ABSTRACT
Vaccine hesitancy and refusal threaten to reverse progress made in tackling vaccine-preventable diseases. This problem is not new, and gaining an increasing importance due to the increase in its incidence. The present study aims to determine the frequency of factors related to vaccine hesitancy and refusal among parents of children under five.
A community-based study was conducted with 402 parents of children under five in a province of Turkey between October 2020 and February 2021. The number of samples to be included in the study was determined by proportional cluster sampling. Data were collected using the WHO SAGE “Vaccine Hesitancy Survey Questions” and “Vaccine Hesitancy Scale”.
Of parents, 19.7% were hesitant about childhood vaccines. The rejection rate of recommended vaccines (special or free vaccines) was 18.2%. The rate of parents who refused the vaccines offered free of charge by the Ministry of Health was 0.9%. Vaccine hesitancy was higher among fathers, those with undergraduate and higher education, parents over 42 years of age, and those with a higher income economic status. Having heard or read negative information about vaccines increased the likelihood of vaccine hesitancy by 13.5 times. The parents’ Vaccine Hesitancy Scale score was 1.68±0.53.
According to the study results, vaccine hesitancy and refusal have a structure affected by many factors. The most important of these factors is the content of knowledge about vaccines.
Introduction
Immunization is one of the most successful and cost-effective health interventions worldwide (1). Despite the proven success in saving the lives of millions of children and preventing diseases and disabilities every year, vaccine hesitancy and refusal have been increasingly on the agenda in recent years. Vaccine hesitancy and refusal threaten to reverse progress made in tackling vaccine-preventable diseases (2).
Vaccine hesitancy is defined as the delay or refusal to accept vaccines despite the availability of vaccination services. Individuals who are hesitant about vaccination may accept all vaccinations but continue to be concerned about vaccinations. Some people may reject or delay some vaccines while accepting other vaccines. Some individuals may also refuse all vaccines (3,4). Therefore, vaccine hesitancy may cause people to refuse the vaccine by affecting their motivation to vaccinate themselves or their children. According to the results of the analysis of the three-year data available in the Joint Report Form in 2017, which was prepared by the WHO and UNICEF (United Nations International Children’s Emergency Fund) to reveal global vaccine hesitancy and its change over the years, vaccine hesitancy was reported in more than ninety percent of 184 countries. Furthermore, it was observed for three years that most reasons stated for vaccine hesitancy were not based on an evaluation but opinion. As a result of the evaluation, the rate of countries stating reasons for vaccine hesitancy was only 38% (5).
Considering that vaccine hesitancy among parents of children under five may result in vaccine refusal, it is necessary to know the frequency of vaccine hesitancy in society, question the concerns and reasons of those who are hesitant, and understand what increases their hesitancy. The success of health services depends on the cooperation and full participation of individuals in that community. Therefore, it is of great importance for public health services to evaluate vaccine hesitancy in society with appropriate measurement tools.
This study aims to determine the frequency of vaccine hesitancy and refusal among parents of children under five and the factors associated with them.
Materials and Methods
The presents research is a descriptive cross-sectional study. A community-based study was conducted with 402 parents of children under five in province Tokat of Turkey between November 2020 and January 2021. The current study was approved by Başkent University Non-Interventional Clinical Research Ethics Committee (Project no: KA20/332) and supported by Başkent University Research Fund. Furthermore, institutional permission was received from the Provincial Governor’s Office with the letter numbered 20286032-492-E.6166 on 30.07.2020 to carry out the fieldwork.
