Association Between Vaccine Refusal and Vaccine-Preventable Diseases in the United States: A Review of Measles and Pertussis

Infection Prevention and Control Implications of Special Pathogens in Children

Special pathogens are broadly defined as highly transmissible organisms capable of causing severe disease in humans. Children's hospital healthcare personnel (HCP) should be prepared to identify patients possibly infected with a special pathogen, isolate the patient to minimize transmission, and inform key infection prevention, clinical, and public health stakeholders. Effective preparedness requires resources and practice with attention to education, policies and procedures, drills and training, and supplies. Successfully preparing for special pathogens is an important measure toward keeping communities, HCP, and patients and families safe in this global age that brings pathogens from across the world to our doorstep.

Raising Epidemiological Awareness: Assessment of Measles/MMR Susceptibility in Highly Vaccinated Clusters within the Hungarian and Croatian Population-A Sero-Surveillance Analysis

Perceptions of the complete eradication of vaccine-preventable diseases such as measles, mumps, and rubella (MMR) may foster complacency and compromise vaccination efforts. Decreased measles vaccination rates during the COVID-19 pandemic have heightened the risk of outbreaks, even in adequately vaccinated populations. To address this, we have aligned with ECDC recommendations, leveraging previous cross-border sero-epidemiological assessments between Pécs, Hungary, and Osijek, Croatia, to identify latent risk groups and uncover potential parallels between our nations. Testing 2680 Hungarian and 1764 Croatian serum samples for anti-MMR IgG via ELISAs revealed anti-measles seropositivity ratios below expectations in Croatian cohorts aged ~20-30 (75.7%), ~30-40 (77.5%) and ~40-50 years (73.3%). Similarly, Hungarian samples also showed suboptimal seropositivity ratios in the ~30-40 (80.9%) and ~40-50 (87.3%) age groups. Considering mumps- and rubella-associated seropositivity trends, in both examined populations, individuals aged ~30-50 years exhibited the highest vulnerability. Additionally, we noted congruent seropositivity trends across both countries, despite distinct immunization and epidemiological contexts. Therefore, we propose expanding research to encompass the intricate dynamics of vaccination, including waning long-term immunity. This understanding could facilitate targeted interventions and bolster public awareness. Our findings underscore persistent challenges in attaining robust immunity against measles despite vaccination endeavors.

Attitudes towards COVID-19 vaccination: A cross sectional study in the Federal Capital Territory, Nigeria

Vaccine acceptance is complex and context-specific, varying across time, place and perceived behavioural nature of the community involved. A high vaccine acceptance rate is important to achieve herd immunity, however, vaccine hesitancy is a possible barrier to this. This study aimed to assess attitudes towards COVID-19 vaccination and associated factors. A cross-sectional survey was undertaken to investigate the attitudes of Federal Capital Territory residents towards COVID-19 vaccine uptake in Nigeria. Data were collected using questionnaires which were administered to respondents physically and online through random and snowball sampling strategies respectively. Data received were then analysed using Statistical Package for Social Sciences (SPSS). A total of 1767 responses were received with males representing 57.8% of the sample. More than half (54.9%) of the respondents were between the ages of 18-30 years. A third (35.4%) of the study participants indicated that a vaccine was not necessary for COVID-19, and 56.5% indicated willingness to accept COVID-19 vaccination. The majority of the sample (56.9%) indicated that the government decision-making was in their best interest, whilst close to two-thirds of the respondents (61%) were of the view that COVID-19 vaccination should not be made compulsory. Older respondents as represented by those over 60 years were more likely to accept COVID-19 vaccination (p = 0.039). This study however revealed negative attitudes towards COVID-19 vaccination, indicating the urgent need for government, policymakers, and other stakeholders to prioritise the development of strategies that can appropriately address vaccine hesitancy in the study setting. Contextual interventions indicated include strategic public enlightenment campaigns targeting populations with less favourable dispositions towards being vaccinated.

Vaccination Timeliness Among US Children Aged 0-19 Months, National Immunization Survey-Child 2011-2021

Importance

Delays in receiving vaccinations lead to greater vaccine-preventable disease risk. Timeliness of receipt of recommended vaccinations is not routinely tracked in the US, either overall or for populations that have known barriers to accessing routine health care, including lower-income families and children.

Objective

To measure vaccination timeliness among US children aged 0 to 19 months, overall and by socioeconomic indicators.

Design, Setting, and Participants

This serial, cross-sectional study analyzed nationally representative data from the 2011 to 2021 National Immunization Survey-Child (NIS-Child), an annual survey of parents, with immunization histories collected from clinicians administering vaccines. The 2020 and 2021 surveys largely reflected vaccinations in the US before the COVID-19 pandemic. Study participants included US children surveyed at ages 19 to 35 months. Data were analyzed from January to August 2023.

Exposure

Survey year.

Main Outcomes and Measures

The primary outcomes were average days undervaccinated (ADU) and percentage of children who received all vaccine doses on time (ie, 0 days undervaccinated) for the combined 7-vaccine series up to age 19 months. The mean adjusted annual change in on-time vaccination by socioeconomic indicators was calculated by use of multivariable log-linked binomial regression models.

Results

The surveys included 179 154 children (92 248 boys [51.2%]); 74 479 (31.4%, weighted) lived above the federal poverty level with more than $75 000 in annual family income, 58 961 (32.4%) lived at or above the poverty level with $75 000 or less in annual family income, and 39 564 (30.2%) lived below the poverty level. Overall, the median (IQR) ADU for the combined 7-vaccine series in the US decreased from 22.3 (0.4-71.5) days in the 2011 survey to 11.9 (0.0-55.5) days in the 2021 survey. The prevalence of on-time receipt of the combined 7-vaccine series increased from 22.5% (95% CI, 21.4%-23.6%) to 35.6% (95% CI, 34.2%-37.0%). Although children with more than $75 000 in annual family income had a 4.6% (95% CI, 4.0%-5.2%) mean annual increase in on-time vaccination, the mean annual increase was 2.8% (95% CI, 2.0%-3.6%) for children living at or above the poverty level with $75 000 or less in annual family income and 2.0% (95% CI, 1.0%-3.0%) for children living below the poverty level.

Conclusions and Relevance

In this cross-sectional study of NIS-Child data, improvements in vaccination timeliness were observed from the 2011 to the 2021 survey. However, widening disparities by socioeconomic indicators signal that increased efforts to facilitate timely vaccination among children in lower-income families are needed.

Impact of BCG Vaccination Disruptions During the COVID-19 Pandemic on Tuberculosis Incidence in Infants: A Nationwide Study in Brazil

Pandemic-related disruptions led to lower Bacille Calmette-Guérin (BCG) vaccine coverage in Brazil. This study highlights a link between reduced vaccinations and increased tuberculosis pulmonary and extrapulmonary cases in infants. Addressing vaccine hesitancy and ensuring healthcare stability is vital for mitigating impacts.

Modification and Validation of the Vaccine Hesitancy Scale for Turkish Adult Vaccination

Background and Purpose: For public health, it is important to investigate vaccine hesitancy, determine populations reluctant for vaccines, and investigate barriers and facilitators for vaccination in these groups. This study aims to modify and validate the Vaccine Hesitancy Scale specific to adults in Turkish society. Methods: The study, which was designed as a methodological and survey type, was conducted using a Google questionnaire with 720 participants who met the inclusion criteria with a convenient sampling method. Results: After factor and reliability analysis, a 2-factor, 10-item scale with an acceptable and perfect range of fit index values emerged. It has been observed that individuals who are young, single, do not have children, have vaccine allergy, and do not believe that the vaccine will protect the society are adversely affected by the environment, and those who do not have COVID-19 and flu have a high level of hesitancy to vaccine. Conclusions: The Vaccine Hesitancy Scale is a valid and reliable tool to detect vaccine hesitation in adults in Turkish society.

Overview of childhood vaccination coverage in Brazil and the impact of the COVID-19 pandemic: Is our children's health at risk? A review of pre-COVID-19 periods and during the COVID-19 pandemic

Introduction

The coronavirus disease (COVID)-19 has had a great impact on several aspects related to the population's health, including the vaccination adherence rate. This study describes how childhood vaccination coverage (CVC) in Brazil was affected by the pandemic in the period from 2020 to 2022 and explores the relationship between this data and the Human Development Index (HDI), and the number of votes received in the government with a right-wing political ideology.

Methods

An ecological analysis of CVC was carried out including 12 vaccines. The HDI was evaluated considering the HDI-General, HDI-Income, HDI-Longevity, and HDI-Education. The percentage of valid votes received by the former president (right-wing political ideology) was also obtained. Spearman correlation tests were applied to compare markers.

Results

During the period analyzed, it was observed a linear growth trend in CVC between 2015 and 2018 regarding all vaccines. However, from 2018 onwards, after the presidential elections in Brazil, the CVC reduced significantly, showing an even more pronounced decrease with the start of the COVID-19 pandemic. This reduction in CVC observed for some vaccines was related to the higher percentage of votes for the government with a right-wing political ideology, especially in relation to the BCG (bacillus Calmette and Guerin) and pentavalent (protecting against diphtheria, tetanus, pertussis, hepatitis B, and Haemophilus influenzae type b bacteria) vaccines. In addition, when analyzing the HDI, it was observed that the lowest values of this indicator were associated with a more expressive reduction in CVC, mainly related to yellow fever, pentavalent, 10-valent pneumococcal conjugate, Human rotavirus, and triple viral (protecting against measles, mumps, and rubella - MMR) vaccines.

