ABSTRACT
Background: Vaccinations are currently the key element in the prevention of the spread of infectious diseases. We studied parents’ opinions about mandatory and recommended preventive vaccinations in Poland.
Methods: A diagnostic survey using an original questionnaire was done in a group of 300 parents.
Results: A total of 3.7% of parents did not vaccinate their children. 90% were aware of the threat potentially posed by infectious diseases, and 73.7% knew that breastfeeding alone does not ensure sufficient protection against them. 28% believed that it is necessary to vaccinate a child against all diseases, 51.7% that the number of vaccinations is insufficient, and 62.7% that vaccine use is safe. 40.7% thought that unvaccinated children should not be able to attend nurseries and kindergartens, as they pose a threat to other children. Postvaccinal adverse events occurred in 21.3% of children, mainly (71.9%) an increase in body temperature above 38°C. 88.3% were informed about possible vaccine-induced complications, most often by nurses (79.7%). 88% of the respondents were aware of the possibility to switch to an alternative immunization program, 92% were informed on the possible administration of recommended vaccines, and 53% took advantage of combined vaccines.
Conclusions: Views on vaccinations were mostly varied, depending on the age, sex, education, and financial situation of the respondents. Most of the parents who did not vaccinate their children believed that immunity can be acquired by infection. They were in favor of a limited number of vaccinations, were more critical of the vaccination program in Poland, considered the vaccines used in Poland to be unsafe, and blamed vaccines for multiple developmental defects and autism in children. Parents whose children experienced vaccine-induced adverse reactions were more likely to have doubts before the next vaccination.
Introduction
Infectious diseases have been a major public-health problem since the dawn of time, due especially to the facts that numerous epidemics and pandemics have claimed many lives and humankind has faced high mortality due to infectious diseases (e.g., smallpox, yellow fever, plague, Spanish flu).Citation1 The use of vaccinations for more than 200 years has allowed us to control many dangerous diseases including smallpox, poliomyelitis, diphtheria, pertussis, and tetanus.Citation2
In Poland, the history of vaccination dates back to the beginning of the nineteenth century. The smallpox vaccine was the first to be introduced and was followed by vaccines against rabies and diphtheria initiated in the interwar period. In Poland, vaccination against chickenpox began in 1801–1802. In 1808, in Warsaw, the first Vaccination Institute against Smallpox was established and in 1811 this vaccination was mandatoryCitation1 .In 1886, in Warsaw, the Polish bacteriologist Odo Bujwid founded the Rabies Vaccination Institute. In Poland, Dzierzgowski conducted the first attempts to vaccinate against diphtheria in 1901. The first vaccination against tuberculosis BCG vaccine was carried out in 1926, and in 1956 it was introduced as mandatory vaccination.
Preventive vaccination programs have been modified and adjusted depending on the epidemiological situation in a given country and in accordance with the recommendations of the World Health Organization (WHO). In addition, vaccinations for travelers have been developed to protect travelers from serious diseases. Institutions supervising the implementation and safety of vaccinations (e.g., the National Institute of Hygiene) have been established. Together, these measures have resulted in a drop in mortality from infectious diseases from 20–25% in the first half of the 20th century to less than 1%.Citation2,Citation3
According to WHO, more than 22,000 cases of measles were reported in Kyrgyzstan, Bosnia and Herzegovina, Russia, Georgia, Germany, Kazakhstan, and Italy in 2014 and 2015.Citation4 Despite a 50% decrease in the number of new measles cases in 2014 compared to 2013, the disease continues to spread. In Ukraine, 1.5 million children under the age of 5 years have not been vaccinated against polio. The United Nations International Children’s Emergency Fund (UNICEF) has emphasized that immunizations prevent between two and three million deaths among children every year worldwide.Citation4
Vaccinations are currently the key element in the prevention of the spread of infectious diseases, enabling the protection of individuals as well as whole societies against diseases and allowing for the development of population immunity. Since the beginning of the 1990s, there has been a minor increase in the implementation of vaccinations worldwide, which is currently about 80% of people are vaccinated.Citation4 Most countries have a wide range of vaccinations protecting against more than 26 infectious diseases. The implementation of the universal mass vaccination program in Poland is regulated by law. The Polish Preventive Vaccination Program is an attachment to the annual announcement of the Chief Sanitary Inspector regarding preventive immunization against infectious diseases; it includes a list of mandatory and recommended vaccinations and is updated annually and adjusted for current epidemiological situations in the country as well as for the immunization status among children and adolescents.Citation5,Citation6 It is known that active prevention against infectious diseases is the most effective and, at the same time, the least expensive method for universal protection against these diseases; however, its efficacy is greatly affected by parental attitudes towards immunization programs implemented in a given population.Citation6 In Poland, vaccination coverage of children and adolescents is more than 95%. However, data from the National Institute of Public Health – National Institute of Hygiene indicate that about 3,000 parents refused to have their children vaccinated in 2011, and the number increased to 5.3 thousand in 2012, 7.2 thousand in 2013, and 12.7 thousand in March 2014.Citation7
There are recognized barriers affecting the implementation of childhood vaccinations. Esposito et al. described health system, provider, and parental barriers.Citation8 According to the authors, health system barriers to immunization include the costs of vaccines, difficulty of vaccine storage, reduced vaccine supply and distribution, and missed opportunities. The provider barriers to immunization include poor knowledge of immunization indications and contraindications, poor access to children’s immunization records, missed visits, and poor communication with parents and adolescents. Parental barriers to immunization comprise poor understanding of the real value of vaccines, fear of adverse events, and logistical and economic problems. Poor knowledge about the preventive effects of vaccinations is also a reason for avoiding compulsory immunization.