Sampling and Study Procedure
The sample size of the study was calculated as 402 parents of children under five, by considering at least a 95% confidence interval, 0.05 deviation, and 20% loss rate, using the Open Epi program (6). Intensive vaccination is carried out in the first five years of life to protect children from vaccine-preventable infectious diseases. Vaccine hesitancy among parents of children under five adversely affects vaccine acceptance. Therefore, this study was conducted on parents of children under five. Sample selection was made in two stages. At the first stage, the proportional cluster sampling method was employed to determine the number of parents to be included in the study in the neighborhoods of the city center (7). There are 42 neighborhoods affiliated with the municipality in the city center. Each neighborhood was taken as a cluster, and the number of samples to fall into each cluster was calculated proportionally according to the cluster weight. At the second stage, a household with children under five was randomly selected as the starting point in each neighborhood with purposive sampling. Participants must be over the age of 18 and have children under five to participate in the study. If a child had a chronic disease or was born prematurely and was of a foreign nationality, we did not include the parents of these children in the study. Only one parent in a household who had a child under five and volunteered to participate in the study was interviewed, and priority was given to interviewing mothers. If there was more than one child under five in a household, parents were asked to answer the survey questions considering the child with the youngest age in months.
Data Collection
The “Vaccine Hesitancy Survey Questions (VHSQ)” and “Vaccine Hesitancy Scale (VHS)” developed by the WHO SAGE Vaccine Hesitancy Working Group were used as data collection tools. One more descriptive survey created by the researchers was done to obtain information about the family. Permission was received from Heidi J. Larson on behalf of the SAGE Vaccine Hesitancy Working Group who developed the questionnaire and scale to use the VHSQ and VHS (8). The VHSQ consists of 11 closed and open-ended questions, including parents’ hesitations, rejections, and opinions about childhood vaccinations. The VHS consists of a five-point Likert-type scale containing 10 propositions about vaccines: 1= strongly disagree, 2= disagree, 3= neither agree nor disagree, 4= agree, and 5= strongly agree. The VHS was developed by Larson et al. (8) in 2015, whereas Shapiro et al. (9) tested its validity and reliability. Prior to this research, the researchers conducted the validity and reliability study of the VHS. According to the research results, a structure consisting of 7 items (L1-L4 and L6-L8) with a single factor was valid and reliable. Cronbach’s α value was 0.83 (10).
Statistical Analysis
As descriptive statistics, quantitative data were expressed as mean (M) and standard deviation (SD), and qualitative data were presented as number (n) and percentage (%). Pearson’s chi-squared test or Fisher’s Exact test was used in 2x2 crosstabs to compare qualitative data, while Pearson’s chi-squared test was used in r x c crosstabs. Multivariate logistic regression analysis was conducted to determine the risk factors influencing vaccine hesitancy.
Whether the research sample represented the universe according to some characteristics (mother’s age group, child’s gender, and child’s age group) was evaluated with the one-sample t-test for universe ratio. According to the analysis results, the research sample represented the universe and showed similarities with Turkey. Statistical analyses were conducted in SPSS (Statistical Package for Social Sciences) for Windows 20.0 program. The value of p<0.05 was considered significant.
Results
Of the interviewed parents, 389 (96.8%) were mothers, and 13 (3.2%) were fathers. The parents’ socio-demographic characteristics are summarized in Table 1.
While 19.7% of the interviewed parents were hesitant to vaccinate their children, the rate of those who rejected at least one of the vaccines (private and free vaccines) recommended for their children was 18.2% (Table 2). Among the vaccines about which parents were hesitant (n=79), the highest hesitancy of 83.5% was experienced in the measles, mumps, and rubella (MMR) vaccine. Among the rejected vaccines (n=73), the MMR vaccine was the most rejected among free vaccines at a rate of 5.5%, while the rotavirus vaccine was the most rejected among paid vaccines at a rate of 98.6%.
Of the participants, 33.6% had negative information about vaccines, and among the negative information obtained, it was mostly reported that the vaccine was harmful at a rate of 53.4%. The number of the participants who took their children to vaccination after receiving negative information was 96.3% (Table 3).
Vaccine hesitancy was higher among fathers, those with undergraduate and higher education, parents over 42 years of age, and those with a higher income economic status. Vaccine refusal was higher among fathers and parents with undergraduate or higher education (p<0.05) (Table 4).
