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Background: Sexually transmitted infections (STIs) like chlamydia, gonorrhea, syphilis, and trichomoniasis contribute significantly to global morbidity and mortality. Researchers are pursuing vaccines for these STIs, and a clinical trial is currently underway for a chlamydia vaccine. However, there is little research available on individuals' willingness to receive chlamydia, gonorrhea, syphilis, and trichomoniasis vaccines. The purpose of this analysis was to map the existing literature we have on individuals' willingness to receive these bacterial/parasitic STI vaccines and understand what information on vaccine acceptability is still needed., Methods: We searched seven databases for literature on STI vaccine acceptability, then conducted title/abstract and full-text reviews to assess eligibility. All reviews and abstractions were conducted blindly by two reviewers, with discrepancies settled by discussion or the input of a third reviewer., Results: Eight of the original 2,259 texts of interest met inclusion criteria. After data abstraction, we found that gonorrhea was the most commonly examined, followed by chlamydia and syphilis. Trichomoniasis vaccine acceptability was not reported. Most texts reported high acceptability, but there did not appear to be data describing how vaccine characteristics affect acceptability. Similarly, while the literature covers a variety of populations, most of the study populations were based out of the United States or Canada and were patrons of healthcare facilities or participants from a larger health intervention study. Therefore, more information is needed on populations outside North America, and on groups with lower healthcare access and utilization., Conclusion: As the incidence of bacterial and parasitic STIs increase, and as we grow nearer vaccines for these illnesses, understanding how likely the public is to accept and receive these vaccines is crucial to their success. While the existing literature describes STI vaccine acceptability in a variety of populations, their overall number is small. More research into STI vaccine acceptability outside of North America, and especially examining how factors like number of doses, timing, and cost influence vaccine acceptability is needed to ensure effective future vaccine rollouts., (© 2023. The Author(s).)

Widespread uptake of a future gonorrhea vaccine could decrease the burden of disease and limit the spread of antibiotic resistance. However, gonorrhea vaccination will occur in the backdrop of the roll-out of the coronavirus disease 2019 (COVID-19) vaccine, which could have influenced parental perceptions about other, non-COVID-19 vaccines. In an internet-based cross-sectional survey, 74% of parents would get a gonorrhea vaccine for their child, and this was higher among those whose trust in pharmaceutical companies increased since the start of the COVID-19 pandemic. About 60% of adults aged 18 to 45 would receive a vaccine for themselves., Competing Interests: Disclosure The authors report no disclosures. The authors declare no conflicts of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Importance: COVID-19 vaccination rates in the US remain below optimal levels. Patient preferences for different attributes of vaccine products and the vaccination experience can be important in determining vaccine uptake decisions., Objective: To assess preferences for attributes of adult and pediatric COVID-19 vaccination among US adults., Design, Setting, and Participants: An online survey of a national panel of 1040 US adults was conducted in May and June 2021. A discrete choice analysis was used to measure the relative value of each attribute in the decision to choose a COVID-19 vaccination option for adults or children. Six attributes were used to described hypothetical vaccination options: vaccine effectiveness, mild side effects, rare adverse events, number of doses, time required for vaccination, and regulatory approval. Respondents chose between hypothetical vaccination profiles or no vaccination. Additional survey questions asked about vaccination beliefs, COVID-19 illness experience, COVID-19 risk factors, vaccination status, and opinions about the risk of COVID-19., Exposures: Respondents chose which vaccine profile they would prefer to receive for themselves (or no vaccination). Respondents then considered an identical set of profiles for a hypothetical child aged 0 to 17 years., Main Outcomes and Measures: Relative value of vaccination-related attributes were estimated using Bayesian logit regression. Preference profiles for subgroups were estimated using latent class analyses., Results: A total of 1040 adults (610 [59%] female; 379 participants [36%] with an age of 55 years and older years) responded to the survey. When asked about vaccination choices for themselves, participants indicated that vaccine effectiveness (95% vs 60%) was a significant attribute (β, 9.59 [95% CrI, 9.20-10.00] vs β, 0.41 [95% CrI, 0-0.80]). Respondents also preferred fewer rare adverse events (β, 6.35 [95% CrI, 5.74-6.86), fewer mild side effects (β, 5.49; 95% CrI, 5.12-5.87), 1 dose (β, 5.41; 95% CrI, 5.04-5.78), FDA approval (β, 6.01; 95% CrI, 5.64-6.41), and shorter waiting times (β, 5.67; 95% CrI, 4.87-6.48). Results were very similar when framing the question as adult or child vaccination, with slightly stronger preference for fewer rare adverse events for children. Latent class analysis revealed 4 groups of respondents: (1) individuals sensitive to safety and regulatory status, (2) individuals sensitive to convenience, (3) individuals who carefully considered all attributes in making their choices, and (4) individuals who rejected the vaccine., Conclusions and Relevance: In this survey study of US adults, the identification of 4 distinct preference groups provides new information to guide communications to support vaccine decision making. In particular, the group that prioritize convenience (less time required for vaccination and fewer doses) may present an opportunity to create actionable strategies to increase vaccination uptake for both adult and pediatric populations.

