The Influence of Introducing Free Vaccination against Streptococcus pneumoniae on the Uptake of Recommended Vaccination in Poland.

Since 2017, pneumococcal vaccination has evolved from a recommended chargeable vaccination to a mandatory, and therefore free, vaccination for all children. While a 10-valent vaccine is commonly used, parents have the option to use a 13-valent vaccine for a fee. This study aimed to investigate whether and how the introduction of free pneumococcal vaccination affected the uptake of recommended vaccination and to assess the association of chargeable pneumococcal vaccination with recommended vaccination. Data from 1595 vaccination record cards kept by six primary care clinics in urban and rural areas of Poland were collected and analyzed for children born between 2015 and 2018. Belonging to the clinic and the year of birth were the only inclusion criteria. Following the introduction of free universal pneumococcal vaccination, more children were vaccinated with the recommended vaccination (61.2% vs. 66.6%, p = 0.026). The most significant change was in vaccination against rotavirus (48.5% vs. 54.4%, p = 0.018) and against meningococcal B bacteria (4.8% vs. 17.0%, p < 0.001). Children who received chargeable pneumococcal vaccination were also significantly more likely to be vaccinated with recommended vaccines (54.6% vs. 75.9%, p < 0.001). In particular, this was the case for multivalent vaccinations-against rotavirus, chickenpox, and meningococcal C bacteria. Reducing the impact of the economic factor, for example, by introducing free vaccinations, should have a positive impact on the uptake of other recommended vaccinations.

Previous Vaccination History and Psychological Factors as Significant Predictors of Willingness to Receive Mpox Vaccination and a Favorable Attitude towards Compulsory Vaccination.

During the ongoing multi-country monkeypox (Mpox) outbreak, healthcare workers (HCWs) have represented a key group in mitigating disease spread. The current study aimed to evaluate the attitude of nurses and physicians in Jordan towards Mpox vaccination, as well as their attitude towards compulsory vaccination against coronavirus disease 2019 (COVID-19), influenza, and Mpox. An online survey was distributed in January 2023 based on the previously validated 5C scale for psychological determinants of vaccination. Previous vaccination behavior was assessed by inquiring about the history of getting the primary and booster COVID-19 vaccination, influenza vaccine uptake during COVID-19, and any history of influenza vaccine uptake. The study sample consisted of 495 respondents: nurses (n = 302, 61.0%) and physicians (n = 193, 39.0%). Four hundred and thirty respondents (86.9%) had heard of Mpox before the study, and formed the final sample considered for Mpox knowledge analysis. Deficiencies in Mpox knowledge were reflected in a mean knowledge score of 13.3 ± 2.7 (out of 20.0 as the maximum score), with significantly lower knowledge among nurses and females. The intention to receive Mpox vaccination was reported by 28.9% of the participants (n = 143), while 33.3% were hesitant (n = 165), and 37.8% were resistant (n = 187). In multivariate analysis, Mpox vaccine acceptance was significantly associated with previous vaccination behavior, reflected in higher vaccine uptake and with higher 5C scores, while Mpox knowledge was not correlated with Mpox vaccination intention. The overall attitude towards compulsory vaccination was neutral, while a favorable attitude towards compulsory vaccination was associated with higher 5C scores and a history of previous vaccination uptake. The current study showed a low intention to get Mpox vaccination in a sample of nurses and physicians practicing in Jordan. The psychological factors and previous vaccination behavior appeared as the most significant determinants of Mpox vaccine acceptance and of attitudes towards compulsory vaccination. The consideration of these factors is central to policies and strategies aiming to promote vaccination among health professionals in efforts to prepare for future infectious disease epidemics.

Perception of low social pressure and lack of capacity reduces vaccination compliance - The case of lumpy skin disease.