Conclusion

Although Brazil has a successful and exemplary record in combating several diseases, mainly due to the high rate of CVC, the continuous reduction in this coverage must be thoroughly evaluated by health managers.

Strategies for Improving Vaccine Communication and Uptake

Vaccines have led to a significant decrease in rates of vaccine-preventable diseases and have made a significant impact on the health of children. However, some parents express concerns about vaccine safety and the necessity of vaccines. The concerns of parents range from hesitancy about some immunizations to refusal of all vaccines. This clinical report provides information about the scope and impact of the problem, the facts surrounding common vaccination concerns, and the latest evidence regarding effective communication techniques for the vaccine conversation. After reading this clinical report, readers can expect to: Understand concepts and underlying determinants of vaccine uptake and vaccine hesitancy.Understand the relationship between vaccine hesitancy and costs of preventable medical care.Recognize and address specific concerns (eg, vaccine safety) with caregivers when hesitancy is present.

Digital Gamification Tools to Enhance Vaccine Uptake: Scoping Review

BACKGROUND

Gamification has been used successfully to promote various desired health behaviors. Previous studies have used gamification to achieve desired health behaviors or facilitate their learning about health.

OBJECTIVE

In this scoping review, we aimed to describe digital gamified tools that have been implemented or evaluated across various populations to encourage vaccination, as well as any reported effects of identified tools.

METHODS

We searched Medline, Embase, CINAHL, the Web of Science Core Collection, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, Academic Search Premier, PsycInfo, Global Health, and ERIC for peer-reviewed papers describing digital gamified tools with or without evaluations. We also conducted web searches with Google to identify digital gamified tools lacking associated publications. We consulted 12 experts in the field of gamification and health behavior to identify any papers or tools we might have missed. We extracted data about the target population of the tools, the interventions themselves (eg, type of digital gamified tool platform, type of disease/vaccine, type and design of study), and any effects of evaluated tools, and we synthesized data narratively.

RESULTS

Of 1402 records, we included 28 (2%) peer-reviewed papers and 10 digital gamified tools lacking associated publications. The experts added 1 digital gamified tool that met the inclusion criteria. Our final data set therefore included 28 peer-reviewed papers and 11 digital gamified tools. Of the 28 peer-reviewed papers, 7 (25%) explained the development of the tool, 16 (57%) described evaluation, and 2 (7%) reported both development and evaluation of the tool. The 28 peer-reviewed papers reported on 25 different tools. Of these 25 digital gamified tools, 11 (44%) were web-based tools, 8 (32%) mobile (native mobile or mobile-enabled web) apps, and 6 (24%) virtual reality tools. Overall, tools that were evaluated showed increases in knowledge and intentions to receive vaccines, mixed effects on attitudes, and positive effects on beliefs. We did not observe discernible advantages of one type of digital gamified tool (web based, mobile, virtual reality) over the others. However, a few studies were randomized controlled trials, and publication bias may have led to such positive effects having a higher likelihood of appearing in the peer-reviewed literature.

CONCLUSIONS

Digital gamified tools appear to have potential for improving vaccine uptake by fostering positive beliefs and increasing vaccine-related knowledge and intentions. Encouraging comparative studies of different features or different types of digital gamified tools could advance the field by identifying features or types of tools that yield more positive effects across populations and contexts. Further work in this area should seek to inform the implementation of gamification for vaccine acceptance and promote effective health communication, thus yielding meaningful health and social impacts.

A population level study on the determinants of COVID-19 vaccination rates at the U.S. county level

Multiple COVID-19 vaccines were proven to be safe and effective in curbing severe illness, but despite vaccine availability, vaccination rates were relatively low in the United States (U.S.). To better understand factors associated with low COVID-19 vaccine uptake in the U.S., our study provides a comprehensive, data-driven population-level statistical analysis at the county level. We find that political affiliation, as determined by the proportion of votes received by the Republican candidate in the 2020 presidential election, has the strongest association with our response variable, the percent of the population that received no COVID-19 vaccine. The next strongest association was median household income, which has a negative association. The percentage of Black people and the average number of vehicles per household are positively associated with the percent unvaccinated. In contrast, COVID-19 infection rate, percentage of Latinx people, postsecondary education percentage, median age, and prior non-COVID-19 childhood vaccination coverage are negatively associated with percent unvaccinated. Unlike previous studies, we do not find significant relationships between cable TV news viewership or Twitter misinformation variables with COVID-19 vaccine uptake. These results shed light on some factors that may impact vaccination choice in the U.S. and can be used to target specific populations for educational outreach and vaccine campaign strategies in efforts to increase vaccination uptake.

Vaccine decision making in New Zealand: a discrete choice experiment

BACKGROUND

Vaccine hesitancy is a significant threat to global health. A key part of addressing hesitancy is to ensure that public health messaging prioritises information that is considered important to the public. This study aimed to examine how different vaccine characteristics affect public preferences for vaccines in New Zealand, what trade-offs they are willing to make between different vaccine characteristics, and how their preferences are affected by their vaccine-related conspiracy beliefs and COVID-19 vaccination status.

METHODS

An online discrete choice experiment (DCE) was designed to elicit individual preferences about vaccines using the 1000minds platform. Members of the general population of New Zealand aged ≥ 18 years were invited to complete the DCE. Participants were asked to indicate their preference between two options showing different combinations of vaccine characteristics. Data on sociodemographic characteristics were collected. Beliefs were measured using the vaccine conspiracy beliefs scale (VCBS) with scores ≥ 19 indicating strong vaccine-related conspiracy beliefs. The DCE was analysed using the PAPRIKA method (Potentially All Pairwise RanKings of all possible Alternatives) and preferences compared between respondents with high versus low VCBS scores and vaccinated versus unvaccinated respondents for COVID-19.

RESULTS

A total of 611 respondents from 15 regions completed the DCE. Mean (SD) age was 45.9 (14.7) years with most having had 2 or more doses of the coronavirus vaccine (86%). Mean (SD) VCBS score was 18.5 (12.4) indicating moderate vaccine-related conspiracy beliefs. Risk of severe adverse effects was the most highly valued vaccine characteristic, followed by vaccine effectiveness and duration of protection. Vaccine origin and route of administration were ranked least important. Respondents scoring high on the VCBS placed less value on the effectiveness of vaccines but greater value on development time and total number of doses (p < 0.001). COVID-19 unvaccinated respondents ranked development time and total number of doses more highly than those vaccinated respondents (p < 0.001).

CONCLUSIONS

Risk of severe adverse effects, vaccine effectiveness and duration of protection were rated by the New Zealand public as the top three most important vaccine characteristics. This information is important for informing public health messaging to promote vaccine uptake and inform vaccine decision-making.

Effectiveness and safety of a mumps containing vaccine in preventing laboratory-confirmed mumps cases from 2002 to 2017: A meta-analysis

Emerging evidence has figured that serum conversion rate of mumps is a crucial link of mumps disease. Nevertheless, a rising number of mumps outbreaks caused our attention and studies examining the serum conversion cases were conducted in small samples previously; this meta-analysis was conducted to assess the immunogenicity and safety of a mumps containing vaccine (MuCV) before 2019. We identified a total of 17 studies from the year of 2002-2017. In the case-control studies, the vaccine effectiveness (VE) of MuCV in preventing laboratory-confirmed mumps was 68% (odds risk: 0.32; 95% confidence interval [CI], 0.14-0.70) while in the cohort studies and randomised control trials, 58% (relative risk [RR]: 0.42; 95% CI, 0.26-0.69). Similar intervals of effectiveness rates were found during non-outbreak periods compared with outbreak periods (VE: 66%; RR: 0.34; 95% CI, 0.18-0.68 versus VE: 49%; RR: 0.51; 95% CI, 0.21-1.27). In addition, the MuCV group with two and three doses did not show enhanced laboratory-confirmed mumps than one dose (VE: 58%; RR: 0.42; 95% CI, 0.20-0.88 versus VE: 65%, RR: 0.35; 95% CI, 0.20-0.61) for the reason of the overlap of 95% CI. MuCV had comparable effectiveness comparing non-outbreak and outbreak period, one dose, and two or three doses. MuCV displayed acceptable adverse event profiles.

Coverage and determinants of childhood vaccination during the COVID-19 pandemic in Fortaleza, Northeastern Brazil: a longitudinal analysis

Brazil has seen a decrease in vaccination coverage since 2016. This study analyzes the immunization status of children born during the COVID-19 pandemic in Fortaleza, Northeastern Brazil. This is a longitudinal analysis that included vaccination data of 313 children aged 12 and 18 months. Vaccination cards were checked for dose application considering the schedule of immunization recommended by the Brazilian Ministry of Health. Factors associated with no retention of vaccination cards and incomplete immunization by 18 months were identified by Tobit regression analysis. About 73% of mothers presented their child's vaccination card. Non-availability of vaccination cards was associated with maternal age < 25 years and mothers with paid jobs. Only 33% and 45% of the children aged 12 and 18 months had all vaccines up to date, respectively. For 3-dose vaccines, the delay rate was around 10% for the first dose application, but 40% for the third dose. Despite delays, most children with available vaccine cards had coverage above 90% by 18 months of age. Adjusted factors associated with incomplete vaccination included living in a household with more than one child (p = 0.010) and monthly income of less than one minimum wage (p = 0.006). Therefore, delays in child vaccine application were high during the COVID-19 pandemic but a considerable uptake by 18 months of age was found. Poorer families with more than one child were particularly at risk of not fully immunizing their children and should be the target of public policies.