Background: Achieving COVID-19 community protection (aka, herd immunity) in China may be challenging because many individuals remain unsure or are unwilling to be vaccinated. One potential means to increase COVID-19 vaccine uptake is to essentially mandate vaccination by using existing mobile technologies that can prohibit unvaccinated individuals from certain public spaces. The "Health Code" is a ubiquitous mobile phone app in China that regulates freedom of travel based on individuals' predicted risk of exposure to SARS-CoV-2. Green-colored codes indicate ability to travel unrestricted in low-risk regions; yellow-colored codes indicate prohibition from major public spaces and modes of public transportation. We examined the effects of a "Health Code"-based vaccine mandate on willingness to vaccinate for COVID-19 in China., Methods: In August 2020, an online discrete choice experiment (DCE) was conducted among adults living in China. Participants completed up to six DCE choice sets, each containing two hypothetical COVID-19 vaccination scenario choices and a "do not vaccinate" choice. Half of the choice sets had a "Health Code" attribute that associated the "do not vaccinate" choice with a yellow Health Code implying restricted travel. Weighted, mixed effects multinomial logit regression was used to estimate preference utilities and predicted choice probabilities., Results: Overall, 873 participants completed 4317 choice sets. Most participants attained at least college-level education (90.9%). 29.8% of participants were identified as vaccine hesitators (defined as being unsure or unwilling to receive a COVID-19 vaccination). With and without the "Health Code"-based vaccine mandate, there was an 8.6% (85% CI: 6.4% - 10.92%) and 17.3% (85% CI:13.1% - 21.6%) respective predicted probability that vaccine hesitators would choose "do not vaccinate" over a common vaccination scenario currently in China (i.e., free, domestic vaccine, 80% effectiveness, 10% probability of fever side-effects, administered in a large hospital, two doses). Corresponding predicted probabilities for people who did not express vaccine hesitancy was 0.3% (93% CI: 0.0% - 14.3%) and 3.5% (93% CI:2.3% - 4.8%). The "Health Code"-based mandate significantly increased willingness to vaccinate when vaccine efficacy was greater than 60%., Conclusion: Among vaccine hesitators with higher educational attainment, willingness to vaccinate for COVID-19 appears to increase if mobile technology-based vaccine mandates prohibit unvaccinated individuals from public spaces and public transportation. However, such mandates may not increase willingness if perceived vaccine efficacy is low., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Vaccine hesitancy-the delay or refusal of vaccines despite their availability-has been linked to lower vaccination rates and outbreaks of vaccine-preventable diseases. Using cross-sectional surveys of 78,725 parents and other family members in the United States, Nguyen et al. (Am J Epidemiol. 2022;191(9):1626-1635) calculated the population attributable fraction (PAF) of vaccine hesitancy on nonreceipt of recommended childhood vaccines, including influenza vaccine. The PAF is readily calculated: p(rr - 1)/rr, where p is the proportion of those hesitant among nonvaccinated individuals, and rr is the risk ratio of nonvaccination between those hesitant over those nonhesitant. By vaccine, the PAF ranged from 6.5% for nonreceipt of the hepatitis B vaccine birth dose to 31.3% for nonreceipt of the diphtheria-tetanus-pertussis vaccine dose 3. For nonreceipt of influenza vaccine, the PAF varied geographically, with relatively high values in some Northeast (e.g., New York at 22.6%) and Northwest (e.g., Oregon at 23.0%) states and lower values in certain Southern (e.g., Louisiana at 7.5%) and Mountain West (e.g., Utah at 8.8%) states. The PAF can elucidate the contribution of vaccine hesitancy on nonvaccination in different circumstances. Future studies can apply this technique in different populations and incorporate different measures of vaccine hesitancy., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