In recent years, anti-vaccine movements have intensified, and the number of parents refusing to vaccinate their children has increased, due primarily to a fear of vaccine-induced adverse reactions.Citation9 However, it should be emphasized that, although there are no vaccines that do not cause any adverse effects, the currently used vaccines are extremely safe, considering the complications related to the diseases they prevent.Citation10
The aim of the study was to learn about parents’ opinions of mandatory and recommended preventive immunizations in Białystok, Poland.
Results
Almost all surveyed parents (96.3%) declared that they vaccinated their children. A very small group of respondents (3.7%), who did not vaccinate their children, reported lack of conviction about vaccine efficacy, fear of complications, and negative information about vaccinations found on the Internet as the main reasons for their decision. Delayed vaccination of a child was reported in one in three families (33.7%). Disease at the time of immunization was the most common cause for delayed vaccination (87.1%). Other reasons were less common and included negative information about immunization (9.9%), serious disease preventing vaccination (4%), and malaise after the previous injection (3).
Only 8.3% of the respondents were convinced that no vaccine was safe. A subjective list of “safe vaccines” (not causing dangerous complications in the opinion of the parents) was also prepared. The vaccine against hepatitis B was ranked number one (29.3%), and was followed by vaccines against diphtheria, tetanus, pertussis (28%). Details are presented in .
Table 1. Safe and least safe vaccinations in the respondents’ opinions.
The majority of parents were not convinced that it is better to gain immunity by natural infection than by vaccination. There was a statistically significant (P = 0.0215) relationship between parental age and opinions on whether vaccines should be compulsory The older the parents reported more often that immunization should be compulsory. Parents aged 31–40 years significantly more often (P = 0.0005) used polyvalent vaccines. Details are shown in .
Table 2. Parents’ opinions on vaccinations, depending on their age.
In the next part of the study, we verified whether parental education affected their opinions on the vaccination of children. It was found that education did not differentiate the popularity of the view that experiencing all diseases is superior to vaccination. The surveyed parents with a vocational education significantly more often supported the view that vaccination against all diseases is necessary (64%, P = 0.0000). Respondents with a higher education were more skeptical about the current immunization program in Poland (it was supported by 52.1% of the parents from this group). Results are shown in .
Table 3. Parents’ opinions on vaccinations, depending on their education.
It was demonstrated that parental education had no impact on the opinion on whether vaccines used in Poland are safe. The higher the education of parents, had higher acceptance of voluntary immunization. Polyvalent vaccines were mainly used by the most educated parents (64.4%, P = 0.0005). Details are presented in .
In the next part of the study, it was found that parental sex was not a statistically significantly differentiating factor for views on preventive vaccination. A statistically significant difference (P = 0.0231) was shown in responses to questions regarding the use of recommended vaccines between parents of both sexes. Other results are shown in .
Table 4. Parents’ opinions on vaccinations, depending on their sex.
We also verified whether the financial status of parents influenced their knowledge and views on the vaccination of children.
In general, financial status had no influence on parents’ opinions on vaccinations. However, a higher proportion of parents in a better financial situation were of the opinion that the vaccines used in Poland are safe (P = 0.0230). Details are presented in .
Table 5. Parents’ opinions on vaccinations, depending on their financial situation.