Among the interviewed parents, fathers were 11.79 times more likely to experience vaccine hesitancy than mothers [OR=11.79, (95% CI=2.01-60.12)]. Having heard or read negative information about vaccines increased the risk of vaccine hesitancy by 13.58 times [OR=13.58, (95% CI=6.55-28.13)] (Table 5).
In the responses of the participants to the WHO SAGE VHS items, it was seen that they agreed with the statement “Getting vaccinated is a good way to protect my child from the disease” and “I usually follow the recommendations of my doctor or healthcare professional regarding vaccinations for my child” (Figure 1).
Upon examining the VHS mean score of the interviewed parents, the mean score of vaccine insecurity, the general structure (items L1-L4, L6-L8) of the scale, was 1.86±0.53 (It is reverse coded according to the original range of the scale). A low score on the WHO SAGE VHS indicates a low level of vaccine hesitancy, while a high score indicates a high level of vaccine hesitancy. According to the scale’s general structure, the vaccine hesitancy level of the participants was low. Furthermore, Cronbach’s α value was 0.92 in the data set of 398 participants [Those (n=4) who refuse free vaccines offered by the Ministry of Health are excluded]. The highest mean score among the items (L5, L9, and L10) removed in the confirmatory factor analysis was 3.01±1.01, and L9 was “Concerns about side effects”. Item L5 (New vaccines risky) was mean of score 2.68±0.65. Item L10 (Some vaccines no longer needed) was mean of score 2.53±0.79 (Table 6).
Discussion
Vaccine hesitancy and refusal are public health problems affected by many complex factors, are not new, and are gaining increasing importance due to the increase in their incidence. Therefore, the WHO recommends that the factors triggering vaccine hesitancy and refusal in countries’ environments should be evaluated with appropriate measurement tools (5). This is the first community-based study in Turkey conducted on parents of children under five, using the VHSQ and the VHS developed by the WHO SAGE.
While 19.7% of the parents interviewed in this study were hesitant to have their children vaccinated, the rate of those who refused at least one of the recommended vaccines (private or free vaccines) was 18.2%. In studies conducted in Italy, vaccine hesitancy rates ranged from 15.6% to 24.6% (11-13). In the study by Dube et al. (14) the rate of vaccine hesitancy in Canada was 16.1%. In the study conducted by Migriño et al. (15) in the Philippines, 31% of the parents were hesitant about vaccination, while 23.7% refused at least one vaccine. The vaccine hesitancy rate was 83% in the study carried out by Dasgupta et al. (16) in India. The results of some studies conducted on parents of children under five are similar to those obtained in our study. Many studies have shown that the incidence of vaccine hesitancy and refusal varies because there are numerous factors affecting vaccine hesitancy and refusal. For example, since a new vaccine was added to the vaccine program during the study conducted in India, the rate of vaccine hesitancy may have been high (16).
In the present study, the vaccine about which parents were hesitant the most was the MMR vaccine (83.5%), while the most rejected vaccine was the MMR vaccine (5.5%) among free vaccines and the rotavirus vaccine (98.6%) among paid vaccines. In the study conducted by Campbell et al. (17) in England, parents rejected influenza and MMR vaccines most frequently. A study by Taiwo et al. (18) showed that the most widely rejected vaccine was the polio vaccine. The highest rejection rate for the rotavirus vaccine among private vaccines can be explained by parents’ financial difficulties and not regarding it as necessary. On the other hand, historical events increase vaccine hesitancy and refusal, e.g., the Trovan case in Nigeria in 1996. Considering the reasons for vaccine hesitancy and refusal in the current study, not regarding the vaccine as necessary, insecurity/side effects of the vaccine, and hearing/reading negative news in the media are the first three leading causes. Miko et al. (19) found the reason for vaccine hesitancy as negative news in the media. However, in our study, not regarding the vaccine as “necessary” was the main reason because people who refuse the vaccine are also those who refuse special childhood vaccines. Therefore, this situation originates from the fact that, as stated by parents, “if it was very necessary and compulsory, the state would have done it anyway.”