It is important to distinguish between apprehensions that lead to vaccine rejection and those that do not. In this study, we (1) identifed latent classes of individuals by vaccination attitudes, and (2) compared classes of individuals by sociodemographic characteristics COVID-19 vaccination, and risk reduction behaviors. The COVID-19 Coping Study is a longitudinal cohort of US adults aged ≥ 55 years (n = 2358). We categorized individuals into three classes based on the adult Vaccine Hesitancy Scale using latent class analysis (LCA). The associations between class membership and sociodemographic characteristics, COVID-19 vaccination, and other behaviors were assessed using chi-square tests. In total, 88.9% were Vaccine Acceptors, 8.6% were Vaccine Ambivalent, and 2.5% Vaccine Rejectors. At the end, 90.7% of Acceptors, 62.4% of the Ambivalent, and 30.7% of the Rejectors had been vaccinated. The Ambivalent were more likely to be Black or Hispanic, and adopted social distancing and mask wearing behaviors intermediate to that of the Acceptors and Rejectors. Targeting the Vaccine Ambivalent may be an efficient way of increasing vaccination coverage. Controlling the spread of disease during a pandemic requires tailoring vaccine messaging to their concerns, e.g., through working with trusted community leaders, while promoting other risk reduction behaviors., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Rapidly urbanizing communities in middle-income countries could be sources of vaccine hesitancy, and may create hot spots of low vaccination coverage. This study characterizes vaccine hesitancy in Shanghai and identifies disparities in vaccine safety and efficacy concerns by residency status-a marker for recent migration into the city., Methods: Parents of children aged ≤18 years from immunization clinics in Shanghai were enrolled in summer 2019, with the data analyzed during winter 2019-2020. The paper questionnaire used the Parental Attitudes towards Childhood Vaccines scale, which included questions about vaccine safety and efficacy concerns. The primary independent variable was residency-whether an individual was a Shanghai local or a recent migrant (i.e., non-local). Linear regression models assessed the relationship between residency and vaccine safety and efficacy concerns., Results: Among 1,021 participants, 65.4% had local residency, and the remainder were urban non-locals (13.1%) or rural non-locals (21.5%). A majority of parents expressed concerns about vaccine side effects (73.8%), vaccine safety (63.9%), and vaccine effectiveness (52.4%). Compared with locals, rural non-locals were more concerned about vaccine side effects (β=0.26, 95% CI=0.07, 0.46), vaccine safety (β=0.42, 95% CI=0.19, 0.65), and vaccine effectiveness (β=0.37, 95% CI=0.16, 0.58)., Conclusions: Differences in vaccine hesitancy by residency could lead to geographical and sociodemographic disparities in vaccination coverage and outbreaks of vaccine-preventable disease., Supplement Information: This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health., (Copyright © 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Background: A clinical trial is ongoing to evaluate the safety and efficacy of a monkeypox vaccine among healthcare workers (HCWs). The critical question that needs to be addressed is whether HCWs are willing to accept and purchase this vaccine. The objective of this study was to evaluate the acceptance and willingness to pay (WTP) for the vaccine among HCWs., Methods: From May to July 2019, a cross-sectional study was conducted among registered general practitioners (GPs) in Indonesia. A contingent valuation method was employed to evaluate the WTP. Besides acceptance and WTP, various explanatory variables were also collected and assessed. A logistic regression and a multivariable linear regression were used to explore the explanatory variables influencing acceptance and WTP, respectively., Results: Among 407 respondents, 391 (96.0%) expressed acceptance of a free vaccination. The mean and median WTP was US$ 37.0(95%CI:US$ 32.76-US$ 41.23) and US$ 17.90(95%CI:US$ 17.90-US$ 17.90), respectively. In an unadjusted analysis, those 30 years old or younger had 2.94 times greater odds of vaccine acceptance compared to those who were older (95%CI: 1.07-8.08). Location of alma mater, type of workplace, length of individual medical experience, and monthly income of GPs were all significantly associated with WTP., Conclusion: Although the vast majority of GPs would accept a freely provided vaccine, they were also somewhat price sensitive. This finding indicates that partial subsidy maybe required to achieve high vaccine coverage, particularly among GPs at community health centres or those with a shorter duration of medical practice., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

It is not clear what kind of preferences parents in China would have for vaccines that could be added to a future immunization schedule. This study's aim was to assess Chinese parents' preferences for attributes of vaccines. We surveyed parents of young infants ≤3 months of age at immunization clinics in Shanghai, China, in 2017. We used a discrete choice experiment (DCE) to present parents with choices between two hypothetical profiles of vaccines which were described using the following attributes: cost, risk of side effect, location of vaccine manufacturer, vaccine testing, vaccine effectiveness, severity of disease, disease prevalence. A logistic regression output estimates of preference utilities. In total, 599 caregivers completed the DCE. Parents expressed lower preference for vaccines with a 30% chance of fever as an adverse event vs a 10% chance (OR: 0.53, 95% CI: 0.44, 0.64), for vaccines only 85% effective vs those 95% effective (OR: 0.55, 95% CI: 0.48, 0.62), and for imported vaccines (OR: 0.74, 95% CI: 0.60, 0.92) and those not tested in Chinese children (OR: 0.45, 95% CI: 0.37, 0.53) compared to domestic vaccines. More affluent groups preferred more expensive vaccines whereas less affluent groups did not express cost-based preferences. Promotion of vaccines in China should focus on parents' stated preferences, which include past testing done in Chinese children - which is, in fact, required of all licensed vaccines in China. Information about these trials could emphasize low risk of adverse events and high effectiveness., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objectives : China has made remarkable achievements in the field of immunization. However, several widespread vaccine safety-related events have recently received worldwide attention and reflect flaws in vaccine management. This study aimed to summarize vaccine safety-related events between 1985 and 2018 in China and analyze the profit motives of these events. Methods . Literature and media reviews were conducted to discover vaccine safety-related events. We developed a conceptual model with profit-related variables, and using information available from each event, we identified which profit-related variable was implicated, and how it related to the pursuit of higher profits. Results : A total of 39 vaccine safety-related events were found in vaccine production, procurement, transportation, and daily management, along with adverse events following immunization (AEFIs). Overall, 90% (35/39) of the events could be classified as profit-driven. The motives of most events could be tied to one or more reasons, including decreasing costs among vaccine producers (67%, 26/39), reducing actual procurement price (67%, 26/39), and reducing costs of transportation and/or cold chain (24/39, 62%). Conclusions : In order to deal with vaccine-related challenges, a more restrictive supervision system on vaccine production and more emergency preparedness, including health and risk communication strategies, for vaccine safety should be implemented.