A survey of college students' knowledge and attitudes regarding vaccination practices

Objective: The prevalence of illnesses related to VPDs is higher among older adults and college students experience them despite decades of vaccine availability. The Centers for Disease Control and Prevention and American College Health Association (ACHA) emphasizes that all students should provide vaccine proof or receive immunizations prior to class registration. Methods: Using the KAP model, this study investigates the perceptions of first-generation university students regarding campus vaccine requirements. Data were collected using the Web-based survey software Qualtrics regarding students' vaccine knowledge and attitudes. Results: Of the 1,327 responses, the majority were female (74.23%), Hispanic (56.67%), and ages 18-25 years (35.57%). Participants were familiar with the function of vaccines (96.64%) and believed that vaccines prevent contagious diseases (92.70%). These responses were significantly associated with vaccination compliance however, 18.48% of students were not in full compliance. There were significant differences in vaccination compliance across academic standing, age, and race. Conclusion: Implications for public health practices on university campuses are discussed.

Non-vaccination of dogs is linked to uncompleted COVID-19 vaccination protocols of owners

Despite the known importance of vaccines as one of the greatest achievements in medical science, vaccine hesitancy has been increasing in the last decade and has become a major threat to global health. The growth of vaccine hesitancy worldwide became more evident with the onset of COVID-19 and raised the fear that this hesitancy would also impact companion animal vaccination. This study aimed to characterize vaccine-hesitant groups regarding companion animals and human vaccinations, as well as to explore the possible association between vaccine hesitancy in pets and their owners. An anonymous online survey containing 27 closed questions was conducted, including questions about dog health, such as vaccination, neutering, and homeopathy use, as well as questions about the COVID-19 vaccination status of the owner and motivations for vaccinating or not vaccinating their pets. Most participants (81.5 %) reported receiving three or more doses of the COVID-19 vaccine. Not vaccinating against COVID-19 or having an incomplete vaccination protocol was associated with an increase in the age range of participants (odds ratio [OR] = 1.43), not having higher education (OR = 7.70), and being in extreme income ranges (less than two minimum wages [OR = 7.57] and more than 10 [OR = 5.20]). The use of homeopathy in humans (OR = 3.24) and dogs (OR = 3.74) was associated with non-vaccination against COVID-19. Owners who were not fully vaccinated against COVID-19 were almost six times more likely to not vaccinate their dogs (OR = 5.94). Non-vaccination of dogs was also associated with non-neutering (OR = 3.56), keeping the dog in contact with other dogs (OR = 2.09), and an increase in the number of dogs in the house increased the chance of not vaccinating the animals (OR = 1.30). The present study revealed a strong association between non-vaccination against COVID-19 and non-vaccination in companion dogs, raising the hypothesis that vaccination hesitancy is a growing challenge in veterinary medicine. In addition, the characteristics of Brazilians who are reluctant to be vaccinated against COVID-19 or immunize their companion animals are described here for the first time.

Routine childhood immunization in Sub-Saharan Africa: addressing parental vaccine hesitancy

OBJECTIVES

Parental vaccine hesitancy (VH) is a major barrier to childhood vaccination. We aimed to identify the determinants of parental VH towards routine childhood immunization in 12 Sub-Saharan African countries.

STUDY DESIGN

A cross-sectional study was conducted from November 1 to December 15, 2022.

METHODS

Parents of children aged 19 months to 6 years and residing in the Sub-Saharan Africa were included. An anonymous online survey and face-to-face interviews were conducted. The Parent Attitude about Childhood Vaccine Scale was used to identify vaccine-hesitant parents. Multivariate regression and mediating analysis were performed.

RESULTS

Across the 5032 participants, 21.2% were hesitant towards routine childhood immunization. Urban residents (adjusted odds ratio [AOR] = 1.32, 95% confidence interval [CI]: 1.10-1.58), non-first-born children (AOR = 1.54, 95% CI: 1.19-1.98), and chronically ill children (AOR = 2.00, 95% CI: 1.69-2.37) increased the likelihood of parental VH. Mothers with higher education, attending at least one antenatal care (ANC) visit (AOR = 0.25, 95% CI: 0.19-0.32), and had a healthcare facility-based delivery (AOR = 0.55, 95% CI: 0.44-0.70) decreased the odds of parental VH. Parental VH mediated the effect of ANC and mothers' age on vaccination uptake. ANC increased the odds of vaccination uptake (odds ratio [OR] = 12.49, 95% CI: 9.68-16.13). Parental VH mediated the association between ANC and vaccination uptake, decreasing the likelihood of vaccination uptake (OR = 0.12, 95% CI: 0.10-0.14). Each additional year of the mother's age decreased the odds of vaccination uptake (OR = 0.95, 95% CI: 0.95-0.96). The indirect effect of mother's age on vaccination through parental VH decreased the odds of vaccination uptake (OR = 0.45, 95% CI: 0.44-0.45). Parental VH continued to be a mediator of the combined effect of mother's age and ANC on vaccination uptake, decreasing the likelihood of vaccination uptake (OR = 0.0017, 95% CI: 0.00166-0.00168).

CONCLUSIONS

Context-specific interventions are needed to address parental VH and improve vaccine acceptance and coverage.

Worldwide Child Routine Vaccination Hesitancy Rate among Parents of Children Aged 0-6 Years: A Systematic Review and Meta-Analysis of Cross-Sectional Studies

Routine vaccine hesitancy is a major global health challenge observed in over 190 countries worldwide. This meta-analysis aims to determine the worldwide prevalence of routine vaccination hesitancy among parents of children aged 0-6. An extensive search was conducted in four scientific databases: PubMed, Scopus, Web of Science, and the Cochrane Library. Studies were included if they reported hesitancy related to WHO-recommended routine immunizations for children under 7 years of age. A single-arm meta-analysis was performed using the OpenMeta[Analyst] software. An initial search retrieved 5121 articles, of which only 23 publications, involving 29,131 parents, guardians, and caregivers from over 30 countries met the inclusion criteria and quality assessment. The cumulative prevalence of parental vaccine hesitancy was found to be 21.1% (95% CI = 17.5-24.7%, I2 = 98.86%, p < 0.001). When stratifying the prevalence of vaccine hesitancy per WHO region, significant variations were observed, ranging from 13.3% (95% CI = 6.7-19.9%, I2 = 97.72%, p < 0.001) in the Region of the Americas to 27.9% (95% CI = 24.3-31.4%) in the Eastern Mediterranean region. The study findings highlight the need for healthcare providers and governments to develop and improve comprehensive programs with communication strategies to reduce parental vaccine hesitancy.

Hearing Loss after COVID-19 and Non-COVID-19 Vaccination: A Systematic Review

(1) Background: Vaccine safety is an important topic with public health implications on a global scale. The purpose of this study was to systematically review available literature assessing sensorineural hearing loss (SNHL) incidence and severity following both coronavirus disease 2019 (COVID-19) and non-COVID-19 vaccinations, as well as prognosis and outcomes. (2) Methods: This systematic review was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Relevant publications evaluating post-vaccination SNHL were selected from PubMed and Embase, searching from inception to July 2023. (3) Results: From 11 observational studies, the incidence of post-vaccination SNHL was low for both COVID-19 and non-COVID-19 vaccines, ranging from 0.6 to 60.77 per 100,000 person-years, comparable to all-cause SNHL. (4) Conclusions: The incidence rates of SNHL following COVID-19 and non-COVID-19 vaccinations remained reassuringly low. Most patients experienced improved hearing function in the weeks to months following vaccination. This study underscores the importance and safety of vaccinations and encourages ongoing surveillance and detailed reporting of hearing loss cases post-vaccination.

Vaccine Hesitancy in Central Switzerland: Identifying and Characterizing Undervaccinated Children in a Pediatric Emergency Department

Vaccinations play an important role in the prevention of potentially fatal diseases. Vaccine hesitancy has become an important problem both in the public discourse and for public health. We aimed to identify and characterize this potentially unvaccinated or incompletely vaccinated group of children presenting to the pediatric emergency department (PED) of the tertiary children's hospital in central Switzerland, a region that has anecdotally been claimed as a hotspot for vaccine hesitancy. All patients presenting to the PED (N = 20,247) between September 2018 and September 2019 were screened for their vaccination status and categorized as incomplete, unvaccinated, or fully vaccinated in a retrospective cohort study. Some 2.6% (n = 526) visits to the PED were not or incompletely vaccinated according to age, or their vaccination status was unknown. Most of the children in the cohort were not critically ill, and the minority had to be hospitalized. Undervaccinated patients were overrepresented in rural areas. Of all cohort visits, 18 (3.4%) patients received opportunistic vaccination in the PED. No cases of vaccine-preventable diseases were observed. In summary, incompletely vaccinated and unvaccinated status was less frequent than initially expected. The PED may play a role in increasing vaccination coverage by providing opportunistic vaccinations.

