Birth outcomes for Australian mother-infant pairs who received an influenza vaccine during pregnancy, 2012–2014: The FluMum study

IntroductionIn Australia, influenza vaccination is recommended for all women who will be pregnant during the influenza season. Vaccine safety and effectiveness are key concerns and influencers of uptake for both vaccine providers and families. We assessed the safety of receiving an influenza vaccination during any trimester of pregnancy with respect to preterm births and infant birthweight.MethodsWe conducted a nested retrospective cohort study of ‘FluMum’ participants (2012–2014). Our primary exposure of interest was influenza vaccination during pregnancy. The primary outcomes of interest were infant birthweight and weeks’ gestation at birth for live singleton infants. Analyses included comparisons of these birth outcomes by vaccination status and trimester of pregnancy an influenza vaccine was given. We calculated means, proportions, and relative risks and performed multivariable logistic regression for potential confounding factors.ResultsIn the 7126 mother-infant pairs enrolled in this study, mean maternal age at infant birth was 31.7 years. Influenza vaccine uptake in pregnancy was 34%. Most mothers with a known date of vaccination received a vaccine in the second trimester (51%). Those mothers with a co-morbidity or risk factor were 13% more likely to have influenza vaccine during pregnancy compared to other mothers (RR 1.13, 95% CI 1.04–1.24, p = 0.007). Mean weeks’ gestation at birth was 38.7 for the vaccinated and 38.8 for the unvaccinated group (p = 0.051). Infants in the vaccinated group weighed 15 g less in birthweight compared to the unvaccinated infants (95% CI −12.8 to 42.2, p = 0.29).ConclusionResults arising from this large Australian cohort study are reassuring with respect to two critical safety outcomes; preterm births and low infant birthweights. Studies examining a broader range of birth outcomes following influenza vaccination during pregnancy are required, particularly now that maternal vaccination in pregnancy has expanded to include pertussis as well as influenza.     

What is ‘confidence’ and what could affect it?: A qualitative study of mothers who are hesitant about vaccines

BackgroundPublic confidence in immunization is critical to maintaining high vaccine-coverage rates needed to protect individuals and communities from vaccine-preventable diseases. Recent attention has been placed on factors influencing confidence in vaccination in the US and globally, but comprehensive understanding of what drives or hinders confidence in childhood vaccination is yet to be reached. As such, assessing parents' confidence in childhood vaccination and the ways in which educational materials affect confidence is needed.ObjectiveWe sought to (1) learn how mothers who are hesitant about vaccination characterize confidence in health-related products for young children, including the recommended vaccines; (2) gain insights on what influences vaccine confidence beliefs; and (3) assess whether short, education materials affect parental confidence in childhood vaccinations.MethodsEight moderator-lead focus groups (n = 61), stratified by socioeconomic status, were undertaken with mothers of children 5 years of age of less who are hesitant about vaccines. Four of the groups were held in the Philadelphia, PA area and four were held in the San Francisco/Oakland, CA area. Three educational material pairs, each consisting of a 2–3 min video and an infographic poster about an immunization-related topic, were reviewed and assessed for influence on confidence.ResultsQualitative data analysis was used to identify overarching themes across the focus groups. Themes, insights, and illustrative quotes were identified and provided for each of the major discussion areas: primary health concerns for young children; confidence beliefs and perceptions, including for recommended vaccines; facilitators and barriers to confidence; and reactions to the educational materials.ConclusionsResults provide helpful insights into how mothers who are hesitant about vaccines perceive confidence in childhood vaccines and health-related products, suggestions for how to improve confidence, and support for the value and use of short videos as part of vaccination education efforts. Findings can aid those developing vaccination education materials and resources designed to foster vaccine confidence.     