Morbidity from vaccine-preventable diseases is high in India, but precise estimates of vaccination timeliness are difficult to compute because many children lack records of vaccination dates. This study assessed vaccination timeliness after accounting for right and left censoring of data. This cross-sectional study used the 2012-2013 District Level Household and Facility Survey in India. The outcome was vaccination timeliness for 9 vaccine doses: 1 dose Bacillus Calmette-Guérin (BCG), 4 doses oral polio vaccine, 3 doses diphtheria-pertussis-tetanus vaccine (DPT), and 1 dose measles-containing vaccine. Age-specific probabilities of vaccination were calculated using Turnbull estimators: children not yet vaccinated were right censored, and children vaccinated but without a recorded date were left censored. Data from 108,783 children under 5 years were available. For children 25-60 months, maternal recall was a more common source of information than a vaccination record with dates. At one month past the recommended vaccination age, estimated coverage ranged from 35% for DPT-3 to 55% for BCG. Accounting for censored data improved vaccination timeliness measures, and demonstrated little increase in vaccination coverage after age one. Efforts to reduce morbidity from vaccine-preventable diseases in India should focus on eliminating missed opportunities for vaccination and instituting special vaccination programs for older children., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background : Traditional measurements of vaccine coverage at specific ages can mask poor vaccine timeliness. However, optimal measurement of timing is unclear due to variations in countries' recommended vaccination schedules and lack of a commonly accepted standard for "timeliness". We conducted a systematic review of literature on vaccine timeliness and delay in low- and middle-income countries from 2007 to 2017. Methods : A search of articles published between January 1 2007 and December 31 2017, was performed in PubMed, EBSCOhost, and Embase. Results : 67 papers were included, of which 83% used a categorical measure of delay and 41% evaluated continuous delay. The most common age at assessment was 1 month, with earlier age benchmarks typically used with birth doses. Conclusions : Categorical definitions of vaccination timing vary widely, with benchmarks of delay varying from days to weeks to months. Use of a continuous measure of vaccine delay may be more informative and comparable.

Background: Vaccine hesitancy has been little studied in low- and middle-income countries but is a potential concern because vaccine refusal may increase the burden of infectious diseases and impede control efforts. The aim of this study was to compare vaccine hesitancy between locals, long-time city residents, and non-locals, who have more recently moved to the city from either other urban or rural areas, in Shanghai, China., Methods: Parents of infants ≤3 months of age were surveyed at immunization clinics in Shanghai, China. Participants completed a paper questionnaire utilizing the 10-item Vaccine Hesitancy Scale, which was developed by the World Health Organization Strategic Advisory Group of Experts on Immunization. Items were grouped based on internal consistency, and regressed onto demographic variables using a negative binomial model., Results: In total, 1,188 (92.5%) individuals participated. For most items on the scale, parents expressed positive beliefs about vaccines. However, about half of parents somewhat or strongly agreed that new vaccines carried more risks than older vaccines, and 71.6% somewhat or strongly agreed that they were concerned about serious adverse effects. Seven items from the Vaccine Hesitancy Scale were highly correlated and mapped onto "lack of confidence"; the other three items were analysed separately. Compared to mothers, fathers had less lack of confidence (β: -0.06, 95% CI: -0.12, -0.01), and individuals living in the outer suburbs (β: 0.13, 95% CI: 0.01, 0.25) and rural non-locals (β: 0.10, 95% CI: 0.02, 0.18) had greater lack of confidence in vaccines compared to their urban or local counterparts, respectively., Discussion: Shanghai parents professed confidence in certain vaccine benefits, but vaccine messaging could focus on addressing misconceptions about vaccines for diseases no longer common, newer vaccines, and adverse effects associated with vaccination. These messages may need to be separately tailored to locals and non-locals, who have differing concerns., Competing Interests: The authors have declared that no competing interests exist.

Background: China has reduced incidence of vaccine-preventable diseases through its Expanded Program on Immunization (EPI). Vaccines outside of the EPI are not provided for free by the government, however. This study explored how the stated importance of different disease and vaccine-related attributes interacted with beliefs about the immune system of a child to affect Chinese parents' decision to obtain a non-EPI vaccine., Methods: Mothers and fathers of young children at immunization clinics in Shanghai, China, were interviewed about vaccine decision-making and what attributes of a disease were important when making this decision. An inductive thematic analysis explored their beliefs about disease attributes and how these related to vaccination decisions., Results: Among the 34 interviews, severity of the disease-particularly in causing long-term disability-was the most commonly cited factor influencing a parent's decision to get a vaccine for their child. Many parents believed that natural infection was preferable to vaccination, as long as disease was not severe, and many were concerned that imported vaccines were inadequate for Chinese children's physical constitutions. All these beliefs could influence the decision to vaccinate., Conclusions: Many parents do not appear to understand how and why vaccines can support development of a healthy immune system. Because severity emerged as parents' overriding concern when making decisions about vaccines, marketing for a childhood vaccine could focus on the severe condition that a vaccine can protect against.

Background: India has implemented the World Health Organization's revised Causality Assessment Protocol for adverse events following immunization (AEFI). We describe the number and types of serious/severe AEFIs, including deaths., Research Design and Methods: Analysis of causality classification of reported serious/severe AEFIs from 1 January 2012 to 7 January 2016 was done. Classification includes (A) consistent with causal association to immunization; (B) indeterminate; (C) coincidental association; or (D) unclassifiable. We present descriptive statistics across each category., Results: Analysis of causality assessment completed for 1037 reports of serious AEFIs: 499 (48%) were causally associated, 84 (8%) were indeterminate, 323 (31%) were coincidental, and 131 (13%) were unclassifiable. Of the 499 reports in the A category, the events were causally linked to vaccine product for 189 (18%), to immunization error for 135 (13%), and to immunization anxiety for 175 (17%). Among 279 reported deaths, more than half (55%; n = 153) were coincidental events and 37% were unclassifiable., Conclusions: Causality assessment of AEFI cases is an important component of vaccination programs and post-marketing surveillance of vaccines. Field reporting and investigation of AEFIs can be improved for many severe or serious reports, most of which are not causally linked to the vaccination program.

