adverse reactions. Most pro-vaccine and hesitant parents agree about the benefits of vaccinations.

Family paediatricians are considered a reliable source of information by most pro-vaccine and hesitant parents (96.9% and 83.3%, respectively), against 45% of anti-vaccine parents. Most hesitant (76.6%) and anti-vaccine (85.7%) parents think that healthcare professionals give information only about the benefits of vaccination but not about their risks, compared to 54.0% of pro-vaccine parents (p < .001). When asked if they think their family paediatrician spends enough time discussing vaccination, 71.8% of pro-vaccine and 64.2% of hesitant said yes, compared to 36.8% of anti-vaccine parents (p < .001). The proportion of parents who believe that public vaccination service staff spend enough time responding to vaccine-related doubts is low in all three groups but especially among anti-vaccine parents: 60.3% pro-vaccine, 42.9% hesitant and 19.1% anti-vaccine parents (p < .001). Overall, 53.1% of parents believe that the number of stateoffered vaccinations is influenced by economic interests of pharmaceutical companies.

Overall, 60.2% of parents consult the web for information on vaccinations, mainly generic searches on Google or other search engines (43.7%) and institutional websites (e.g., Ministry of Health, National Institute of Health, Italian Agency for Medicine) (43.1%). However, only 26.7% of parents ranked the web among the three main sources of information used. Only 32.6% of the sample considers the web a reliable source of information; this proportion is higher among anti-vaccine than pro-vaccine and hesitant parents. In contrast, over 90% of parents reported that their family paediatrician and other trusted physicians are a very or sufficiently reliable source of information on vaccinations.

The main factors associated with hesitancy were found to be: not having received from a paediatrician a recommendation to fully vaccinate their child [adjusted odds ratio (AOR): 3.21, 95% confidence interval (CI): 2.14-4.79], having received discordant opinions on vaccinations (AOR: 1.64, 95% CI: 1.11-2.43), having met parents of children who experienced serious adverse reactions (AOR: 1.49, 95% CI: 1.03-2.15), and mainly using non-traditional medical treatments (AOR: 2.05, 95% CI: 1.31-3.19).

The study found that hesitant parents' perceptions of the usefulness and benefits of vaccination is similar to that of pro-vaccine parents. Most hesitant parents think that very rare diseases could resurge if we stop vaccinating and that the whole community benefits from vaccination, suggesting that hesitant parents still consider vaccinations a valid tool for prevention. Thus, the researchers suggest that, in order to increase vaccine confidence, healthcare providers should provide univocal messages and information to parents. On the contrary, the study showed that 23% of parents who consulted more than one physician reported to have received discordant opinions. Considering that, similarly to pro-vaccine parents, hesitant parents report trusting their family paediatricians, physicians could benefit from appropriate communication interventions. As the researchers stress, training health professionals and providing homogenous information about vaccinations, in line with national recommendations, are crucial for responding to their concerns.