Influence of information sources on vaccine hesitancy and practices

IntroductionMany factors influence vaccination practices and attitudes. This study aimed to identify vaccine information sources used by parents of children aged 1–15 years to get a better understanding of the relation between vaccine information sources, practices for two vaccines (MMR, HBV), vaccine acceptance, and vaccine hesitancy.MethodsA total of 3938 parents, drawn by random sampling, were interviewed by telephone as part of the “2016 health barometer” survey. Vaccine information sources were described and analyzed according to socio-demographic variables. Multivariate logistic regression models were then built to explain vaccine information sources usage, vaccination practices and attitudes.ResultsHealthcare professionals (HCP), the Internet, and relatives were the three main vaccine information sources. Vaccination practices and acceptance were better when parents were getting information from HCPs compared with parents getting information from the Internet or relatives. Besides, getting information from the three different types of sources was associated with the highest rate of vaccine hesitancy: 70.9% (OR = 4.6; P < 0.0001) versus 34.6% among parents getting information from HCPs only.ConclusionThose results suggest an interest in providing quality information about vaccination on the Internet. The primary role of HCPs in vaccination decision is once again demonstrated.     

The determinants of vaccine hesitancy in China: A cross-sectional study following the Changchun Changsheng vaccine incident

IntroductionVaccine hesitancy is cited as one of the top threats to global health. The Changchun Changsheng Biotechnology Company was found to have violated good manufacturing practices in July 2018, leading to widespread distribution of sub-potent vaccines in China. We estimated the prevalence and determinants of vaccine hesitancy following the Changchun Changsheng vaccine incident (CCVI).MethodsWe conducted a cross-sectional survey in China in January 2019, and 2,124 caregivers of children < 6 years old completed self-administered questionnaires. Multinomial logistic regression was used to assess the determinants of vaccine hesitancy; the potential determinants included demographics, socioeconomic status, vaccine confidence, and knowledge of the CCVI. Adjusted Odds Ratios (AORs) and 95% confidence intervals (CI) are reported.ResultsAround 89% of caregivers had heard of the CCVI. Although 83% and 88% of caregivers agreed that vaccines are safe and effective, respectively, 60% expressed some hesitancy about vaccination. Of those hesitant, 26% vaccinated their children at times with doubts, 31% delayed vaccination and 3% refused specific vaccines. Multinomial regression analysis showed that confidence in vaccine safety was associated with a reduced odds of doubts on vaccination (AOR = 0.64; 95%CI = 0.44–0.94), whereas caregivers who had heard of the CCVI had a significantly higher odds of doubts on vaccination (AOR = 1.61; 95%CI = 1.05–2.45). Confidence in the vaccine delivery system and government were associated with a lower odds of vaccine hesitancy. Caregivers with higher education and Buddhism or other religions were significantly more hesitant to vaccinate their children.ConclusionVaccine hesitancy was prevalent following the CCVI. Over half the caregivers either accepted childhood vaccination with doubts or delayed vaccines; only a small number were active refusers. Our findings highlight the importance of addressing vaccine hesitancy, especially following vaccine incidents. Tailored communications are needed to reduce vaccine hesitancy, especially among the highly educated and Buddhist caregivers.     

Brief education to promote maternal influenza vaccine uptake: A randomized controlled trial

BackgroundAlthough pregnant women are the highest priority group for seasonal influenza vaccination, maternal influenza vaccination rates remain suboptimal. The purpose of this study was to evaluate the effect of a brief education intervention on maternal influenza vaccine uptake.MethodsDuring the 2013–14 and 2014–15 influenza seasons, we recruited 321 pregnant women from the antenatal clinics of 4 out of 8 public hospitals in Hong Kong with obstetric services. Hospitals were geographically dispersed and provided services to pregnant women with variable socioeconomic backgrounds. Participants were randomized to receive either standard antenatal care or brief one-to-one education. Participants received telephone follow-up at 2 weeks postpartum. The primary study outcome was self-reported receipt of influenza vaccination during pregnancy. The secondary outcomes were the proportion of participants who initiated discussion about influenza vaccination with a health care professional and the proportion of participants who attempted to get vaccinated.ResultsCompared with participants who received standard care, the vaccination rate was higher among participants who received brief education (21.1% vs. 10%; p = 0.006). More participants in the education group initiated discussion about influenza vaccination with their HCP (19.9% vs. 13.1%; p = 0.10), but the difference was not statistically significant. Of participants who did not receive the influenza vaccine (n = 271), 45 attempted to get vaccinated. A significantly higher proportion of participants who attempted to get vaccinated were in the intervention group (82.2% vs. 17.8%; p < 0.001). If participants who had attempted vaccination had received the vaccine, vaccination rates would have been substantially higher (44.1% vs. 15%; p < 0.001). Twenty-six participants were advised against influenza vaccination by a healthcare professional, including general practitioners, obstetricians, and nurses.ConclusionAlthough brief education was effective in improving vaccination uptake among pregnant women, overall vaccination rates remain suboptimal. Multicomponent approaches, including positive vaccination recommendations by healthcare professionals, are needed to promote maternal influenza vaccination.Clinical Trial Registration: www.clinicaltrials.gov (NCT01772901).     