Modifiable risk factors for diphtheria: A systematic review and meta-analysis

Objective

To identify modifiable risk factors for diphtheria and assess their strengths of association with the disease.

Methods

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Electronic databases and grey literature were searched from inception until January 2023. Studies had to report on diphtheria cases and estimates of association for at least one potential risk factor or sufficient data to calculate these. The quality of non-ecological studies was assessed using the Newcastle-Ottawa Scale (NOS), while the quality of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

Results

The search yielded 37,705 papers, of which 29 were ultimately included. All the non-ecological studies were of moderate to high quality. Meta-analysis of 20 studies identified three factors increasing the risk of diphtheria: incomplete vaccination (<3 doses) (pooled odds ratio (POR) = 2.2, 95% confidence interval (CI) = 1.4-3.4); contact with a person with skin lesions (POR = 4.8, 95% CI = 2.1-10.9); and low knowledge of diphtheria (POR = 2.4, 95% CI = 1.2-4.7). Contact with a case of diphtheria; sharing a bed or bedroom; sharing utensils, cups, and glasses; infrequent bathing; and low parental education were associated with diphtheria in multiple studies. Evidence for other factors was inconclusive. The quality of evidence was low or very low for all the risk factors.

Conclusions

Findings from the review suggest that countries seeking to control diphtheria need to strengthen surveillance, improve vaccination coverage, and increase people's knowledge of the disease. Future research should focus on understudied or inconclusive risk factors.

Ethics and non-evidence based therapies: Portuguese perspective in a global setting

A contemporary serious lack of scientific knowledge by the general public and many decision-makers is now quite perceptible, both globally and in Portugal. Living in a science-driven technological world filled with scientific illiteracy is dangerous and a path toward disaster. Recent years brought a fairly strong global movement promoting the so-called "alternative therapy" that also affected Portugal. I propose an evidence-based ethics reflection and argumentation, both encompassing the global and the specific Portuguese reality. I debate the specific arguments used in favour of alternative therapies, demonstrating the inherent fallacies of thought, deliberate manipulation of words and concepts, and the dire consequences for global and local health politics by following this line of biased reasoning.

"Messengers matter": Assessing the impact of racially concordant care on vaccine hesitation

With the rise in COVID-related deaths among the unvaccinated, understanding coronavirus vaccine hesitancy is critical to maintaining public health. Previous research has shown that sociodemographic factors, such as race, are essential for understanding vaccine hesitancy; yet, the specific factors driving racial disparities in vaccination continue to be a matter of intense debate. This study uses a novel survey experiment to uncover the linkages between race, physician trust, and vaccine hesitancy. Using a standard prompt on the release of the COVID-19 vaccine, it tests whether patient-physician race concordance affects the likelihood of vaccine uptake among US citizens. Analyses reveal that racially concordant care has a negligible effect on vaccine hesitancy, but does ameliorate other harmful beliefs regarding one's likelihood of experiencing discrimination and racism in healthcare more generally. These findings suggest that increasing diversity in the medical field should be paired with efforts to address systemic inequalities to promote increased vaccination.

Determinants of parental vaccine hesitancy in Canada: results from the 2017 Childhood National Immunization Coverage Survey

BACKGROUND

In 2019, the World Health Organization (WHO) designated vaccine hesitancy as one of the ten leading threats to global health. Vaccine hesitancy exists when vaccination services are available and accessible, but vaccine uptake is lower than anticipated. It is often attributed to lack of trust in vaccine safety and effectiveness, or low level of concern about the risk of many vaccine-preventable diseases. This study aimed to examine the sociodemographic factors associated with parental vaccine hesitancy and vaccine refusal in Canada using data from the 2017 Childhood National Immunization Coverage Survey (CNICS).

METHOD

The 2017 CNICS was a cross-sectional and nationally representative survey to estimate national vaccine uptake and to collect information about parents' Knowledge, Attitudes and Beliefs (KAB) regarding vaccination. Using the KAB questions, parental vaccine hesitancy (i.e., parental hesitation, delay or refusal of at least one recommended vaccination) and refusal (i.e., unvaccinated children) by sociodemographic factors was estimated using weighted prevalence proportions. A multinomial logistic regression model was fitted to examine associations between parental vaccine hesitancy or refusal and sociodemographic factors among parents of two-year-old children in Canada. Adjusted odds ratios (aOR) of being vaccine-hesitant or vaccine-refusing versus being non-vaccine-hesitant were generated.

RESULTS

Both unadjusted and adjusted logistic regressions models showed that parents with lower household income (aOR 1.7, 95% CI 1.2-2.5), and those with a higher number of children in the household (aOR 2.2, 95% CI 1.4-3.5) had higher vaccine hesitancy. Conversely, lower vaccine hesitancy was observed among non-immigrant parents (aOR 0.4, 95% CI 0.3-0.6). In addition, lower household income (aOR 4.0, 95% CI 1.3-12.9), and higher number of children in the household (aOR 6.9, 95% CI 2.1-22.9) were significantly associated with parental vaccine refusal. Regional variations were also observed.

CONCLUSION

Several sociodemographic determinants are associated with parental vaccine hesitancy and refusal. The findings of the study could help public health officials and policymakers to develop and implement targeted interventions to improve childhood vaccination programs.

Development of a vaccine hesitancy scale for childhood immunization in China

OBJECTIVE

Vaccine hesitancy is a primary factor that influences vaccine uptake; however, no specific measurement tool to accurately assess vaccine hesitancy is available in China. This study aimed to develop a general vaccine hesitancy scale for childhood immunization.

METHODS

We adopted a three-phase process with nine steps to develop and finalize our scale. The scale framework and initial item pool were determined by a literature review. Expert consultation and cognitive interviews with parents were conducted to evaluate content validity. Questionnaire surveys involving parents of children aged <6 years were conducted to select items. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were employed to identify and validate the scale factor structure. The scale's reliability and validity were assessed using multiple indicators.

RESULTS

Of the initial 38 items, 21 were retained after expert consultation and cognitive interviews. In survey 1, the number of scale items decreased to 16 following item analysis and EFA. In survey 2, four items were added and EFA identified four factors. In survey 3, CFA confirmed the four-factor structure and the reliability indicators were satisfactory for the total scale. The level of vaccine hesitancy assessed by our scale was positively associated with vaccination refusal behavior and the Vaccine Hesitancy Scale score. The final scale comprised four dimensions (confidence, complacency, convenience, and calculation) with 17 items.

CONCLUSIONS

We developed a validated and reliable measurement to assess vaccine hesitancy among parents of children, which promises to be suitable for wide use in China.

Review: Factors influencing parents' decisions to vaccinate children against COVID-19

INTRODUCTION

Vaccination is a cornerstone of public health, significantly safeguarding children's health. Despite the imperative of achieving extensive COVID-19 vaccine coverage, vaccine hesitancy poses a major challenge.

OBJECTIVE

This review's aim is to analyze parental COVID-19 vaccine acceptance and hesitancy during the COVID-19 pandemic and elucidate the factors that influenced their decisions.

METHODS

A search of Medline (PubMed), Embase, and Psycinfo was conducted on February 1, 2022. The inclusion criteria were limited to observational studies that specifically evaluated parental COVID-19 vaccine acceptance or hesitancy for children, published in English. Studies that did not focus on this specific assessment, interventional studies, clinical trials, and secondary literature were excluded.

RESULTS

In reviewing 27 articles, parental vaccination acceptance rates were found to be different worldwide. Despite this, most of the articles found the same set of factors impacting parental COVID-19 vaccine acceptance and hesitancy. Parents' age, education, race, children's age, and annual household income were the main sociodemographic factors in vaccination decisions. Other common factors were the perceived risk and benefits of the COVID-19 vaccine, the source of information, parents' acceptance of receiving vaccinations themselves, and previous acceptance of the influenza vaccine. By reviewing parents' willingness to accept the COVID-19 vaccine for their children, it became clear that a lack of information about vaccine safety and efficacy was the most common factor affecting their decision.

CONCLUSION

This review identified critical factors affecting parents' vaccination behavior for their children. Awareness of these factors may reduce parents' COVID-19 vaccine refusal for their children and guide future planning and development of public health studies.

Internal and external factors affecting vaccination coverage: Modeling the interactions between vaccine hesitancy, accessibility, and mandates

Society, culture, and individual motivations affect human decisions regarding their health behaviors and preventative care, and health-related perceptions and behaviors can change at the population level as cultures evolve. An increase in vaccine hesitancy, an individual mindset informed within a cultural context, has resulted in a decrease in vaccination coverage and an increase in vaccine-preventable disease (VPD) outbreaks, particularly in developed countries where vaccination rates are generally high. Understanding local vaccination cultures, which evolve through an interaction between beliefs and behaviors and are influenced by the broader cultural landscape, is critical to fostering public health. Vaccine mandates and vaccine inaccessibility are two external factors that interact with individual beliefs to affect vaccine-related behaviors. To better understand the population dynamics of vaccine hesitancy, it is important to study how these external factors could shape a population's vaccination decisions and affect the broader health culture. Using a mathematical model of cultural evolution, we explore the effects of vaccine mandates, vaccine inaccessibility, and varying cultural selection trajectories on a population's level of vaccine hesitancy and vaccination behavior. We show that vaccine mandates can lead to a phenomenon in which high vaccine hesitancy co-occurs with high vaccination coverage, and that high vaccine confidence can be maintained even in areas where access to vaccines is limited.