Only 11 respondents (3.7%) in the evaluated group did not vaccinate their children. Despite its small size, the group was compared in terms of views with parents who did vaccinate their children. All respondents who did not vaccinate their children were definitely in favor of limiting the number of vaccinations. They were also more critical of the Polish vaccination program. Nearly all respondents (90.9%) reported that vaccines contain toxic compounds. Almost two-thirds of the opponents of vaccination (63.6%) blamed vaccines for a number of congenital defects in children, including autism. Details are shown in .
Table 6. Comparison of opinions on vaccinations between parents who vaccinate and do not vaccinate their children.
We also verified whether the occurrence of vaccination-induced adverse responses in children affected parents’ opinions. There was no influence of vaccination-induced side effects in children on parents’ opinions on vaccinations. Details are presented in .
Table 7. Parents’ opinions on vaccinations depending on the occurrence of vaccination-induced adverse reactions in their children.
presents the results of the analysis of the impacts of age, education and financial situation on selected opinions on the subject of vaccinations using logistic regression. The results of the logistic regression analysis allow for extension to the following applications among others. Despite the use of multifactorial data analysis techniques, no dependence of answers on level of education or financial situation could be found.
Table 8. Parents’ opinions on the subject of vaccination in relation to socioeconomic factors – the results of logistic regression analysis.
In the analyses performed, there were no statistically significant interactions between age, educational level, and material situation in the context of opinions on vaccinations.
There was a clear difference in the approach to the issue of mandatory immunization between people ages 18–30 and 41–50. In the group of youngest parents, relatively fewer people support compulsory preventive vaccinations (OR = 0.352). The use of combination vaccines was dependent on age and education. The use of this type of vaccine is negatively affected by a lower level of education (high school vs. university: OR = 0.372). The performance of additional vaccinations depended only on the parents’ education.
Discussion
The value of vaccination, as one of the methods of protecting against infectious diseases, is undeniable. This fact should be emphasized in the education of society, particularly in the context of the growing number of mandatory vaccination refusals among children and adolescents.
In our survey, almost all parents (96.3%) declared that they vaccinated their children. However, we found different opinions on vaccinations among parents. Parents’ attitudes toward vaccination depended on the age, sex, education and financial situation of the respondents. Our findings are in accordance with previous studies from Poland and other countriesCitation11–Citation18. Most of the parents who did not vaccinate their children believed that immunity can be acquired by natural infection. They reported also that vaccines used in Poland to be unsafe, and blamed vaccines for multiple developmental defects and autism in children.
In the Polish study, Świątoniowska and RozensztrauchCitation11 showed that 85.3% of parents reported that vaccines are safe. Also, Pieszka et al.,Citation12 found that 96% parents considering vaccines to be safe, while Gawlik et al.,Citation14 showed that 61% parents considered vaccines to be safe. In a study from CanadaCitation19, 94% of parents agreed that recommended vaccines are important (94%) and useful (94%) for children’s health. In a study from USA,Citation17 more than 90% of the mothers reported belief that vaccines are necessary to prevent certain diseases. Our study showed that 96.3% of the parents vaccinated their children and 62.7% considered vaccines safe.
Fear of illness in the child was the most important factor affecting the decision regarding vaccination among the mothers in previous studiesCitation9,Citation12,Citation13,Citation17. Similarly, our study showed that 91% of the parents vaccinated their children for the sake of their health.
In the study by LeszczeynskaCitation13 43% of respondents opted for recommended vaccines, mainly against pneumococci (68%) and meningococcal disease (54%). Similarly, in our study, recommended vaccines, mainly against pneumococci were used by 53% of respondents.
Świątoniowska and RozensztrauchCitation11 showed a statistically significant relationship between respondent age and their attitudes towards vaccinations, with younger respondents being more in favor of vaccination compared with older individuals. Our study also showed that the conviction about the need for mandatory vaccinations was more common among older parents.
Variables such as maternal education and economic status, have been shown to influence children vaccinations in many countriesCitation12,Citation17–Citation19. However, in our study, education level had no effect on children immunization.
Parents usually chose polyvalent vaccines due to the lower number of injections, and thus reduced pain, whereas they refused to use these preparations due to lack of knowledge or high priceCitation20. In our study, 53% of respondents used polyvalent vaccines, usually motivated by the lower number of injections (91.8%) and the conviction that they are safe (35.8%).