Intention to accept pertussis vaccine among pregnant women in Karachi,Pakistan

BackgroundMaternal immunization against pertussis is a potential strategy to protect young infants from severe disease. We assessed factors associated with intention to accept pertussis vaccination among pregnant women in Karachi, Pakistan.MethodsWe conducted a cross-sectional survey between May and August 2013 in pregnant women who visited healthcare centers in urban slums of Karachi city. Women completed a survey examining socio-demographic factors, vaccination history, knowledge on pertussis disease, perception of vaccine recommendation sources, and potential influences on vaccine decision-making.ResultsOf the 283 participants, 259 (92%) provided their intention to either accept or decline pertussis vaccination. Eighty-three percent women were willing to accept the pertussis vaccine if offered during pregnancy. About half (53%) of the participants had ever heard of pertussis disease. Perceptions of pertussis vaccine efficacy, safety, and disease susceptibility were strongly associated with intention to accept pertussis vaccine (p < 0.01). Healthcare providers, Ministry of Health, and mass media were considered as highly reliable sources of vaccine recommendation and associated with intention to accept antenatal pertussis vaccination (p < 0.001). Healthcare provider recommendation was a common reason cited by respondents for pregnant women to accept antenatal pertussis vaccination (p = 0.0005). However, opinion of primary decision-makers in the family (husbands and in-laws) was a crucial reason cited by respondents for pregnant women to reject pertussis vaccination in pregnancy (p = 0.003).ConclusionAntenatal pertussis vaccination initiatives in South Asia should strongly consider inclusion of family members, healthcare providers, national health ministries, and mass media to help implement new vaccination programs.     

Identification of determinants associated with uptake of the first dose of the human papillomavirus vaccine in Denmark

BackgroundThe human papillomavirus vaccine (HPV vaccine) was introduced into the Danish Childhood Vaccination Programme in 2009. Following a national debate questioning the safety of the vaccine, the coverage decreased from an uptake of >90% for the first dose of the HPV vaccine to an uptake of 52% in girls born in 2003. The aim of this study was to identify changes in determinants for HPV vaccine hesitancy in the period when the debate spiraled and to identify determinants for specific hesitancy towards the HPV vaccine among girls who received the second dose of the measles, mumps and rubella vaccine.MethodsWe included girls born in the period 1999–2003 who were residing in Denmark between their 12th and 13th birthday (n = 161,528). Data from the Danish Vaccination Register were linked with demographic data from the Danish Civil Registration System. We used multiple logistic regression models to identify associations between determinants and the uptake of the first dose of the HPV vaccine (HPV1).ResultsFor girls born in 1999–2000, low uptake was seen in children of increasing birth order, young or old age of mother, non-Danish origin, low uptake of other childhood vaccines, and in girls living with one parent. For girls born in 2001–2003, most of these determinants of low uptake became less significant. Birth order and origin showed different tendencies when comparing birth cohorts 1999–2000 with birth cohorts 2001–2003.ConclusionsWe found demographic disparities in the uptake of HPV1 that were generally in line with existing literature. More importantly, the results indicate that determinants for hesitancy towards the HPV vaccines changed during a period of intense public debate regarding the safety of the HPV vaccine. This may indicate that the public concerns over safety disproportionally affect those who trusted vaccines prior to the debate.     