Can delay discounting predict vaccine hesitancy 4-years later? A study among US young adults

Despite being a major threat to health, vaccine hesitancy (i.e., refusal or reluctance to vaccinate despite vaccine availability) is on the rise. Using a longitudinal cohort of young adults (N = 1260) from Los Angeles County, California we investigated the neurobehavioral mechanisms underlying COVID-19 vaccine hesitancy. Data were collected at two time points: during adolescence (12th grade; fall 2016; average age = 16.96 (±0.42)) and during young adulthood (spring 2021; average age = 21.33 (±0.49)). Main outcomes and measures were delay discounting (DD; fall 2016) and tendency to act rashly when experiencing positive and negative emotions (UPPS-P; fall 2016); self-reported vaccine hesitancy and vaccine beliefs/knowledge (spring 2021). A principal components analysis determined four COVID-19 vaccine beliefs/knowledge themes: Collective Responsibility, Confidence and Risk Calculation, Complacency, and Convenience. Significant relationships were found between themes, COVID-19 vaccine hesitancy, and DD. Collective Responsibility (β = -1.158[-1.213,-1.102]) and Convenience (β = -0.132[-0.185,-0.078]) scores were negatively associated, while Confidence and Risk Calculation (β = 0.283[0.230,0.337]) and Complacency (β = 0.412[0.358,0.466]) scores were positively associated with COVID-19 vaccine hesitancy. Additionally, Collective Responsibility (β = -0.060[-0.101,-0.018]) was negatively associated, and Complacency (β = -0.063[0.021,0.105]) was positively associated with DD from fall 2016. Mediation analysis revealed immediacy bias during adolescence, measured by DD, predicted vaccine hesitancy 4 years later while being mediated by two types of vaccine beliefs/knowledge: Collective Responsibility (β = 0.069[0.022,0.116]) and Complacency (β = 0.026[0.008,0.044]). These findings provide a further understanding of individual vaccine-related decision-making among young adults and inform public health messaging to increase vaccination acceptance.

Psychological and Social Aspects of Vaccination Hesitancy-Implications for Travel Medicine in the Aftermath of the COVID-19 Crisis: A Narrative Review

Vaccines are an important tool of preventive medicine. Although organized vaccination programs have saved large populations from serious infectious diseases, there is a considerable part of the population who oppose vaccinations. In particular, anti-vaccination perceptions, among travelers to countries with endemic diseases, are a major public health concern. Although hesitancy towards vaccinations is not a novel phenomenon, it came back to the forefront during the fight against the COVID-19 pandemic. This review explores the etiology of anti-vaccination beliefs among travelers and draws conclusions about their impact on public health and society in general. For this purpose, a purposeful search for data on the causative factors of vaccine hesitancy and their impact on people's health was conducted. A descriptive analysis of the findings and conclusions regarding possible implications in health policy and clinical practice are presented. A fear of side effects, lack of credence in the necessity of vaccines, and mistrust of medical authorities are important causative factors. Their interplay shapes hesitancy towards vaccines. However, anti-vaccination beliefs can also be an aspect of a more general unconventional stance of life. Health care professionals and organizations must be ready to tackle vaccine hesitancy by making the necessary interventions. Correcting misconceptions about vaccinations is a prerequisite for ensuring personal and public health, especially in the context of a pandemic or epidemic. Moreover, ensuring the efficacy and safety of vaccines, especially in cases of modern technology applications, is a fundamental factor in addressing people's concerns about vaccines. For this purpose, medical authorities and organizations must provide accurate and clear information on vaccines so as to eliminate misinformation. Furthermore, clinicians should cultivate their communication skills in order to convey the appropriate messages to prospective recipients of vaccinations.

Analyzing Best Practices for Pediatric Well-Child Clinic Visits in the United States for Children Aged Three to Five Years: A Review

Inadequate routine healthcare check-up visits for children aged three to five years impose substantial economic and social burdens due to morbidity and mortality. The absence of regular well-child visits and vaccinations leads to avoidable diseases, underscoring the need for a renewed emphasis on childhood immunizations and check-ups. Out of 160 articles initially screened after removing duplicates, 45 were chosen for full-text review following initial title and abstract screening by two independent reviewers. Afterward, 20 studies met the predefined inclusion criteria during the final assessment of full-text articles, and data were systematically extracted from these selected studies using standardized forms to ensure accuracy and consistency. Well-child visits promote holistic development, health, and well-being in children aged three to five years. Following established guidelines and evidence-based practices, healthcare professionals provide assessments, vaccinations, and guidance for a healthy future. Despite challenges, well-child visits are vital for preventive care, empowering informed decisions for children's growth and development. The benefits of well-child visits encompass growth monitoring, anticipatory guidance, and preventive measures, crucial for children with chronic illnesses. Key components include comprehensive assessments, developmental screenings, vision and hearing evaluations, immunizations, health education, and counseling. In the case of juvenile diabetes, parental education is paramount. Parents need to understand the intricacies of insulin administration, including proper dosage calculation based on glucose measurements, meal planning, and the importance of timing insulin injections. Implementing guidelines and principles by organizations such as Bright Futures and the American Academy of Pediatrics ensures holistic care, parent involvement, and evidence-based practices. This review explores best practices and guidelines for such visits, emphasizing their role in monitoring and promoting children's development.

Effect of psychological factors on COVID-19 vaccine hesitancy

BACKGROUND

Vaccine hesitancy can prevent full immunization against coronavirus infectious disease-19 (COVID-19). We hypothesized that multiple factors, including an individual's personality and psychological factors, are associated with vaccine hesitancy.

METHODS

A total of 275 non-vaccinated individuals were recruited for this study. Participants completed a self-report questionnaire including sociodemographic factors, health status, COVID-19 literacy and psychological factors (depressive symptoms, generalized anxiety, somatization, illness anxiety, temperament and character). In a hierarchical logistic regression analysis, a discrete set of hierarchical variables with vaccine acceptance or hesitancy as the dependent variable was added to the demographic factors for Model 1; Model 1 + health status for Model 2; Model 2 + COVID-19 literacy for Model 3 and Model 3 + psychological factors for Model 4.

RESULTS

Models 3 and 4 could predict vaccine hesitancy. High scores on the Generalized Anxiety Disorder-7 and the Illness Attitude Scale, low confidence, low collective responsibility and low reward dependence were risk factors for vaccine hesitancy.

CONCLUSIONS

The present study demonstrates that psychological factors play critical roles in vaccine hesitancy. In addition to conventional policies that emphasize COVID-19 vaccines' safety and efficacy and the collective benefits of vaccination, a more individualized approach that considers an individual's emotions and personality is necessary.

Understanding COVID-19 vaccine hesitancy in Pakistan: The paradigm of confidence, convenience, and complacency; A cross-sectional study

BACKGROUND AND OBJECTIVES

Vaccine hesitancy is a big obstacle for vaccination programs, as is anticipated for the COVID-19 vaccination program, resulting in low uptake of vaccines thereby hindering the process of reaching herd immunity. Bearing this in mind the current study was aimed to explore the determinants of vaccine hesitancy amongst the Pakistani population.

METHODOLOGY

A cross-sectional study was carried out from November 2020 to March 2021. The conceptual framework of the study was based on the 3Cs (Confidence, Convenience, Complacency) model. The google-forms-based questionnaire was disseminated amongst the general population. Data collected were entered into SPSS version 26 and analyzed.

RESULTS

Of the 421 participants, 68.4% were women. Non-healthcare workers were 55.8% of respondents. Of vaccine-hesitant individuals, 26.13% reported they were very unlikely to get vaccinated. Perception of COVID-19 vaccine was explored, which revealed 12.6% of individuals agreed the vaccine was not safe as it came out too fast, 50.6% were worried about experiencing side-effects, 18% believed the vaccine will not offer protection and 5.9% believed the vaccine would cause death. Low Practice of standard operating procedure (SOP) in non-Healthcare workers was the strongest contributor to vaccine hesitancy (OR: 5.338, p = 0.040, 95% CI: 1.082-26.330) followed by High complacency (p = 0.026) and Moderate Complacency (OR: 0.212, p = 0.007, 95% CI: 0.069-0.654) towards COVID-19 vaccination. In Healthcare workers the strongest contributor to vaccine hesitancy was having a Moderate Confidence (OR: 0.323, p = 0.042, 95% CI: 0.109-0.958) in the vaccine followed by Moderate Convenience (OR: 0.304, p = 0.049, 95% CI: 0.093-0.993) for vaccination.

CONCLUSION

Campaigning and communication strategies to reaffirm confidence in the COVID-19 vaccine and educating the general population about the vaccine could lead to increased perception of vaccine safety and effectiveness thereby restoring confidence in vaccine and decreasing vaccine hesitancy. Likewise, working to increase vaccine convenience and decreasing complacency towards the COVID-19 vaccine would translate into high vaccine uptake.