Background: Chinese parents have access to domestic and foreign vaccines for their children. Their vaccine preferences are unclear, especially given recent pharmaceutical quality scandals and widely held beliefs deriving from Traditional Chinese Medicine (TCM). This study characterized parental beliefs about the safety and effectiveness of Chinese and foreign vaccines., Methods: In May 2014, caregivers of young children at public immunization clinics in Shanghai, China, responded to a survey on vaccine perceptions. The two outcomes (differential belief in the effectiveness and safety of foreign vs domestic vaccines) were separately regressed onto demographic predictors in multinomial logistic regression models., Results: Among 618 caregivers, 56% thought the effectiveness of domestic and foreign vaccines were comparable; 33% thought domestic were more effective and 11% foreign. Two-thirds thought foreign and domestic vaccines had similar safety; 11% thought domestic were safer and 21% thought foreign were safer. Compared to college graduates, those with a high school education or less had greater odds of believing domestic vaccines were more effective, and also had greater odds of believing imported vaccines were safer. Greater trust in TCM was not associated with differential beliefs in the effectiveness or safety of domestic vs foreign vaccines., Conclusions: Although there is no evidence that foreign and domestic vaccines differ in either effectiveness or safety, less educated caregivers in China (but not those with greater trust in TCM) appear to believe such differences exist. Further exploration of the causes of these beliefs may be necessary in order to optimize vaccine communications in China., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Delays in vaccination can stymie the development of herd immunity, and a large proportion of children in the U.S. are known not to receive vaccines on time. This study quantifies delays in vaccination, compares vaccination timeliness to the proportion of children vaccinated, and evaluates the impact of combination vaccine use and timely administration of hepatitis B vaccine birth dose on vaccine timeliness among Michigan children., Methods: This retrospective cohort study used data from the Michigan Care Improvement Registry-the state immunization information system-for children born 2006-2010. Children aged 24 months as of December 31, 2012, were included. The proportion of children with timely administration of vaccine doses was calculated, and the mean days of vaccination delay with SD were reported., Results: Among 620,592 Michigan children, 42.2% had received all vaccines, but only 13.2% were vaccinated on time by age 24 months. Children's vaccinations were delayed an average of 59.2 (SD=91.2) days by age 24 months for all recommended vaccine doses. Children who received a timely hepatitis B vaccine birth dose or who received a combination vaccine had less delay in vaccination., Conclusions: Michigan children have high vaccination coverage based on standard measures but few receive these vaccines on time. Promoting use of combination vaccines may improve parental compliance with timely vaccination of children., (Copyright © 2018 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Introduction: Vaccines are vital to reducing childhood mortality, and prevent an estimated 2 to 3 million deaths annually which disproportionately occur in the developing world. Overall vaccine coverage is typically used as a metric to evaluate the adequacy of vaccine program performance, though it does not account for untimely administration, which may unnecessarily prolong children's susceptibility to disease. This study explored a hypothesized positive association between increasing vaccine hesitancy and untimeliness of immunizations administered under the Expanded Program on Immunization (EPI) in Addis Ababa, Ethiopia., Methods: This cross-sectional survey employed a multistage sampling design, randomly selecting one health center within five sub-cities of Addis Ababa. Caregivers of 3 to 12-month-old infants completed a questionnaire on vaccine hesitancy, and their infants' vaccination cards were examined to assess timeliness of received vaccinations., Results: The sample comprised 350 caregivers. Overall, 82.3% of the surveyed children received all recommended vaccines, although only 55.9% of these vaccinations were timely. Few caregivers (3.4%) reported ever hesitating and 3.7% reported ever refusing a vaccine for their child. Vaccine hesitancy significantly increased the odds of untimely vaccination (AOR 1.94, 95% CI: 1.02, 3.71) in the adjusted analysis., Conclusions: This study found high vaccine coverage among a sample of 350 young children in Addis Ababa, though only half received all recommended vaccines on time. High vaccine hesitancy was strongly associated with infants' untimely vaccination, indicating that increased efforts to educate community members and providers about vaccines may have a beneficial impact on vaccine timeliness in Addis Ababa.