Vaccine hesitancy among parents of adolescents and its association with vaccine uptake

BackgroundAddressing parental vaccine hesitancy may increase adolescent vaccination acceptance. However, no validated measure exists to identify parents hesitant toward adolescent vaccines.ObjectiveTo determine if a modified version of the Parent Attitudes about Childhood Vaccines (PACV) survey, a previously validated tool to identify parental hesitancy toward vaccines in infants, predicts adolescent vaccine uptake at office visits.MethodsWe modified the PACV for use in the adolescent setting and distributed it to a convenience sample of parents of adolescents aged 11 to 17 presenting for care at a diverse group of six pediatric practices in Oklahoma and South Carolina. We determined the vaccination status of the parents’ adolescents for 3 vaccines (Tetanus–diphtheria–acellular pertussis [Tdap], meningococcal conjugate [MCV4], and human papillomavirus [HPV] vaccines). We used Fisher's exact tests to compare vaccination status with each survey item and with an overall general hesitancy scale that we constructed.ResultsWe analyzed 363 surveys. At the time of the visit, vaccination coverage was 84% for Tdap, 73% for MCV, and 45% for any dose of HPV. Thirty-nine percent of parents expressed concern about vaccine efficacy and 41% expressed concern about side effects. Forty-five percent of parents disagreed with the statement that “teens can get all of the vaccines that are due at a single visit.” Two individual items were associated with not receiving a dose of HPV vaccine that was due. The overall modified PACV score failed to predict adolescent vaccine uptake at an office visit.ConclusionSeveral individual items were associated with vaccine uptake. The cumulative modified PACV, a general measure of vaccine hesitancy, was not associated with vaccination status despite illuminating parental hesitancy. We need to better understand vaccine-specific concerns for the adolescent population.     

Parental vaccine hesitancy and acceptance of seasonal influenza vaccine in the pediatric emergency department

BackgroundProviding influenza vaccine to patients in the pediatric emergency department (PED) is one strategy to increase childhood influenza vaccine uptake. The Parent Attitudes about Childhood Vaccines (PACV) survey is a new tool to identify vaccine-hesitant parents that may facilitate influenza vaccine uptake in the PED.ObjectiveTo assess the feasibility of administering the PACV modified for influenza vaccination in the PED setting and to determine whether parental PACV scores are associated with patient receipt of influenza vaccine in the PED.MethodsWe conducted a cross-sectional study in the PED of a tertiary pediatric hospital in Seattle, WA during the 2013–2014 influenza season. English-speaking parents of children aged 6 months to 7 years who were afebrile, medically stable to be discharged home from the PED, and had not already received an influenza vaccine this season were administered a modified version of the PACV. PACV scores (0–100, higher score = higher hesitancy) were dichotomized (<50 and ≥50) consistent with previous validation studies. Feasibility was assessed by determining time to complete the PACV. Our primary outcome was influenza vaccine refusal in the PED. We used multivariable logistic regression to estimate unadjusted and adjusted odds ratios for association between vaccine refusal and dichotomized PACV scores.Results152 parent participants were included in the analysis. The median time for administering the PACV was 7 min. The median PACV score was 28, with 74% scoring <50. Parents who scored ≥50 on the PACV had increased odds of refusing the influenza vaccine compared to parents who scored <50 (adjusted OR [95% CI]: 6.58 [2.03–21.38]).ConclusionAdministration of the PACV in the PED is feasible, and higher PACV scores in this setting are associated with increased influenza vaccine refusal.     