Successful prevention of epidemics depends on implementation of control measures, including vaccine compliance and maintenance of high vaccination coverage for long periods. However, to the best of our knowledge, a study of the temporal dynamics of compliance in voluntary vaccination campaigns and of the factors which influence them was never published. In this study, we investigated the factors influencing the dynamics of vaccination compliance against lumpy skin disease (LSD) after the occurrence of LSD epidemics in Israel in 2012-2013 and 2019. From 2016 to 2019, we followed voluntary LSD annual vaccination among a cohort of 566 farmers and used questionnaires based on the theory of planned behaviour to investigate the incentives influencing vaccine compliance among 90 farmers. The results showed a reduction in vaccination against LSD from 61% in 2016 to 27% in 2019 and a very strong association between prior vaccination and vaccination compliance. The actual vaccination by farmers who stated a positive intention to vaccinate was 4.5 times higher than farmers who did not (p-value = .007). However, half of the highly intended farmers eventually did not vaccinate their herd. These farmers were significantly more concerned by manpower and vaccine price compared to their vaccinating counterparts, pointing to vaccination effort perceptions as a major factor influencing compliance. In addition, we found that farmers who answered the questionnaires before the LSD epidemic of 2019 perceived significantly less pressure to vaccinate imposed by veterinary organizations (private and governmental) than farmers answering them during or after the epidemic. We conclude that the veterinarian-associated social pressure is a major compliance-enhancing factor, influenced by the occurrence of an epidemic. Our findings suggest that the deterioration of vaccination compliance after an epidemic can be mitigated by maintenance of pressure to vaccinate by veterinarians. Manpower support and vaccine discounts may be advocated to promote vaccine compliance.

Association between health and safety perceptions of COVID-19 vaccine and its uptake in Ghana.

Background: Attitudes towards vaccines have affected COVID-19 vaccination programs in many countries. This study sought to evaluate the effects of general perceptions on the safety and health concerns and the confidence in COVID-19 vaccines on its uptake in Ghana. Methods: A cross-sectional online survey was conducted between January and March 2021. The outcome variables for this study were "Taking mandatory COVID-19 vaccine" and "Taking voluntary COVID-19 vaccine". The data were subjected to both descriptive (frequency, percentages, and chi-square tests) and inferential (complementary log-log logistic regression) analyses. Results: Out of 620 Ghanians who participated in the survey, about 80% of the participants believed that vaccines were good for one's health and 73% had confidence on COVID-19 vaccine safety; although 81% of the respondents were particularly concerned about the source of the vaccine. 79% and 71% of respondents indicated their willingness for mandatory and voluntary COVID-19 vaccination, respectively. In all operationalized regression models, Ghanaians who believed that vaccines are healthy (OR = 1.998, Cl = 1.345-2.968; OR = 1.652, Cl = 1.050-2.601) and those who had confidence in a COVID-19 vaccine safety (OR = 4.405, Cl = 3.136-6.188; OR = 8.340, Cl = 5.471-12.713) were more likely to take a mandatory or voluntary COVID-19 vaccine compared to those who thought and believed otherwise. Individual preferences and/or intentions towards COVID-19 vaccine uptake and uptake route (i.e., mandatory, voluntary) were influenced by multifaceted determinants: biosocial (age, marital status, education), socio-cultural (religion, source of vaccine as a concern), and location (geographical zone) factors. Conclusion: To consolidate and possibly increase vaccine uptake in response to the COVID-19 pandemic in Ghana, health education and promotion programs should aim at creating awareness on the benefits of vaccine uptake while addressing the health and safety concerns on the potential side effects through evidence-based community messaging from credible sources. It is important to show specific commitment to transparency and reliable information to build public trust by decision-makers.

Mathematical analysis for the effect of voluntary vaccination on the propagation of Corona virus pandemic.

In this manuscript, a new nonlinear model for the rapidly spreading Corona virus disease (COVID-19) is developed. We incorporate an additional class of vaccinated humans which ascertains the impact of vaccination strategy for susceptible humans. A complete mathematical analysis of this model is conducted to predict the dynamics of Corona virus in the population. The analysis proves the effectiveness of vaccination strategy employed and helps public health services to control or to reduce the burden of corona virus pandemic. We first prove the existence and uniqueness and then boundedness and positivity of solutions. Threshold parameter for the vaccination model is computed analytically. Stability of the proposed model at fixed points is investigated analytically with the help of threshold parameter to examine epidemiological relevance of the pandemic. We apply LaSalle's invariance principle from the theory of Lyapunov function to prove the global stability of both the equilibria. Two well known numerical techniques namely Runge-Kutta method of order 4 (RK4), and the Non-Standard Finite Difference (NSFD) method are employed to solve the system of ODE's and to validate our obtained theoretical results. For different coverage levels of voluntary vaccination, we explored a complete quantitative analysis of the model. To draw our conclusions, the effect of proposed vaccination on threshold parameter is studied numerically. It is claimed that Corona virus disease could be eradicated faster if a human community selfishly adopts mandatory vaccination measures at various coverage levels with proper awareness. Finally, we have executed the joint variability of all classes to understand the effect of vaccination strategy on a disease dynamics.

Analysis of epidemic vaccination strategies on heterogeneous networks: Based on SEIRV model and evolutionary game.