MESH WORDS

Vaccine hesitancy; vaccination intention, COVID-19 vaccine, vaccine confidence, complacency, convenience.

Predictive factors of hesitancy to vaccination against SARS-CoV-2 virus in young adults in Spain: Results from the PSY-COVID study

Widespread population vaccination against the SARS-CoV-2 virus is a matter of great interest to public health as it is the main pharmacological measure to contain the COVID-19 pandemic. Hesitancy/reluctance to vaccination has become a main barrier to containing the pandemic. Young adults are the age group with the greatest resistance to vaccination, even in countries with the highest vaccination rates during this pandemic. The objective of this study was to identify the main predictive factors of vaccination intention and profile people with hesitancy/reluctance to vaccinate against SARS-CoV-2 virus in young adults living in Spain during the pandemic. A cross-sectional study was conducted based on the administration of an online survey (PSY-COVID-2) that evaluated the intention of vaccination together with a wide range of sociodemographic, social, cognitive, behavioral and affective variables in a sample of 2210 young adults. 14% of the sample showed hesitancy/reluctance to vaccination at the beginning of their vaccination campaign. A total of 35 factors were associated (small to medium effect sizes) with the intention to get vaccinated. A reduced set of 4 attitudinal and social variables explained 41% of the variability in vaccination intention: attitude to the vaccination, trust in health staff/scientists, conspiracy beliefs about SARS-CoV-2 and time spent being informed about COVID-19. These variables showed good sensitivity/specificity for classifying people as reluctant/not reluctant to vaccination, properly classifying 86% of people. Psychosocial processes related to attitudes, trust and information are the main predictors of vaccination intention in a highly reluctant group such as the young adult population.

Measles vaccine uptake among Italian medical students compared to the pre-COVID-19 era

The COVID-19 pandemic has severely affected health systems worldwide and raised the issue of vaccine hesitancy. In 2022, the World Health Organization reported an outbreak of measles infection among people over 20 years of age in the European Region. Previous studies found low rates of measles immunization among Italian healthcare workers (HCWs) and medical students. Vaccine hesitancy is a relevant cause of low immunization rate among HCWs and the general population. We aim to evaluate the measles vaccine uptake among medical students of a large teaching hospital, compared to the pre-pandemic period. This is a retrospective observational study, that evaluated the immune status and the vaccine acceptance rate for measles in medical students at the University of Tor Vergata, Rome, who underwent occupational health surveillance from 1 January to 1 December 2022. We also compared the data with the results of a pre-pandemic survey conducted in 2018. Vaccine uptake among unprotected medical students was 59.5%. The data showed no significant difference in vaccine uptake compared with the pre-COVID-19 period. Conversely, the rate of serologically immune subjects to measles increased from 89.66% in 2018 to 97.45% in 2022 as a result of the recent mandatory vaccination policy. Despite efforts to tackle vaccine hesitancy during the COVID-19 pandemic, measles vaccine uptake is still low among young adults starting their medical training, and their compliance with free workplace vaccination offers is suboptimal. Occupational health services should raise awareness among workers and work together to implement strategies to achieve comprehensive measles vaccination coverage among occupational health workers.

Anti-Vaccination Attitude and Vaccination Intentions Against Covid-19: A Retrospective Cross-Sectional Study Investigating the Role of Media Consumption

Objective

The present study explores, retrospectively, the link between anti-vaccination attitude and vaccination intentions and extends this relationship to the effect of media consumption style on attitude.

Method

Generalized linear mixed-models were used to estimate vaccination intentions (related to each of the four available vaccines at the time of the survey) relying on anti-vaccination attitude measured using the Italian translation of the Vaccination Attitude Examination (VAX) scale. Multiple linear regression was used to estimate which media type and which consumption frequency were responsible for variation in the anti-vaccination attitude.

Results

Greater anti-vaccination attitude led to lower vaccination intention (b=-8.33, p<.0001) confirming the attitude-intention link. Crucially, consuming vaccination related information via printed press weekly (b=-0.74, p=.0001) or daily (b=-0.96, p<.0001) were the only protective factors against developing anti-vaccination attitudes. On the other hand, discussing vaccination with the family physician weekly (b=0.66, p=.002) or even daily (b=0.52, p=.026), and actively looking for vaccination related information on specialized websites and blogs every day (b=0.64, t=2.78, p=.006) were risk factors related to increased anti-vaccination attitude. No effects of social media on anti-vaccination attitude were found.

Conclusions

The results confirm that vaccination intentions can be linked to the underlying anti-vaccination attitude. Moreover, our results suggest that the web and the blog sphere, but not social media, are the most anti-vaccination fuelling media and that health practitioners engage with the most vaccination-hesitant individuals. Further interventions could leverage these insights to tackle the vaccination hesitancy issue.

Failure to Complete Multidose Vaccine Series in Early Childhood

BACKGROUND

Most early childhood immunizations require 3 to 4 doses to achieve optimal protection. Our objective was to identify factors associated with starting but not completing multidose vaccine series.

METHODS

Using 2019 National Immunization Survey-Child data, US children ages 19 to 35 months were classified in 1 of 3 vaccination patterns: (1) completed the combined 7-vaccine series, (2) did not initiate ≥1 of the 7 vaccine series, or (3) initiated all series, but did not complete ≥1 multidose series. Associations between sociodemographic factors and vaccination pattern were evaluated using multivariable log-linked binomial regression. Analyses accounted for the survey's stratified design and complex weighting.

RESULTS

Among 16 365 children, 72.9% completed the combined 7-vaccine series, 9.9% did not initiate ≥1 series, and 17.2% initiated, but did not complete ≥1 multidose series. Approximately 8.4% of children needed only 1 additional vaccine dose from 1 of the 5 multidose series to complete the combined 7-vaccine series. The strongest associations with starting but not completing multidose vaccine series were moving across state lines (adjusted prevalence ratio [aPR] = 1.45, 95% confidence interval [CI]: 1.18-1.79), number of children in the household (2 to 3: aPR = 1.29, 95% CI: 1.05-1.58; 4 or more: aPR = 1.68, 95% CI: 1.30-2.18), and lack of insurance coverage (aPR = 2.03, 95% CI: 1.42-2.91).

CONCLUSIONS

More than 1 in 6 US children initiated but did not complete all doses in multidose vaccine series, suggesting children experienced structural barriers to vaccination. Increased focus on strategies to encourage multidose series completion is needed to optimize protection from preventable diseases and achieve vaccination coverage goals.

The association between vaccine hesitancy and pertussis: a systematic review and meta-analysis

BACKGROUND

Robust routine immunization schedules for pertussis-containing vaccines have been applied for years, but pertussis outbreaks remain a worldwide problem. This study aimed to investigate the association between vaccine hesitancy and pertussis in infants and children.

METHODS

We searched PubMed, Cochrane, Web of Science, Embase, and China National Knowledge Internet for studies published between January 2012 and June 2022. This study included case-control and cohort studies that assessed the association between childhood/maternal vaccine hesitancy and odds ratios (ORs), risk ratios (RRs), and vaccine effectiveness (VE) related to pertussis in infants and children [Formula: see text] 9 years old. ORs/VEs with a 95% confidence interval (CI) were calculated. Random-effects meta-analysis models were used for appropriate pooled estimates, and heterogeneity was assessed using [Formula: see text]. Cumulative meta-analysis and subgroup analyses stratified by study characteristics were performed.

RESULTS

Twenty-two studies were included, with a mean quality score of 7.0 (range 6.0-9.0). Infants and children with pertussis were associated with higher vaccine hesitancy to all doses (OR = 4.12 [95% CI: 3.09-5.50]). The highest OR was between children who were unvaccinated over four doses and children who were fully vaccinated (OR = 14.26 [95%CI: 7.62-26.70]); childhood vaccine delay was not statistically significantly associated with pertussis risk (OR = 1.18 [95% CI: 0.74-1.89]). Maternal vaccine hesitancy was associated with significantly higher pertussis risk in infants aged 2 and 3 months old, with higher pertussis ORs in infants [Formula: see text] 2 months old (OR = 6.02 [95%CI: 4.31-8.50], OR = 5.14 [95%CI: 1.95-13.52] for infants [Formula: see text] 2 and [Formula: see text] 3 months old, respectively). Maternal and childhood VEs were high in reducing pertussis infection in infants and children. The administration time of maternal vaccination had little effect on VE.

CONCLUSION

Vaccine hesitancy increased pertussis risks in infants and children. Ensuring that children receive up-to-date pertussis vaccines is essential; short delays in receiving childhood vaccinations may be unimportant. Maternal vaccinations for pertussis should be encouraged.

Development of a novel instrument for assessing intentional non-adherence to official medical recommendations (iNAR-12): a sequential mixed-methods study in Serbia

OBJECTIVES

We aimed to (1) develop a novel instrument, suitable for the general population, capturing intentional non-adherence (iNAR), consisting of non-adherence to prescribed therapy, self-medication and avoidance of seeking medical treatment; (2) differentiate it from other forms of non-adherence, for example, smoking; and (3) relate iNAR to patient-related factors, such as sociodemographics, health status and endorsement of irrational beliefs (conspiratorial thinking and superstitions) and to healthcare-related beliefs and experiences ((mis)trust and negative experiences with the healthcare system, normalisation of patient passivity).