Vaccine-induced adverse reactions occur infrequently.Citation21. The frequency of adverse events following BCG vaccination in Poland oscillated within 1994–2000 and 2001–2010 periods around 0.2 per thousand and 0.6 per thousand respectively, and in half consisted of local lesions at the injection sites and in half–appeared in the form of the regional lymphadenopathy.
Parents have usually concerns about vaccine-induced adverse reactions, including fever, convulsions, and autismCitation11,Citation12,Citation16. In our study, vaccine-induced adverse reactions occurred in 21.3% of the children and mainly included increased body temperature above 38°C (71.9%) and reddening/edema at the injection site (51.6%).
Family doctors and nurses are common source of knowledge about vaccinations in previous manyCitation12–Citation14,Citation16,Citation17, and our study too.
Parents’ knowledge about vaccination have influence on the positive decisions concerning recommended vaccination of their childrenCitation12,Citation17,Citation22–Citation25. In our survey, the group of parents who did not vaccinate their children found negative information about vaccines on the Internet.
Although coverage levels for most childhood vaccines remain high in Poland (95%) and Europe. In our survey, only 3.7% parents did not vaccinate their children. However, numerous studies have documented that vaccine-related confidence has been decreasing among parents over the past several yearsCitation26–Citation28. Vaccine hesitancy is an critical issue to be addressed, due to the risk of decrease of vaccination coverage and indirect control of preventable diseases. According to Biasio et al.Citation29, poor or inadequate communication is a specific determinant, it can contribute to vaccine hesitancy and negatively influence vaccination uptake.
The importance of healthcare providers’ communication abilities is still underestimated. Informing the people by documented evidence is essential but not enough to induce a change in the beliefs of who is doubtful or does not accept preventive interventions, such as vaccinationCitation30.
In a recent cross-sectional multicentre study, Gualano et. Citation31 in 1820 pregnant women from Italy assessed the interviewee’s opinion on mandatory vaccines. The authors found that information sources play a crucial role in determining the opinion on the restoration of mandatory vaccines. Women who obtained information from anti-vaccination movements were less likely to accept the vaccines. Women who had confidence in healthcare professional information agreed more on mandatory vaccination than did the other women.
The reason for the resignation from compulsory vaccinations is the low level of parents’ knowledge about the protective effect of vaccines and the anti-vaccine movement, which is becoming more and more integrated from year to year. Therefore, regular monitoring of parents’ attitudes to the vaccination program and vaccines in Poland is essential, which will allow for the ongoing adaptation of educational programs to current needs. Universal access to such information, on the one hand, will facilitate the acquisition of reliable knowledge, but at the same time allows contact with information not fully proven and with the activity of anti-vaccine movements. Reliable information about vaccinations should not be transmitted only during the first vaccination visit, but also raised during subsequent meetings, not only regarding mandatory and recommended vaccinations.
Our study has several limitations. First, the sample size of our study is too small to draw more general conclusions. Second, we used the original questionnaire so it is impossible to compare our results with other studies. Third, women constituted the majority of respondents – 83% and the similar percentage of the respondents were urban residents. Fourth, respondents had different education and economic status.
Conclusions
Views on vaccinations were mostly varied, depending on the age, sex, education, and financial situation of the respondents. The parents who did not vaccinate their children believed that immunity can be acquired by natural infection. They were in favor of a limited number of vaccinations, were more critical of the vaccination program in Poland, considered the vaccines used in Poland to be unsafe, and blamed vaccines for multiple developmental defects and autism in children. Parents whose children experienced vaccine-induced adverse reactions were more likely to have doubts before the next vaccination.
Methods
The study was conducted between July 2015 and June 2016, after obtaining the approval of the Bioethics Committee of the Medical University in Białystok, Poland (R-I-002/196/2015) and the consent of the authority of the Pro Medica Family Medicine Center in Białystok, Poland.
A diagnostic survey using an original questionnaire was performed. We did not include any questions collecting identifiable data. The tool was subject to basic standardization (pilot study).
Data analysis
Statistical analysis was conducted by Marek Sobolewski, PhD, from the Department of Quantitative Methods in Economics at the Faculty of Management and Marketing at Rzeszów University of Technology, Poland. Data management was performed in Statistica 13 (Statsoft, TULSA, OK, USA). Relationships between the two variables were analyzed using the chi-square independence test. The relationships between the three groups () were examined using the Kruskal-Wallis test. In this study, we applied logistic regression. For the purposes of logistic regression analysis, the answers to the considered vaccination questions have been dichotomized, combining the “do not know” category with the “yes” or “no” categories, depending on the nature of the question. As independent variables, the educational level, material status and age of parents as well as the interaction of the second degree between these factors were introduced. The results were presented only for factors that were statistically significant; their selection was made using the progressive stepwise regression procedure. The critical level for all tests of significance was p < 0.05.