Nowadays, vaccination is the most effective way to control the epidemic spreading. In this paper, an epidemic SEIRV (susceptible-exposed-infected-removed -vaccinated) model and an evolutionary game model are established to analyze the difference between mandatory vaccination method and voluntary vaccination method on heterogeneous networks. Firstly, we divide the population into four categories, including susceptible individuals, exposed individuals, infected individuals and removed individuals. Based on the mean field approximation theory, differential equations are developed to characterize the changes of the proportions of the four groups over time under mandatory vaccination. Then through the analysis of the differential equations, the disease-free equilibrium point (DFE) and the endemic disease equilibrium point (EDE) are obtained. Also, the basic reproduction number is obtained by the next-generation matrix method and the stability analysis of the equilibrium points is performed. Next, by considering factors such as vaccination cost, treatment cost and government subsidy rate, differential equations are established to represent the change of vaccination rate over time. By analyzing the final vaccination coverage rate, we can get the minimum vaccination cost to make infectious disease disappear. Finally, the Monte Carlo method is used for numerical simulation to verify the results obtained from the theoretical analysis. Using the SARS-Cov-2 pandemic data from Wuhan, China, the experimental results show that when the effectiveness rate of vaccination is 0.75, the vaccination cost is not higher than 0.886 so that the vaccination strategy can be spread among the population. If mandatory vaccination is adopted, the minimum vaccination rate is 0.146.

Trends in voluntary vaccination coverage in a Japanese city.

BACKGROUND: Large numbers of patients with diseases preventable by voluntary vaccines have been reported in Japan. However, it is difficult to analyze the impact of voluntary vaccination on disease prevention, as governments do not aggregate the number of recipients of vaccines that are not included in the national immunization program. This study investigated the association between the coverage rates of two voluntary vaccines (rotavirus and mumps vaccines) and the incidence of the diseases preventable by these vaccines. METHODS: We performed a prospective questionnaire-based observational study to investigate the presumptive coverage rates of the rotavirus vaccine in infancy and the mumps vaccine at 1 year of age in Kitakyushu City from 2015 to 2018. The number of children admitted to a secondary medical institution for rotavirus-associated gastroenteritis and the incidence of mumps infection in sentinel medical institutions were also analyzed during the investigation period. RESULTS: The rotavirus and mumps vaccine coverage rates since 2016 were 61-63% and late 28-30%, respectively (52.6% and 20.3% in 2015, respectively). The yearly number of children hospitalized for rotavirus-associated gastroenteritis from 2015 to 2018 declined by 41.4% compared with that during the pre-vaccination period (2009-2011). The incidence of mumps infection remained unchanged during the investigation period. CONCLUSION: The coverage rates of two voluntary vaccines were not high enough to control the infections. The incorporation of voluntary vaccines into the routine immunization program should be considered as the one of the effective ways to increase vaccination coverage.

Maternal influenza vaccination relates to receiving relevant information among pregnant women in Japan.

Maternal vaccination for seasonal influenza is currently not listed as a routine vaccination in the national vaccination schedule of Japan. However, many pregnant women voluntarily receive an influenza vaccination. We explored the factors related to influenza vaccine uptake. We particularly focused on factors related to any recommendation, such as advice or suggestions from another individual. We conducted a cross-sectional web-based questionnaire survey in Japan among pregnant women or mothers who had recently given birth in March 2017 and 2018. Logistic regression models were used to determine the factors influencing vaccination uptake. Key individuals regarding maternal vaccination were examined using the network visualization software Gephi. The total number of valid responses was 2204 in 2017 and 3580 in 2018. Over 40% of respondents had been vaccinated with the seasonal influenza vaccine at some point in both years. Of the vaccinated respondents, over 80% received advice regarding the influenza vaccination. Obstetricians were the most common source of advice in both years. Among respondents who chose more than two sources, the largest link in the network of sources was found between the obstetrician and family members. Attention to public concern or potential recommenders, by public health authorities, not just pregnant women, about the benefits of maternal influenza vaccination is important.

From mandatory to voluntary vaccination: intention to vaccinate in the case of policy changes.