DESIGN

То generate iNAR items, we employed a focus group with medical doctors, supplemented it with a literature search and invited a public health expert to refine it further. We examined the internal structure and predictors of iNAR in an observational study.

SETTING

Data were collected online using snowball sampling and social networks.

PARTICIPANTS

After excluding those who failed one or more out of three attention checks, the final sample size was n=583 adult Serbian citizens, 74.4% female, mean age 39.01 years (SD=12.10).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary, planned outcome is the iNAR Questionnaire, while smoking was used for comparison purposes.

RESULTS

Factor analysis yielded a one-factor solution, and the final 12-item iNAR Questionnaire had satisfactory internal reliability (alpha=0.72). Health condition and healthcare-related variables accounted for 14% of the variance of iNAR behaviours, whereas sociodemographics and irrational beliefs did not additionally contribute.

CONCLUSIONS

We constructed a brief yet comprehensive measure of iNAR behaviours and related them to health and sociodemographic variables and irrational beliefs. The findings suggest that public health interventions should attempt to improve patients' experiences with the system and build trust with their healthcare practitioners rather than aim at specific demographic groups or at correcting patients' unfounded beliefs.

STUDY REGISTRATION

The design and confirmatory analyses plan were preregistered (https://osf.io/pnugm).

Attitudes and Values of US Adults Not Yet Up-to-Date on COVID-19 Vaccines in September 2022

(1) Background: Periodic resurgences in COVID-19 due to more contagious variants highlight the need to increase coverage of booster doses. (2) Methods: Our September 2022 nationally representative survey of US adults measured COVID-19 vaccination status, intentions, attitudes, values, and confidence in information sources. (3) Findings: Although 85% of the weighted sample reported receiving at least one dose of a COVID-19 vaccine, only 63% reported being up-to-date on COVID-19 vaccines (e.g., received a booster dose). Only 12% of those not yet up-to-date indicated they were likely to get up-to-date as soon as possible, whereas 42% were unlikely to ever get up-to-date, and 46% were still uncertain. Most of those not up-to-date on their COVID-19 vaccines were under 45 years of age (58%), without a bachelor's degree (76%), making under $75,000 annually (53%), and Republican or Independent (82%). Prevalent concerns about COVID-19 vaccines among those uncertain about getting up-to-date included: potential side effects that have not been figured out yet (88%), speed of development (77%), newness (75%), ingredients (69%), drug companies making money (67%), allergic reactions (65%), and experimenting on people (63%). (4) Conclusions: Nearly half of adults not yet up-to-date on COVID-19 vaccines were uncertain about doing so, indicating an opportunity to support their decision-making.

COVID-19 Vaccine Hesitancy among Patients Recovered from COVID-19 Infection in Wuhan, China: A Cross-Sectional Questionnaire Study

BACKGROUND

Although patients recovered from COVID-19 infection already have immunity gained from natural infection, they are still at risk of reinfection due to the emergence of new variants of COVID-19 and the diminishing of naturally acquired immunity. COVID-19 vaccine is associated with efficacious protection against COVID-19 infection and could boost infection-acquired immunity, however, certain amounts of COVID-19 survivors have not been vaccinated due to vaccine hesitancy.

OBJECTIVE

The current study aimed to investigate COVID-19 vaccine hesitancy and related factors among COVID-19 survivors.

METHODS

A cross-sectional questionnaire survey was conducted among patients recovered from COVID-19 infection in Wuhan, China between June 10 and July 25, 2021. Questionnaire included sociodemographic information, items on COVID-19 infection, the COVID-19 vaccine hesitancy scale based on the 3Cs' model, trust in vaccine manufacturers and health facilities, and reasons for the decision to COVID-19 vaccination. Multiple logistic regression analysis was used to assess the influenced factors of COVID-19 vaccine hesitancy.

RESULTS

Among 1422 participants, 538 (37.8%) were not vaccinated against COVID-19. COVID-19 recovered patients who perceived current unhealthy status had more hesitancy about COVID-19 vaccine than those who perceived themselves healthy (OR 0.45, 95% CI 0.28-0.71). Compared to the asymptomatic patients, patients with mild symptoms were more likely to receive COVID-19 vaccine (OR 1.67, 95% CI 1.02-2.82). Regarding the 3Cs' model, high complacency and low convenience were significant negative factors for COVID-19 vaccination (P<.05). Trust in vaccine manufacturers and health facilities was a significant positive factor for COVID-19 vaccination (OR 1.14, 95% CI 1.09-1.19). "Self-needs" was the main reason for patients to receive the COVID-19 vaccine; "already have antibodies and do not need vaccination" was the main reason for patients not to receive the COVID-19 vaccine.

CONCLUSIONS

Among the three major factors of vaccine hesitancy, complacency was proved the most notable one among COVID-19 recovered patients, educational campaigns can focus on raising the awareness of risk of infection and the benefits of vaccination to reduce complacency toward vaccination among them. For COVID-19 recovered patients, improving factors related to convenience such as transportation and environment of vaccination and proving door-to-door service were also necessary to facilitate their vaccination. In addition, addressing the concerns about vaccination of COVID-19 recovered patients could foster trust and promote their vaccination.

CLINICALTRIAL

Exploring the vaccine conversation on TikTok in Italy: beyond classic vaccine stances

TikTok, a social media platform for creating and sharing short videos, has seen a surge in popularity during the COVID-19 pandemic. To analyse the Italian vaccine conversation on TikTok, we downloaded a sample of videos with a high play count (Top Videos), identified through an unofficial Application Programming Interface (consistent with TikTok's Terms of Service), and collected public videos from vaccine sceptic users through snowball sampling (Vaccine Sceptics' videos). The videos were analysed using qualitative and quantitative methods, in terms of vaccine stance, tone of voice, topic, conformity with TikTok style, and other characteristics. The final datasets consisted of 754 Top Videos (by 510 single users) plus 180 Vaccine Sceptics' videos (by 29 single users), posted between January 2020 and March 2021. In 40.5% of the Top Videos the stance was promotional, 33.9% were indefinite-ironic, 11.3% were neutral, 9.7% were discouraging, and 3.1% were ambiguous (i.e. expressing an ambivalent stance towards vaccines); 43% of promotional videos were from healthcare professionals. More than 95% of the Vaccine Sceptic videos were discouraging. Multiple correspondence analysis showed that, compared to other stances, promotional videos were more frequently created by healthcare professionals and by females, and their most frequent topic was herd immunity. Discouraging videos were associated with a polemical tone of voice and their topics were conspiracy and freedom of choice. Our analysis shows that Italian vaccine-sceptic users on TikTok are limited in number and vocality, and the large proportion of videos with an indefinite-ironic stance might imply that the incidence of affective polarisation could be lower on TikTok, compared to other social media, in the Italian context. Safety is the most frequent concern of users, and we recorded an interesting presence of healthcare professionals among the creators. TikTok should be considered as a medium for vaccine communication and for vaccine promotion campaigns.

A cultural evolutionary model of the interaction between parental beliefs and behaviors, with applications to vaccine hesitancy

Health perceptions and health-related behaviors can change at the population level as cultures evolve. In the last decade, despite the proven efficacy of vaccines, the developed world has seen a resurgence of vaccine-preventable diseases (VPDs) such as measles, pertussis, and polio. Vaccine hesitancy, an individual attitude influenced by historical, political, and socio-cultural forces, is believed to be a primary factor responsible for decreasing vaccine coverage, thereby increasing the risk and occurrence of VPD outbreaks. Behavior change models have been increasingly employed to understand disease dynamics and intervention effectiveness. However, since health behaviors are culturally influenced, it is valuable to examine them within a cultural evolution context. Here, using a mathematical modeling framework, we explore the effects of cultural evolution on vaccine hesitancy and vaccination behavior. With this model, we shed light on facets of cultural evolution (vertical transmission, community influences, homophily, etc.) that promote the spread of vaccine hesitancy, ultimately affecting levels of vaccination coverage and VPD outbreak risk in a population. In addition, we present our model as a generalizable framework for exploring cultural evolution when humans' beliefs influence, but do not strictly dictate, their behaviors. This model offers a means of exploring how parents' potentially conflicting beliefs and cultural traits could affect their children's health and fitness. We show that vaccine confidence and vaccine-conferred benefits can both be driving forces of vaccine coverage. We also demonstrate that an assortative preference among vaccine-hesitant individuals can lead to increased vaccine hesitancy and lower vaccine coverage.

Evaluating COVID-19 vaccination intentions and vaccine hesitancy among parents of children with autism spectrum disorder

As the global vaccination mass campaign against COVID-19 extended to children aged 5 to 11 years, some parents remained hesitant about their children being administered the vaccine despite data supporting its safety. Parent vaccine hesitancy (PVH) may have predisposed certain groups of children, particularly those with autism spectrum disorder (ASD), to COVID-19 when other neurotypical children would have been vaccinated. We investigated the current PVH in 243 parents of children with ASD and 245 controls using the Parent Attitudes about Childhood Vaccines (PACV) scale. The study was conducted in Qatar from May to October 2022. Overall, 15.0% [95% CI 11.7%; 18.3%] of parents were vaccine-hesitant, with no difference (p = 0.054) between groups (ASD children [18.2%] vs. controls [11.7%]). The only sociodemographic factor associated with higher vaccine hesitancy was being a mother (as compared to being a father). The COVID-19 vaccine receipt rate at the time of the study did not differ between ASD (24.3%) and non-ASD groups (27.8%). Around two-thirds of parents of children with ASD refused or were unsure about vaccinating their children against COVID-19. We found that the intent to vaccinate against COVID-19 was higher in parents who were married and in those with a lower PACV total score. Continued public health efforts are needed to address vaccine hesitancy among parents.