The questionnaires were given to the parents attending with children to the visits to the Pro Medica Family Medicine Centre” in Bialystok. Of the 350 questionnaires distributed 300 were suitable completed, the return rate was 85.7%
The study included 300 parents attending the Pro Medica Family Medicine Center in Białystok. A total of 46.3% of the respondents were aged between 31 and 40 years, 30% between 18 and 30 years, and 23.7% 41 and 50 years. Women accounted for 83% and men for 17% of the respondents. A total of 84% of the respondents were urban residents, while 16% were from rural areas. Higher education was declared by 54.3%, secondary education by 37.3%, vocational education by 7.3%, and primary education by 1% of the respondents. Most respondents (57.3%) declared that their financial situation was good. An average, very good, and poor financial situation was declared by 31%, 10%, and 1.7% of the respondents, respectively. The vast majority of the surveyed parents (85%) were not professionally connected with health care. Only 15% of the respondents were in the medical profession.
Disclosure of potential conflicts of interest
No potential conflicts of interest were disclosed.
Additional information
Funding
Notes on contributors
Wojciech Kułak
JK, EKK, KK, MC, AG, BK, BJ, and HR, HD, and WK were involved in the study. JK EKK, and KK undertook the analyses. All authors were involved in developing the manuscript and approved the final version for submission.
References
- Rudkowski Z. Ważniejsze zdarzenia w historii szczepień przeciwko chorobom zakaźnym. Stand Med Lek Pediatr. 2002;4:480–486. [Polish].
- Plotkin S. History of vaccination. Proc Natl Acad Sci USA. 2014;111(34):12283–12287. doi:10.1073/pnas.1400472111.
- Helfert SM. Historical aspects of immunization and vaccine safety communication. Curr Drug Saf. 2015;10(1):5–8.
- WHO calls for more measles vaccination in Europe as large outbreaks persist. [ accessed 2017 Dec 10]. https://www.reuters.com/article/us-health-measles-europe/who-calls-for-more-measles-vaccination-in-europe-as-large-outbreaks-persist-idUSKBN0LT14320150225.
- Gawłowska-Lichota K, Płatek M. Analysis of children’s vaccinations with selected vaccines at the health care center in Polanów in 2004-2008. Probl Pielęg. 2011;19:34–38. [Polish].
- Gładysz A, Rymer W, Inglot M, Rotter K, Knysz B. Vaccination programs in Poland. Przegl Epidemiol. 2004;58 Suppl 1:80–89. [Polish].
- The National Institute of Public Health – National Institute of Hygiene (NIPH – NIH). [ accessed 2017 Dec 11]. http://www.pzh.gov.pl/.
- Esposito S, Principi N, Cornaglia G. ESCMID vaccine study group (EVASG). Barriers to the vaccination of children and adolescents and possible solutions. Clin Microbiol Infect. 2014.;Suppl 5:25–31. doi:10.1111/1469-0691.12447.
- Dubé E, Vivion M, MacDonald NE. Vaccine hesitancy, vaccine refusal and the anti-vaccine movement: influence, impact and implications. Expert Rev Vaccines. 2015;14(1):99–117. doi:10.1586/14760584.2015.964212.
- Robertson CA. The science of vaccination: establishing safety and efficacy. DS Med. 2013;Spec no:38-45.
- Świątoniowska N, Rozensztrauch A. Vaccinations through the mothers eyes. J Educ Health Sport. 2017;7(8):11–19.
- Pieszka M, Waksmańska W, Woś H. Wiedza rodziców dzieci do drugiego roku życia na temat szczepień ochronnych. Med Ogólna Nauk Zdrow. 2016;22(2):221–226.
- Leszczyńska E, Borkowska E, Irzyniec T, Pałka I, Satwicka K, Mazurek M, Podsiadło B. Postawa rodziców wobec szczepień ochronnych. In: Markocka K, Mączka KH, editors. Dobrostan a rozwój i zdrowie dzieci i młodzieży. Lublin (Poland): Wydawnictwo Naukowe NeuroCentrum; 2016. p. 157–170. [Polish].
- Gawlik K, Woś H, Waksymańska W, Łukasik R. Opinie rodziców na temat szczepień ochronnych u dzieci. Med Ogólna Nauk Zdrow. 2014;20(2):360–364. [Polish]. doi:10.5604/20834543.1132036.