OBJECTIVES: The aim of the study was to assess the association between sociodemographic characteristics and attitudes according to health belief model (HBM) attributes with the intention to vaccinate children in cases of non-mandatory vaccination to support informed decisions in planned revision of our vaccination policy. STUDY DESIGN: This is a cross-sectional study carried out on a random sample of 3,854 women with young children in Slovenia. METHODS: The participants' attitudes were grouped within six HBM attributes (perceived susceptibility, severity, benefits, barriers, clue to action and self-efficacy). Possible associations between the intention to vaccinate children in cases of non-mandatory vaccination and sociodemographic characteristics or attitudinal attributes according to HBM were explored in univariate analyses by calculating odds ratios (ORs) with 95% confidence interval (CI) estimates. RESULTS: Just more than half (56.2%; 95% CI: 53.8-58.5%) of the women reported on their intention to vaccinate their children in the case of non-mandatory vaccination, and 23.4% (95% CI: 21.4-25.5%) were undecided. There were no significant sociodemographic predictor variables in relation to this intention. Those who perceived higher susceptibility to vaccine-preventable diseases or the benefits of vaccination were more likely to intend to vaccinate in the case of non-mandatory vaccination (OR = 5.70; 95% CI: 4.64-7.00) and (OR = 7.62; 95% CI: 5.96-9.76). Perceived barriers to vaccinate (fear of side-effects or lack of comprehensive information from physicians) and parents not getting enough useful information in general as a clue to action were significant predictors of an intention not to vaccinate. CONCLUSIONS: Our results show that a mandatory vaccination policy is an important factor in ensuring high levels of vaccination coverage in Slovenia. In future, more comprehensive communication activities focused on vaccine-preventable diseases and the benefits and safety of vaccination (for the education of parents and their healthcare providers) are needed to diminish the reliance on a mandatory vaccination policy.

Using farmers' attitude and social pressures to design voluntary Bluetongue vaccination strategies.

Understanding the context and drivers of farmers' decision-making is critical to designing successful voluntary disease control interventions. This study uses a questionnaire based on the Reasoned Action Approach framework to assess the determinants of farmers' intention to participate in a hypothetical reactive vaccination scheme against Bluetongue. Results suggest that farmers' attitude and social pressures best explained intention. A mix of policy instruments can be used in a complementary way to motivate voluntary vaccination based on the finding that participation is influenced by both internal and external motivation. Next to informational and incentive-based instruments, social pressures, which stem from different type of perceived norms, can spur farmers' vaccination behaviour and serve as catalysts in voluntary vaccination schemes.

Factors that affect voluntary vaccination of children in Japan.

Some important vaccinations are not included in the routine childhood immunization schedule in Japan. Voluntary vaccinations are usually paid as an out-of-pocket expense. Low voluntary vaccination coverage rates and high target disease incidence are assumed to be a consequence of voluntary vaccination. Therefore, this study aimed to explore factors associated with voluntary vaccination patterns in children. We conducted an online survey of 1243 mothers from a registered survey panel who had at least one child 2 months to <3 years of age. The voluntary vaccination mainly correlated positively with annual household income and mothers' positive opinions about voluntary vaccinations, but negatively with number of children. Financial support, especially for low income households and households with more than one child, may motivate parents to vaccinate their children. Communication is also an important issue. More opportunities for education and information about voluntary vaccinations should be provided to mothers without distinguishing between voluntary and routine vaccination.

The current situation of voluntary vaccination and the factors influencing its coverage among children in Takatsuki, Japan: focus on Hib and pneumococcal vaccines.

This study aimed to understand the current scenario of voluntary vaccination and the factors influencing its coverage among 18-month-old children of Takatsuki City, Japan. Based on 1167 parents responses, we found that voluntary vaccination coverage rates were low when compared with routine vaccination rates. The children who were not the first born of the family and who had young and poorly educated parents were less likely to receive voluntary vaccination. Japanese government-supported vaccines, such as Haemophilus influenzae type b and pneumococcal vaccine, had a higher coverage than the vaccines for which parents had to bear the entire vaccination cost. Furthermore, it was found that mass communication media and family pediatricians were effective means to disseminate voluntary vaccination-related information. We envisage that an active participation of medical professionals, easy access to vaccinations, and mass awareness programs will increase voluntary vaccination coverage in Takatsuki.

Expected utility of voluntary vaccination in the middle of an emergent Bluetongue virus serotype 8 epidemic: a decision analysis parameterized for Dutch circumstances.