The arrival of the COVID-19 vaccine has been accompanied by increased discussion of vaccine hesitancy. However, it is unclear if there are shared patterns between general vaccine hesitancy and COVID-19 vaccine rejection, or if these are two different concepts. This study characterized rejection of a hypothetical COVID-19 vaccine, and compared patterns of association between general vaccine hesitancy and COVID-19 vaccine rejection. The survey was conducted online March 20-22, 2020. Participants answered questions on vaccine hesitancy and responded if they would accept the vaccine given different safety and effectiveness profiles. We assessed differences in COVID-19 rejection and general vaccine hesitancy through logistic regressions. Among 713 participants, 33.0% were vaccine hesitant, and 18.4% would reject a COVID-19 vaccine. Acceptance varied by effectiveness profile: 10.2% would reject a 95% effective COVID-19 vaccine, but 32.4% would reject a 50% effective vaccine. Those vaccine hesitant were significantly more likely to reject COVID-19 vaccination [odds ratio (OR): 5.56, 95% confidence interval (CI): 3.39, 9.11]. In multivariable logistic regression models, there were similar patterns for vaccine hesitancy and COVID-19 vaccine rejection by gender, race/ethnicity, family income, and political affiliation. But the direction of association flipped by urbanicity (P=0.0146, with rural dwellers less likely to be COVID-19 vaccine rejecters but more likely to be vaccine hesitant in general), and age (P=0.0037, with fewer pronounced differences across age for COVID-19 vaccine rejection, but a gradient of stronger vaccine hesitancy in general among younger ages). During the COVID-19 epidemic's early phase, patterns of vaccine hesitancy and COVID-19 vaccine rejection were relatively similar. A significant minority would reject a COVID-19 vaccine, especially one with less-than-ideal effectiveness. Preparations for introducing the COVID-19 vaccine should anticipate substantial hesitation and target concerns, especially among younger adults. [ABSTRACT FROM AUTHOR]

Childhood vaccination in Ghana has historically been high, but the impact of recently introduced vaccines on coverage is unknown. We calculate vaccine coverage of Ghanaian children– contrasting newly introduced vaccines and those long available – and describe associations between sociodemographic indicators and full vaccination. Data from the 2014 Ghana Demographic and Health Survey was used to calculate full vaccination, defined as receipt of one dose bacillus Calmette-Guérin (BCG); two doses of rotavirus vaccine; 3 doses of pentavalent vaccine, oral polio vaccine (OPV), and pneumococcal conjugate vaccine (PCV); and one dose of measles-rubella vaccine and yellow fever vaccine, among children age 12–24 months. Logistic regression with survey procedures was used to estimate odds ratios for socioeconomic factors' association with full vaccination. The sample comprised a total of 1107 children 12–24 months. Full vaccination coverage was 70.8%. Vaccination coverage was higher for vaccines administered at younger ages (e.g., birth dose of BCG was 97.0%) than at older ages (e.g., yellow fever at 9 months was 88.2%). Newly introduced vaccines had lower coverage: at 10 weeks, pentavalent 2 was 95.4%, versus 91.2% for PCV 2 and 88.8% for rotavirus 2. Living outside of Greater Accra, home delivery, younger maternal age, urban residence, and more than one child under five in the home were all associated with decreased odds of full vaccination in the adjusted analysis whereas sex of the child, wealth, religion, and maternal education were not associated with full vaccination status. Ghana has high overall vaccination rates although disparities in full vaccination by sociodemographic status exist. As vaccine recommendations are revised, it will be important to insure equitable access to vaccination for all children regardless of demographic and socioeconomic background. [ABSTRACT FROM AUTHOR]

Background: We characterize the risk factors for delayed polio dose 1, diphtheria-tetanus-pertussis (DTP) dose 1, pentavalent dose 1, and measles dose 1 in Ethiopian infants. We also examine the interaction between institutional delivery and demographic factors on the birth doses of the BCG and polio vaccines to better understand factors influencing vaccination. Methods: Using the 2011 Ethiopia Demographic and Health Survey, we calculated the distribution of the study population across different demographic and vaccination characteristics. We computed acceleration factors using a multivariable accelerated failure time model with a Weibull distribution to account for left and right censoring. For the birth doses, we further specified an interaction term between institutional delivery and every other a priori specified independent variable to test whether institutional delivery modifies sociodemographic disparities in vaccination timeliness. Results: Low wealth status, home delivery, and ethnicity are risk factors for delayed vaccination of polio 1, DPT 1, pentavalent 1, and measles 1. Religion is a risk factor for measles 1 vaccination delay and rural residence are risk factors for delayed DPT1 and polio 1 doses. For birth doses of polio and BCG, institutional delivery attenuated many sociodemographic disparities in vaccination delay, except for urbanicity, which showed rural dwellers with more delay than urban dwellers with an institutional vs home birth. Conclusions: Less delayed vaccination among children with institutional deliveries highlights the importance of perinatal care and the potential for promoting healthy behaviors to parents. Persistent disparities between urban and rural residents, even among those with institutional births, can be targeted for future interventions. Timely vaccination is key to prevention of unnecessary childhood mortality. [ABSTRACT FROM AUTHOR]

Background: Severe Acute Respiratory Infection (SARI) causes substantial mortality and morbidity worldwide. The country of Georgia conducts sentinel surveillance to monitor SARI activity and changes in its infectious etiology. This study characterizes the epidemiology of SARI in Georgia over the 2015/16 and 2016/17 influenza seasons, compares clinical presentations by etiology, and estimates influenza vaccine effectiveness using a test-negative design. Methods: SARI cases were selected through alternate day systematic sampling between September 2015 and March 2017 at five sentinel surveillance inpatient sites. Nasopharyngeal swabs were tested for respiratory viruses and Mycoplasma pneumoniae using a multiplex diagnostic system. We present SARI case frequencies by demographic characteristics, co-morbidities, and clinical presentation, and used logistic regression to estimate influenza A vaccine effectiveness. Results: 1,624 patients with SARI were identified. More cases occurred in February (28.7%; 466/1624) than other months. Influenza was the dominant pathogen in December-February, respiratory syncytial virus in March-May, and rhinovirus in June-November. Serious clinical symptoms including breathing difficulties, ICU hospitalization, and artificial ventilation were common among influenza A and human metapneumovirus cases. For influenza A/H3, a protective association between vaccination and disease status was observed when cases with unknown vaccination status were combined with those who were unvaccinated (OR: 0.53, 95% CI: 0.30, 0.97). Conclusions: Multi-pathogen diagnostic testing through Georgia’s sentinel surveillance provides useful information on etiology, seasonality, and demographic associations. Influenza A and B were associated with more severe outcomes, although the majority of the population studied was unvaccinated. Findings from sentinel surveillance can assist in prevention planning. [ABSTRACT FROM AUTHOR]