The interviewed parents answered “yes” to the question, “Do you think that most of the parents like you have their children get all the recommended vaccines?” at a rate of 70.9%. In studies conducted using the VHSQ in different countries, this rate varies between 40.8% and 84.6% (16,20).
In the study, fathers were more hesitant about vaccination than mothers at a statistically significant level. The results obtained by Ren et al. (20) and Giambi et al. (11) are similar to those obtained in this study. In contrast, in a study by Campell et al. (17) mothers were more likely to delay and reject a vaccine than fathers. The lowest vaccine hesitancy rate among the participants was in the age group of 18-25, while the highest hesitancy rate was in the age group of 42 years and older. Contrary to our study, Brown et al. (21) found that a high parental age was associated with high vaccine confidence.
Among the parents, those with undergraduate or higher education were more likely to experience vaccine hesitancy. Likewise, in a study by Giambi et al. (11) vaccine hesitancy was higher in those with university or higher education. On the other hand, some studies indicate high vaccine hesitancy in individuals with low parental education (16,22). The SAGE Vaccine Hesitancy Working Group reports that education level can both encourage and hinder vaccine acceptance, depending on current circumstances (23).
In this study, vaccine hesitancy was higher among parents with a higher income. The study findings obtained by Dasgupta et al. (16) and Özceylan et al. (24) support our results. A study by Migriño et al. (15) found that parental income was not associated with vaccine refusal. According to these results, vaccine hesitancy and refusal are not only a problem in high-income countries, but they also have a complex structure that can be seen in middle and low-income countries (25).
Vaccine hesitancy and refusal may develop in individuals who develop side effects after vaccination (3). In a study conducted in Italy, encountering parents whose children developed serious side effects after vaccination was identified as one of the main factors associated with vaccine hesitancy (11). In our study, in line with the literature, each unit increase in post-vaccine side effects in the participants’ children increased the risk of vaccine hesitancy by 1.9 times.
In the present study, the parents who did not believe that vaccines would protect their children from serious diseases were 4.6 times more hesitant to get vaccination than those who believed. Similar to the findings of our study, there are studies in which this rate is low in both high vaccine hesitancy and high vaccine refusal (15,26). In our study, hearing or reading negative information about vaccines by parents increased the probability of vaccine hesitancy by 13.5 times, and vaccine refusal was high. In a study by Giambi et al. (11), obtaining negative information about vaccines in the media resulted in parents rejecting at least one vaccine. Khattak et al. (26) found vaccine refusal to be higher in parents who heard and read negative information about the vaccine. Hearing and reading negative information about the vaccine increase vaccine hesitancy and refusal, which can be explained by the fact that parents who receive negative information about the vaccine tend to be more sensitive to media news, whether confirmed or not, and often refer to the internet as a source of vaccine information.
In the VHS items, most participants agreed on the importance of the vaccine, its effectiveness, and its benefits for society. The parents’ VHS score in this study was 1.68±0.53, which is similar to that in the study by Wagner et al. (27) conducted in five countries.
Conclusion
As a result, approximately one-fifth of parents of children under five experience vaccine hesitancy or refusal. The most important factor in parents’ vaccine hesitancy and refusal is negative information about childhood vaccinations. Therefore, more comprehensive and regular research should be done using the VHSQ and VHS in order to determine these factors in society. To overcome vaccine hesitancy and refusal, appropriate strategies should be determined in light of scientific data.
Acknowledgment: We would like to thank all the parents who participated in the study.
Ethics
Ethics Committee Approval: This study was approved by Başkent University Non-Interventional Clinical Research Ethics Committee (project no: KA20/332).
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: Supported by Başkent University Research Fund (project no: KA20/332). Başkent University funded the ethical approval of the study.