Changes in childhood immunization decisions in the United States: Results from 2012 & 2014 National Parental Surveys

ObjectiveUnderstanding the current status of parents’ vaccine decision making is crucial to inform public policy. We sought to assess changes in vaccine decisions among parents of young children.MethodsWe conducted a web-based national poll of parents of children <7 years in 2012 and 2014. Participants reported vaccine decisions for their youngest child. We calculated survey-weighted population estimates of overall immunizations decisions, and delay/refusal rates for specific vaccines.ResultsIn 2012, 89.2% (95% CI, 87.3–90.8%) reported accepting or planning to accept all recommended non-influenza childhood vaccines, 5.5% (4.5–6.6%) reported intentionally delaying one or more, and 5.4% (4.1–6.9%) reported refusing one or more vaccines. In 2014, the acceptance, delay, and refusal rates were 90.8% (89.3–92.1%), 5.6% (4.6–6.9%), and 3.6% (2.8–4.5%), respectively. Between 2012 and 2014, intentional vaccine refusal decreased slightly among parents of older children (2–6 years) but not younger children (0–1 years). The proportion of parents working to catch up on all vaccines increased while those refusing some but not all vaccines decreased. The South experienced a significant increase in estimated acceptance (90.1–94.1%) and a significant decrease in intentional ongoing refusal (5.0–2.1%). Vaccine delay increased in the Northeast (3.2–8.8%).ConclusionsNationally, acceptance and ongoing intentional delay of recommended non-influenza childhood vaccines were stable. These findings suggest that more effort is warranted to counter persistent vaccine hesitancy, particularly at the local level. Longitudinal monitoring of immunization attitudes is also warranted to evaluate temporal shifts over time and geographically.     

Effect of introduction of pentavalent vaccine as replacement for Diphtheria–Tetanus–Pertussis and Hepatitis B vaccines on vaccination uptake in a health facility in Nigeria

BackgroundThe introduction of a new vaccine into an immunization programme may affect the immunization system negatively or positively. The aim of this study is to determine the effect of the introduction of the pentavalent vaccine as replacement for DTP and Hepatitis B vaccines on timeliness, completion of the schedule and dropout rates among children attending a health facility.MethodologyThis was a retrospective cohort study which involved extracting immunization records of children attending the Institute of Child Health Child Welfare Clinic between June 2011 and May 2013. Pentavalent vaccine was introduced as a replacement for DTP and Hepatitis B vaccines in June 2012. The uptake, timeliness and dropout rates of different vaccines in the immunization schedule were determined for children who commenced immunization in the pre, peri and post introduction phases.ResultsA total of 1110 children were studied – 190, 410 and 510 who commenced vaccination in the pre, peri and post introduction phases of the pentavalent vaccine respectively. Uptake was significantly higher for all vaccines in the post introduction phase compared to pre and peri introduction phases (p < 0.001). Completion of the immunization schedule by 60.2% of the children who commenced vaccination in the post introduction phase was higher than the 31.6% and 41.7% for the pre and peri introduction phases respectively (p < 0.001). Significantly more visits were required to complete the schedule in the peri introduction phase compared to the pre and post introduction phases p < 0.001. Delay in receipt of the three doses of DTP/PENTA was significantly longer in the peri introduction phase compared to pre and post introduction phases.ConclusionThe introduction of pentavalent vaccine significantly improved uptake of vaccines and completion of the schedule but resulted in prolonged delay in receipt of vaccines during the introduction period.     