Background Timely administration of recommended vaccines requires children to have multiple vaccines co-administered in the first year of life. The objectives of this study were to estimate the proportion of timely vaccinations and the proportion of co-administered vaccines, and to assess the relationship between vaccine co-administration and vaccine timeliness in Kenyan children. Methods Using the 2014 Kenyan Demographic and Health Survey (DHS), we calculated the proportion of children who received co-administered and timely vaccine doses. Co-administration was defined as doses administered on the same day with dates recorded on vaccination cards. Vaccines were considered timely if given within four days before to four weeks after the recommended interval for administration. Results 10,385 children aged 1–4 years in the Kenyan 2014 DHS dataset had vaccination cards which comprised the study sample. Analysis revealed wide a range for receipt of timely doses, from 90.2% for OPV0 to 56.0% for Measles. Co-administration of the 6-week dose was associated with 2.81 times higher odds of a timely Penta dose 1 (95% CI: 2.28, 3.46) and birth-dose co-administration was associated with a substantial increase in timely BCG vaccination: AOR 7.43 (95% CI: 6.31, 8.75). Conclusions Though vaccine coverage in Kenya was high, timely vaccination was markedly low, with resultant implications for population immunity and potential spread of communicable diseases in unvaccinated infants. Co-administration of vaccines, place of residence, wealth index, and child age were consistently related to the odds of timely vaccine receipt. These relationships reinforce the importance of dedicating resources to programs that educate low socio-economic groups about the importance of vaccine co-administration. [ABSTRACT FROM AUTHOR]

Background: Afghanistan’s public health system was neglected during decades of military and civil conflict, and trends in infectious disease occurrence remain poorly characterized. This study examines cyclical and long-term trends of six vaccine-preventable diseases: pneumonia, diarrhea, meningitis, typhoid, measles, and acute viral hepatitis. Methods: Using weekly data collected between 2009 and 2015 through Afghanistan’s Disease Early Warning System, we calculated monthly case counts, and fit a Poisson regression with a Fourier transformation for seasonal cycles and dummy variables for year. Results: We found the greatest incidence of diarrhea and typhoid in the summer, pneumonia in the winter, and measles in the late spring. Meningitis and acute viral hepatitis did not demonstrate substantial seasonality. Rates of pneumonia and diarrhea were constant across years whereas rates of meningitis, typhoid, and acute viral hepatitis decreased. Measles incidence increased in 2015. Conclusions: Communicable disease reporting systems can guide public health operations–such as the implementation of new vaccines, and permit evaluation of health interventions. For example, measles supplementary immunization activities in Afghanistan have not slowed long-term transmission of the disease, but decreases in typhoid fever and acute viral hepatitis are probably tied to improvements in sanitation in the country. [ABSTRACT FROM AUTHOR]

Background: Haemophilus influenzae type b (Hib) vaccine and pneumococcal conjugate vaccine (PCV) are relatively expensive, newly introduced vaccines in China. This study evaluates the impact of residency and urbanicity on Hib vaccine and PCV coverage for children aged 2 to 7 years living in Shanghai, China, in August 2012. Methods: In this exploratory cohort study, a sample of children aged 2 to 7 years, all of whom were eligible to have received the complete series of Hib vaccine and PCV, was obtained from the Shanghai Immunization Program Information System. Three measures of vaccination coverage for Hib vaccine and PCV were examined: dose 1 coverage, series completion, and timeliness of dose 1 vaccination. Multivariable binomial regression was used to estimate the difference in vaccination coverage between locals and the floating population. Results: Dose 1 coverage was 50.9% for Hib vaccine and 11.4% for PCV for the 28,141 abstracted pediatric records. For both vaccines, dose 1 coverage was higher in locals than in the floating population. The disparity in coverage between locals and the floating population was greater in suburban areas than urban areas. Of all children who received dose 1, 79.7% completed the Hib vaccine series, and 91.3% completed the PCV series. Timely dose 1 coverage was 8.2% for Hib vaccine and 0.5% for PCV. Conclusion: Low vaccination coverage and extremely low levels of timely dose 1 vaccination indicate that current vaccination efforts are inadequate to reduce the burden of Hib and pneumococcal disease among Chinese children, especially infants. Government funding of the Hib vaccine and PCV through the Expanded Program on Immunization would increase uptake and could also ensure that improvement in the timeliness of administration and series completion is targeted for all demographic groups. [ABSTRACT FROM AUTHOR]