- Kata A. Anti-vaccine activists, Web 2.0, and the postmodern paradigm—an overview of tactics and tropes used online by the anti-vaccination movement. Vaccine. 2012;30(25):3778–3789. doi:10.1016/j.vaccine.2011.11.
- Faleńczyk K, Piekarska M, Pluta A, Basińska H. Czynniki wpływające na postawy rodziców wobec szczepień ochronnych u dzieci. Postęp Nauk Med. 2016;6:380–385. [Polish]. doi:10.5604/08606196.1205281.
- Vannice KS, Salmon DA, Shui I, Omer SB, Kissner J, Edwards KM, Sparks R, Dekker CL, Klein NP, Gust DA. Attitudes and beliefs of parents concerned about vaccines: impact of timing of immunization information. Pediatrics. 2011;127(Suppl 1):S120–126. doi:10.1542/peds.2010-1722R.
- Rammohan A, Awofeso N, Fernandez RC. Paternal education status significantly influences infants’ measles vaccination uptake, independent of maternal education status. BMC Public Health. 2012. 12:336. doi:10.1186/1471-2458-12-336.
- Dubé E, De Wals P, Gilca V, Boulianne N, Ouakki M, Lavoie F, Bradet R. New vaccines offering a larger spectrum of protection against acute otitis media: will parents be willing to have their children immunized? Int J Pediatr Otorhinolaryngol. 2009;73(7):981–987. doi:10.1016/j.ijporl.2009.03.022.
- Lipska E, Lewińska M, Górnicka G. Recommended vaccinations among children and parents’ opinions on vaccinations. Nowa Med. 2013;2:43–48. [Polish].
- Fredrickson DD, Davis TC, Arnould CL, Kennen EM, Hurniston SG, Cross JT, Bocchini JA Jr. Childhood immunization refusal: provider and parent perceptions. Fam Med. 36;2004:431–439.
- Thorpe EL, Zimmerman RK, Steinhart JD, Lewis KN, Michaels MG. Homeschooling parents’ practices and beliefs about childhood immunizations. Vaccine. 2012. 30:1149–1153. doi:10.1016/j.vaccine.2011.12.019.
- Nitsch-Osuch A, Kozerska A, Topczewska-Cabanek A, Życińska K, Wardyn K. Realization of immunization schedule with recommended vaccines among children from one general practice. Fam Med & Prim Care Rev. 14;2012:410–413.
- Perception of vaccinations associated with mothers of infants and pregnant women. [ accessed 2017 Dec 14]. PL/VAC/0014/16, https://pl.gsk.com/media/679363/mb-gskkonferencjaskojarzone-10-06.pdf.
- Krysztopa-Grzybowska K, Paradowska-Stankiewicz I, Lutyńska A. The rate of adverse events following BCG vaccination in Poland. Przegl Epidemiol. 66;2012:465–469.
- Gowda C, Dempsey AF. The rise (and fall?) of parental vaccine hesitancy. Hum Vaccin Immunother. 2013. 9:1755–1762. doi:10.4161/hv.25085.
- Dubé E, Gagnon D, Nickels E, Jeram S, Schuster M. Mapping vaccines hesitancy–country-specific characteristics of a global phenomenon. Vaccine. 2014. 32:6649–6654. doi:10.1016/j.vaccine.2014.09.039.
- Salmon DA, Dudley MZ, Glanz JM, Omer SB. Vaccine hesitancy: causes, consequences, and a call to action. Am J Prev Med. 2015;49(6 Suppl 4):S391–8. doi:10.1016/j.amepre.2015.06.009.
- Biasio LR, Corsello G, Costantino C, Fara GM, Giammanco G, Signorelli C, Vecchio D, Vitale F. Communication about vaccination: a shared responsibility. Hum Vaccin Immunother. 2016;12(11):2984–2987. doi:10.1080/21645515.2016.1198456.
- Biasio LR, Carducci A, Fara GM, Giammanco G, Lopalco PL. Health literacy, emotionality, scientific evidence: elements of an effective communication in public health. Hum Vaccin Immunother. 30;2018:1–2.
- Gualano MR, Bert F, Voglino G, Buttinelli E, Mm D, De Waure C, Di Giovanni P, Mp F, Ar G, Marranzano M, et al. Attitudes towards compulsory vaccination in Italy: results from the NAVIDAD multicentre study. Vaccine. 2018;36(23):3368–3374. doi:10.1016/j.vaccine.2018.04.029.