Vaccine hesitancy among parents in a multi-ethnic country,Malaysia

BackgroundVaccine hesitancy is a threat in combating vaccine-preventable diseases. It has been studied extensively in the Western countries but not so among Asian countries.ObjectivesTo assess the test-retest reliability of the Parent Attitudes about Childhood Vaccines (PACV) questionnaire in Malay language; to determine the prevalence of vaccine hesitancy among parents and its associations with parents' socio-demographic characteristics.MethodsForward and backward translation of PACV in Malay language was carried out. The reliability of the Malay-PACV questionnaire was tested among parents with children. The same questionnaire was used to study vaccine hesitancy among parents in a tertiary hospital in Kuala Lumpur. Information pertaining to socio-demographic characteristics, sources of information regarding vaccination and vaccine hesitancy were collected. Associations between vaccine hesitancy with socio-demographic factors were tested using Multivariable Logistic Regression.ResultsThe Spearman correlation coefficient and Cronbach alpha for total PACV was 0.79 (p < 0.001) and 0.79 respectively. The intra-class correlation coefficients of the subscales ranged from 0.54 to 0.90 demonstrating fair to excellent reliability. A total of 63 (11.6%) parents were noted to be vaccine hesitant. In the univariate analyses, vaccine hesitancy was associated with unemployed parents, parents who were younger, had fewer children and non-Muslim. In the multivariate model, pregnant mothers expecting their first child were four times more likely to be vaccine hesitant compared to those who already had one or more children (aOR: 3.91, 95% CI: 1.74–8.79) and unemployed parents were also more likely to be vaccine hesitant (aOR: 1.97, 95% CI: 1.08–3.59). The internet (65.6%) was the main source of information on vaccination followed by brochures (56.9%).ConclusionThe Malay-PACV questionnaire is reliable to be used. The prevalence of vaccine hesitancy among the multi-ethnic Malaysians was comparable with other populations. Pregnant mothers expecting their first child and unemployed parents were found to be more vaccine hesitant.     

Comparative analysis of the Parent Attitudes about Childhood Vaccines (PACV) short scale and the five categories of vaccine acceptance identified by Gust et al.

BackgroundThere is a need to develop a standardized tool to aid in identifying, measuring and classifying the unique needs of vaccine-hesitant parents (VHPs). This will also assist in designing tailored interventions to address these needs. The Parental Attitude about Childhood Vaccines (PACV) short scale developed by Opel et al., and the Gust et al. vaccine acceptance categories have been acknowledged as potentially useful tools to measure parental vaccine hesitancy. The PACV short scale requires further validation. In our study, we evaluated how the Gust et al. vaccine acceptance categories correspond with the PACV short scale.MethodsAs part of a larger study on vaccine attitudes, using the PACV short scale and Gust et al. vaccine acceptance categories, we assessed the correlation between the two measures using Spearman correlation coefficient, and the association between the two measures using the Cochran-Mantel-Haentszel test of association. We used logistic regression modelling to compare the association between a child’s up-to-date immunization status and (a) PACV short scale and (b) Gust et al. vaccine acceptance categories.ResultsThe PACV short scale and Gust et al. vaccine acceptance categories were positively correlated (r = 0.6, df = 198, p < 0.05), and the Cochran-Mantel-Haentszel test of association yielded a statistically significant association (p < 0.05). The two scales similarly predicted children’s up-to-date immunization status for all recommended childhood vaccines.ConclusionThe ability of the PACV short scale to identify and classify parental vaccine hesitancy is similar to classification using Gust et al. vaccine acceptance categories, and both measure linear entities. The PACV short scale is recommended for screening parents at their first pediatric visit because it is easier to administer. A clearer understanding of how to classify parental vaccine hesitancy can be used to design tailored interventions based on these classifications, to address their specific needs.     

Real-world uptake of COVID-19 vaccination among individuals expressing vaccine hesitancy: A registry-linkage study