Controlling the spread of SARS-CoV-2 will require high vaccination coverage, but acceptance of the vaccine could be impacted by perceptions of vaccine safety and effectiveness. The aim of this study was to characterize how vaccine safety and effectiveness impact acceptance of a vaccine, and whether this impact varied over time or across socioeconomic and demographic groups. Repeated cross-sectional surveys of an opt-in internet sample were conducted in 2020 in the US, mainland China, Taiwan, Malaysia, Indonesia, and India. Individuals were randomized into receiving information about a hypothetical COVID-19 vaccine with different safety and effectiveness profiles (risk of fever 5% vs. 20% and vaccine effectiveness 50% vs. 95%). We examined the effect of the vaccine profile on vaccine acceptance in a logistic regression model, and included interaction terms between vaccine profile and socioeconomic/demographic variables to examine the differences in sensitivity to the vaccine profile. In total, 12,915 participants were enrolled in the six-country study, including the US (4054), China (2797), Taiwan (1278), Malaysia (1497), Indonesia (1527), and India (1762). Across time and countries, respondents had stronger preferences for a safer and more effective vaccine. For example, in the US in November 2020, acceptance was 3.10 times higher for a 95% effective vaccine with a 5% risk of fever, vs a vaccine 50% effective, with a 20% risk of fever (95% CI: 2.07, 4.63). Across all countries, there was an increase in the effect of the vaccine profile over time (p < 0.0001), with stronger preferences for a more effective and safer vaccine in November 2020 compared to August 2020. Sensitivity to the vaccine profile was also stronger in August compared to November 2020, in younger age groups, among those with lower income; and in those that are vaccine hesitant. Uptake of COVID-19 vaccines could vary in a country based upon effectiveness and availability. Effective communication tools will need to be developed for certain sensitive groups, including young adults, those with lower income, and those more vaccine hesitant. [ABSTRACT FROM AUTHOR]

Low- and middle-income countries receive limited guidance from external entities about how to introduce vaccines. This is especially true for the Hepatitis E (HepE) vaccine, which is currently only commercially available in China. The aims of this qualitative study are to identify which attributes of the HepE disease and vaccine are considered important, and to compare desired promotion methods between different stakeholders. Stakeholders included experts (Centers for Disease Control and Prevention staff, health care providers, and researchers), and nonexperts included members of high-risk populations, HepE cases, and vaccinees. Participants' thoughts were coded and broadly summarized. We contacted 63 persons—35 experts and 28 nonexperts. Safety and effectiveness (but not price) of the vaccine, along with severity of disease and transmission route of infection, were all listed as important attributes. Emphasizing the importance of sharing stories from cases, relying on personal experiences, staying away from statistical explanations, and using the government as a source of promotion were other points repeatedly raised by the participants. Qualitative interviews with experts and nonexperts has revealed that focusing on attributes of disease severity and susceptibility to infection, as well as vaccine safety and effectiveness within stories of cases, are preferred ways to promote the vaccine. [ABSTRACT FROM AUTHOR]

Vaccine hesitancy is a continuum of behaviors ranging from delay in receipt to vaccination refusal. Prior studies have typically focused on high-income countries, where vaccine hesitancy is particularly prevalent in more affluent groups, but the relationship between socioeconomic status and vaccine hesitancy in Low- and Middle-Income Countries (LMICs) is less clear. The aim of this study was to describe vaccine hesitancy in five LMICs. Mothers of children in Sirajganj, Bangladesh (n = 60), Shanghai, China (n = 788), Addis Ababa, Ethiopia (n = 341), Guatemala City and Quetzaltenango, Guatemala (n = 767), and Chandigarh, India (n = 309), completed a survey between 2016 and 2018 using the WHO's 10-item Vaccine Hesitancy Scale. The scores of different constructs were compared across countries and by the mother's education level using linear regression models with generalized estimating equations. Compared to mothers in China, mothers in Bangladesh perceived less vaccination benefit (β: 0.56, P = 0.0001), however, mothers in Ethiopia (β: −0.54, P < 0.0001) and Guatemala (β: −0.74, P = 0.0004) perceived greater benefit. Education level was not significantly linked with vaccine hesitancy. Local circumstances are important to consider when developing programs to promote vaccines. We did not find consistent associations between education and vaccine hesitancy. More research is needed to understand socio-cultural influences on vaccine decision-making. [ABSTRACT FROM AUTHOR]

Internationally, vaccine pricing is relatively opaque, although many low- or lower-middle-income countries belong to international consortiums that jointly procure vaccines. China procures vaccines domestically, and vaccines that require payment from the public ("category 2 vaccines"), have undergone several regulatory changes over the past 15 years. This study aims to describe the vaccine procurement method changes in China since 2005 and to analyze how the procurement method impacted vaccine price. This review of vaccine procurement reforms found that a shift to provincial-level Group Purchasing Organizations after 2016 was accompanied by an increase in most prices. There was more variability in vaccine prices across provinces for vaccines with only one supplier, and these vaccines have a higher price than what is found in United Nations Children's Fund (UNICEF)-supported countries. China's current procurement system for non-mandatory vaccines leaves these vaccines costing several-fold more than in other countries, and in particular those supported by Gavi, the Vaccine Alliance. Exploring a variety of methods to reduce vaccine purchase prices will not only directly benefit the general population, but also the government, as they aim to implement more programs to benefit public health in a cost-effective manner. [ABSTRACT FROM AUTHOR]