Spatial distribution and determinants of childhood vaccination refusal in the United States

Parental refusal and delay of childhood vaccination has increased in recent years in the United States. This phenomenon challenges maintenance of herd immunity and increases the risk of outbreaks of vaccine-preventable diseases. We examine US county-level vaccine refusal for patients under five years of age collected during the period 2012-2015 from an administrative healthcare dataset. We model these data with a Bayesian zero-inflated negative binomial regression model to capture social and political processes that are associated with vaccine refusal, as well as factors that affect our measurement of vaccine refusal. Our work highlights fine-scale socio-demographic characteristics associated with vaccine refusal nationally, finds that spatial clustering in refusal can be explained by such factors, and has the potential to aid in the development of targeted public health strategies for optimizing vaccine uptake.

Views and Challenges of COVID-19 Vaccination in the Primary Health Care Sector. A Qualitative Study

COVID-19 has affected the global community as it has severely raised population mortality and morbidity rates. Vaccination was seen as a mechanism against the spread of the pandemic. Yet, there are still several reservations about its adoption. Professionals in the field of health care have a crucial frontline role. The present study uses a qualitative research approach to examine Greek health professionals' views on vaccination acceptance. According to the key findings, health professionals largely accept vaccination. The main reasons cited were scientific knowledge, a sense of obligation to society, and protection from disease. However, there are still numerous restrictions to adhering to it. This is due to the lack of knowledge of certain scientific disciplines or to misinformation, as well as to religious or political convictions. The issue of trust is central to the acceptance of vaccinations. According to our research, the most adequate strategy to enhance immunization and ensure that it is widely accepted is to promote health educational interventions for professionals working in primary care settings.

Reduced antiviral seropositivity among patients with inflammatory bowel disease treated with immunosuppressive agents

BACKGROUND

Although live-attenuated vaccines are contraindicated under immunosuppression, the immune status of patients with inflammatory bowel disease (IBD) has not been fully assessed prior to immunosuppressive therapy.

AIMS

To investigate antiviral serostatus against viruses requiring live vaccines for prevention in IBD patients undergoing immunosuppressive therapy.

METHODS

This multicenter study included IBD patients who were aged <40 years and were treated with thiopurine monotherapy, molecular-targeted monotherapy, or combination therapy. Gender- and age-matched healthy subjects (HS) living in the same areas were included as control group. Antibody titers against measles, rubella, mumps, and varicella were measured by enzyme-linked immunosorbent assays.

RESULTS

A total of 437 IBD patients (163 ulcerative colitis [UC] and 274 Crohn's disease [CD]) and 225 HS were included in the final analysis. Compared with HS, IBD patients had lower seropositivity rates for measles (IBD vs. HS = 83.91% vs. 85.33%), rubella (77.55% vs. 84.89%), mumps (37.50% vs. 37.78%), and varicella (91.26% vs. 96.44%). Gender- and age-adjusted seropositivity rates were lower in UC patients than in both CD patients and HS for measles (UC, CD, and HS = 81.60%, 85.29%, and 85.33%), rubella (76.40%, 78.23%, and 84.89%), mumps (27.16%, 43.70%, and 37.78%), and varicella (90.80%, 91.54%, and 96.44%); the difference was significant for all viruses except measles. Divided by the degree of immunosuppression, there were no significant differences in seropositivity rates among IBD patients.

CONCLUSIONS

IBD patients, especially those with UC, exhibit reduced seropositivity rates and may benefit from screening prior to the initiation of immunosuppressive therapy.

Using the 5C model to understand COVID-19 vaccine hesitancy across a National and South Carolina sample

Vaccine hesitancy is a serious threat to global health; however, significant COVID-19 vaccine hesitancy exists throughout the United States. The 5C model, which postulates five person-level determinants for vaccine hesitancy - confidence, complacency, constraints, risk calculation, and collective responsibility - provides one theoretical way of understanding COVID-19 vaccine hesitancy. The present study examined the effects of these 5C drivers of vaccine behavior on early vaccine adoption and vaccine intentions above and beyond theoretically salient demographic characteristics and compared these associations across a National sample (n = 1634) and a statewide sample from South Carolina (n = 784) - a state with documented low levels of COVID-19 vaccination uptake. This study used quantitative and qualitative data collected in October 2020 to January 2021 from the MFour-Mobile Research Panel, a large, representative non-probability sample of adult smartphone users. Overall, the South Carolina sample reported lower COVID-19 vaccine intentions and higher levels of 5C barriers to vaccine uptake compared to the National sample. Findings further indicated that both demographic characteristics (race) and certain drivers of vaccine behavior (confidence and collective responsibility) are associated with vaccine trust and intentions across samples above and beyond other variables. Qualitative data indicated that COVID-19 vaccine hesitancy was driven by fears about the quick vaccine development, limited research, and potential side effects. Although there are some limitations to the cross-sectional survey data, the present study offers valuable insight into factors associated with early COVID-19 vaccine hesitancy across the United States.

Acceptance and hesitancy to receive COVID-19 vaccine among university students in Egypt: a nationwide survey

BACKGROUND

The public's willingness to be vaccinated will determine the success of the COVID-19 vaccination program. The aim of this study was to identify acceptance and hesitancy to receive COVID-19 vaccine among university students in Egypt, assess their level of knowledge about COVID-19 vaccine and identify factors that influence their intention towards COVID-19 vaccination.

METHODS

A standardized and self-administered questionnaire was distributed among university students allover Egypt. The questionnaire included sociodemographic data, intention to receive COVID-19 vaccine, knowledge and beliefs about it and status of COVID-19 vaccination. Logistic regression analysis was used to determine factors associated with COVID-19 vaccine acceptancy.

RESULTS

A total of 1071 of university students were involved, with a mean age of 20.51 years (SD = 1.66) and 68.2% were females. COVID-19 vaccination acceptability rate was 69.0% while hesitancy was 20.8% and resistancy was 10.2%. Median knowledge score of 4 out of 8 (IQR = 8). The main motivation for vaccine acceptance was fear of being infected (53.6%) and desire to get back to normal life (51.0%) while the main barriers against getting vaccinated were being afraid of serious side effects. Univariate regression analysis revealed an increasing likelihood of vaccine acceptancy associated with an active lifestyle (OR 1.35, 95% CI 1.04-1.75, p = 0.025), a high knowledge score (OR 1.53, 95% CI 1.42-1.66, p < 0.001), and positive vaccine beliefs.

CONCLUSION

There is a high rate of acceptability of COVID-19 vaccination among university students. Vaccine acceptability is associated with an active lifestyle, a high knowledge score and positive vaccine beliefs. Educational campaigns and efforts aiming to raise awareness about safety and efficacy of COVID-19 vaccines need to be directed to this important population.

Evaluation of the effectiveness of maternal immunization against pertussis in Alberta using agent-based modeling: A Canadian immunization research network study

INTRODUCTION

The re-emergence of pertussis has occurred in the past two decades in developed countries. The highest morbidity and mortality is seen among infants. Vaccination in pregnancy is recommended to reduce the pertussis burden in infants.

METHODS

We developed and validated an agent-based model to characterize pertussis epidemiology in Alberta. We computed programmatic effectiveness of pertussis vaccination during pregnancy (PVE) in relation to maternal vaccine coverage and pertussis disease reporting thresholds. We estimated the population preventable fraction (PFP) of different levels of maternal vaccine coverage against counterfactual "no-vaccination" scenario. We modeled the effect of immunological blunting and measured protection through interruption of exposure pathways.

RESULTS

PVE was inversely related to duration of passive immunity from maternal immunization across most simulations. In the scenario of 50% maternal vaccine coverage, PVE was 87% (95% quantiles 82-91%), with PFP of 44% (95% quantiles 41-45%). For monthly age intervals of 0-2, 2-4, 4-6 and 6-12, PVE ranged between 82 and 99%, and PFP ranged between 41 and 49%. At 75% maternal vaccine coverage, PVE and PFP were 90% (95% quantiles 86-92%) and 68% (95% quantiles 65-69%), respectively. At 50% maternal vaccine coverage and 10% blunting, PVE and PFP were 86% (95% quantiles 77-87%) and 43% (95% quantiles 39-44%), respectively, while at 50% blunting, the corresponding values of PVE and PFP were 76% (95% quantiles 70-81%) and 38% (95% quantiles 35-40%). PVE attributable to interruption of exposure pathways was 54-57%.

CONCLUSIONS

Our model predicts significant reduction in future pertussis cases in infants due to maternal vaccination, with immunological blunting slightly moderating its effectiveness. The model is most sensitive to maternal vaccination coverage. The interruption of exposure pathways plays a role in the reduction of pertussis burden in infants due to maternal immunization. The effect of maternal immunization on population other than infants remains to be elucidated.