In order to put a halt to the Bluetongue virus serotype 8 (BTV-8) epidemic in 2008, the European Commission promoted vaccination at a transnational level as a new measure to combat BTV-8. Most European member states opted for a mandatory vaccination campaign, whereas the Netherlands, amongst others, opted for a voluntary campaign. For the latter to be effective, the farmer's willingness to vaccinate should be high enough to reach satisfactory vaccination coverage to stop the spread of the disease. This study looked at a farmer's expected utility of vaccination, which is expected to have a positive impact on the willingness to vaccinate. Decision analysis was used to structure the vaccination decision problem into decisions, events and payoffs, and to define the relationships among these elements. Two scenarios were formulated to distinguish farmers' mindsets, based on differences in dairy heifer management. For each of the scenarios, a decision tree was run for two years to study vaccination behaviour over time. The analysis was done based on the expected utility criterion. This allows to account for the effect of a farmer's risk preference on the vaccination decision. Probabilities were estimated by experts, payoffs were based on an earlier published study. According to the results of the simulation, the farmer decided initially to vaccinate against BTV-8 as the net expected utility of vaccination was positive. Re-vaccination was uncertain due to less expected costs of a continued outbreak. A risk averse farmer in this respect is more likely to re-vaccinate. When heifers were retained for export on the farm, the net expected utility of vaccination was found to be generally larger and thus was re-vaccination more likely to happen. For future animal health programmes that rely on a voluntary approach, results show that the provision of financial incentives can be adjusted to the farmers' willingness to vaccinate over time. Important in this respect are the decision moment and the characteristics of the disease. Farmers' perceptions of the disease risk and about the efficacy of available control options cannot be neglected.

Primary care physician practices, recommendations, and barriers to the provision of routine and voluntary vaccinations in Japan / 日本プライマリ・ケア連合学会誌

<b>Introduction</b> : Recommendations from healthcare providers are considered by vaccinees and their parents when they decide whether to receive an immunization. However, in Japan, the attitudes of primary care physicians toward vaccination are unknown. We assessed some practices and recommendations of, and barriers to, primary care physicians regarding vaccinations in Japan.<br><b>Methods</b> : A self-administered questionnaire was mailed (in 2012) to 3000 randomly selected physician-members of the Japan Primary Care Association. Excluded were physicians within two years after graduation, living abroad or retired. We described respondent practices, recommendations, and barriers to the provision of routine and voluntary vaccinations.<br><b>Results</b> : The overall response rate was 25.8%. The rates at which physicians gave routine and voluntary vaccines in their own practices were 29.0-91.4% and 15.2-89.5%, respectively. The vaccine recommendation rates for routine and voluntary vaccines were 58.2-70.2% and 14.1-50.9%, respectively. The physicians reported that their barriers to recommendation of routine vaccines were vaccination schedule complexity (32.9%), opinions of vaccinees and parents (28.9%), and vaccine safety (27.7%). They also reported that perceived vaccine safety (62.1%), lack of understanding of vaccine-preventable diseases (55.7%), and complexity of vaccine schedules (44.4%) were reasons given by vaccinees and parents for noncompliance. Physicians' barriers to recommendation of voluntary vaccines were cost (45.3%), safety (35.1%), and lack of information (30.1%). They reported that vaccinees and parents expressed concern about cost (61.8%), safety (51.8%), and lack of vaccine information (50.7%).<br><b>Conclusion</b> : We clarified practices, recommendations, and barriers to primary care physicians regarding routine and voluntary vaccination in Japan.

Risk estimation of infectious diseases determines the effectiveness of the control strategy.

Usually, whether to take vaccination or not is a voluntary decision, which is determined by many factors, from societal factors (such as religious belief and human rights) to individual preferences (including psychology and altruism). Facing the outbreaks of infectious diseases, different people often have different estimations on the risk of infectious diseases. So, some persons are willing to vaccinate, but other persons are willing to take risks. In this paper, we establish two different risk assessment systems using the technique of dynamic programming, and then compare the effects of the two different systems on the prevention of diseases on complex networks. One is that the perceived probability of being infected for each individual is the same (uniform case). The other is that the perceived probability of being infected is positively correlated to individual degrees (preferential case). We show that these two risk assessment systems can yield completely different results, such as, the effectiveness of controlling diseases, the time evolution of the number of infections, and so on.

The Policy of Full Subsidy for Six Voluntary Vaccinations and Community Education in Horokanai Town ; Effects on Vaccine Coverage / 日本プライマリ・ケア連合学会誌

 In Horokanai town, Hokkaido, the policy of full subsidies for voluntary vaccinations against influenza, haemophilus influenzae type b (Hib), varicella, mumps, pneumococcal for children and human papillomavirus (HPV) was introduced between 2008 and 2010. A campaign for community education about vaccination was initiated.<br> Vaccination coverage improved after the subsidy as follows : influenza vaccination increased from 57.4% to 60.1%, Hib from 2.9% to 52.2%, varicella from 0% to 30.0%, mumps from 2.8% to 38.2%, pneumococcal for children from 1.3% to 50.6%, and HPV from 0% to 81.3%.