Introduction Uptake of COVID-19 vaccination remains suboptimal in the United States and other settings. Though early reports indicated that a strong majority of people were interested in receiving the COVID-19 vaccine, the association between vaccine intention and uptake is not yet fully understood. Our objective was to describe predictors of vaccine uptake, and estimate the sensitivity, specificity, and predictive values of self-reported COVID-19 vaccine status compared to a comprehensive statewide COVID-19 vaccine registry.Methods A cohort of California residents that received a molecular test for SARS-CoV-2 infection during 24 February-5 December 2021 were enrolled in a telephone-administered survey. Survey participants were matched with records in a statewide immunization registry. Cox proportional hazards model were used to compare time to vaccination among those unvaccinated at survey enrollment by self-reported COVID-19 vaccination intention.ResultsAmong 864 participants who were unvaccinated at the time of interview, 272 (31%) had documentation of receipt of COVID-19 vaccination at a later date; including 194/423 (45.9%) who had initially reported being willing to receive vaccination, 41/185 (22.2%) who reported being unsure about vaccination, and 37/278 (13.3%) who reported unwillingness to receive vaccination. Adjusted hazard ratios (aHRs) for registry-confirmed COVID-19 vaccination were 0.49 (95% confidence interval: 0.32–0.76) and 0.21 (0.12–0.36) for participants expressing uncertainty and unwillingness to receive vaccination, respectively, as compared with participants who reported being willing to receive vaccination. Time to vaccination was shorter among participants from higher-income households (aHR = 3.30 [2.02–5.39]) and who reported co-morbidities or immunocompromising conditions (aHR = 1.54 [1.01–2.36]). Sensitivity of self-reported COVID-19 vaccination status was 82% (80–85%) overall, and 98% (97–99%) among those referencing vaccination records; specificity was 87% (86–89%).ConclusionWillingness to receive COVID-19 vaccination was an imperfect predictor of real-world vaccine uptake. Improved messaging about COVID-19 vaccination regardless of previous SARS-CoV-2 infection status may help improve uptake.     

Vaccine hesitancy towards childhood immunisation amongst urban pregnant mothers in Malaysia

BackgroundVaccine hesitancy is a complex behaviour which involves various degrees of indecision about specific vaccines or vaccination uptake. Access to antenatal care had been associated with positive vaccine behavior.ObjectiveTo determine the prevalence of vaccine hesitancy towards childhood immunisation amongst urban pregnant mothers and the associated socio-demographic factors.MethodsA cross-sectional study was conducted among 1081 women who received antenatal care at a teaching hospital in Kuala Lumpur. Vaccine hesitancy was assessed using the Parent Attitudes about Childhood Vaccines (PACV) Survey in both English and validated Malay versions. The sociodemographic data of the mothers and their partners, source of vaccine information and reasons for hesitancy were analysed.ResultsEighty-six (8.0%) pregnant mothers were vaccine hesitant. Ethnicity, religion, number of children, educational level and employment status were significantly associated with vaccine hesitancy. Multivariable analysis showed that a low level of education was the most significant risk factor (p < 0.001), followed by religion (p = 0.03). Health professionals was the main source of information about vaccine. The non-vaccine hesitant women were more likely to seek information from health professionals, and health books and magazine. Fear of adverse side effects of vaccines was the predominant concern for all participants (58%) whilst fear of vaccination pain, preference for alternative medicine and lack of trust in the pharmaceutical industry were significant reasons given by the vaccine hesitant group. Partners’ ethnicity, a low educational level and a low income were significantly associated with vaccine hesitancy amongst pregnant mothers.ConclusionPrevalence of vaccine hesitancy amongst urban Malaysian pregnant women was relatively low. Muslim mothers are less likely to be vaccine hesitant. Educational level of mothers and their partners are the common determinant of vaccine hesitancy amongst antenatal mothers.     

The impact of COVID-19 on income and employment and willingness to become vaccinated among African Americans enrolled in a smoking cessation randomized trial

Given vulnerability to COVID-19 among smokers and vaccine hesitancy among populations disproportionately burdened with COVID-19, it’s important to understand concerns about vaccines and the impact of COVID-19 on these subgroups. Among our all African American (AA) sample of smokers (N = 172) enrolled in a larger smoking cessation clinical trial, results demonstrated an intensive burden from COVID-19; 42 (24.4%) lost employment, 56 (32.6%) lost household income, and 66 (38.4%) reported inability to pay bills and buy food due to COVID. Most, 103 (64.4%), were willing to get vaccinated. Among the vaccine-hesitant, 57 (35.6%), concerns about COVID-19 vaccine development and mistrust in vaccines were primary reasons for unwillingness to get vaccinated. Few identified doctor’s advice as most valued in deciding if the vaccine was the best option. Findings highlight high openness to the vaccine among smokers impacted by COVID but reiterate the need for community-engaged versus health system-driven approaches to improve vaccine hesitancy among racial/ethnic minorities.     

Pertussis vaccination during pregnancy: Antibody persistence in infants

Maternal pertussis vaccination is associated with higher levels of pertussis antibodies at birth. We assessed the persistence of pertussis antibodies until primary vaccination in infants whose mothers received Tdap (tetanus, diphtheria, acellular pertussis) vaccine during pregnancy. Infants were born at the Hospital Clinic of Barcelona (Spain) in November 2014. Anti-PT IgG was determined by ELISA at delivery, between the first and second month of life, and estimated at 2 months of age. The study included 37 infants whose mothers received Tdap between 21 and 38 weeks of gestation. Infants presented a decline in GMC of anti-PT IgG between peripartum and follow-up levels, 52.7 (95% CI 34.7–80.2) versus 7.5 (95% CI 4.2–13.3) at 2 months of age (p < 0.001). The median half-life of maternal antibodies was 47 days. More than half (51.4%) the infants presented detectable anti-PT IgG before the start of primary infant vaccination.     

“Everybody just wants to do what's best for their child”: Understanding how pro-vaccine parents can support a culture of vaccine hesitancy

BackgroundAlthough a large majority of parents vaccinate their children, vaccine hesitancy has become more widespread. It is not well understood how this culture of vaccine hesitancy has emerged and how it influences parents’ decisions about vaccine schedules.ObjectiveWe sought to examine how attitudes and beliefs of parents who self-report as pro-vaccine are developed and contribute to immunization decisions, including delaying or spacing vaccines.MethodsOpen-ended, in-depth interviews (N = 23) were conducted with upper-middle class parents with young children living in Philadelphia. Interview data were coded and key themes identified related to vaccine decision-making.ResultsParents who sought out vaccine information were often overwhelmed by the quantity and ambiguity when interpreting that information, and, consequently, had to rely on their own instinct or judgment to make vaccine decisions. In particular, while parents in this sample did not refuse vaccines, and described themselves as pro-vaccine, they did frequently delay or space vaccines. This experience also generated sympathy for and tolerance of vaccine hesitancy in other parents. Parents also perceived minimal severe consequences for deviating from the recommended immunization schedule.ConclusionThese findings suggest that the rise in and persistence of vaccine hesitancy and refusal are, in part, influenced by the conflicts in the information parents gather, making it difficult to interpret. Considerable deviations from the recommended vaccination schedule may manifest even within a pro-vaccine population due to this perceived ambiguity of available information and resulting tolerance for vaccine hesitancy.     

Evaluation of two vaccine education interventions to improve pertussis vaccination among pregnant African American women: A randomized controlled trial

BackgroundVaccination coverage with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine in pregnancy or immediately postpartum has been low. Limited data exist on rigorously evaluated interventions to increase maternal vaccination, including Tdap. Tailored messaging based on the Elaboration Likelihood Model (ELM) framework has been successful in improving uptake of some public health interventions. We evaluated the effect of two ELM-based vaccine educational interventions on Tdap vaccination among pregnant African American women, a group of women who tend to have lower vaccine uptake compared with other groups.MethodsWe conducted a prospective randomized controlled trial to pilot test two interventions – an affective messaging video and a cognitive messaging iBook – among pregnant African American women recruited during routine prenatal care visits. We measured Tdap vaccination during the perinatal period (during pregnancy and immediately postpartum), reasons for non-vaccination, and intention to receive Tdap in the next pregnancy.ResultsAmong the enrolled women (n = 106), 90% completed follow-up. Tdap vaccination in the perinatal period was 18% in the control group; 50% in the iBook group (Risk Ratio [vs. control group]: 2.83; 95% CI, 1.26–6.37), and 29% in the video group (RR: 1.65; 95% CI, 0.66–4.09). From baseline to follow-up, women’s reported intention to receive Tdap during the next pregnancy improved in all three groups. Among unvaccinated women, the most common reason reported for non-vaccination was lack of a recommendation for Tdap by the woman’s physician.ConclusionsEducation interventions that provide targeted information for pregnant women in an interactive manner may be useful to improve Tdap vaccination during the perinatal period. However, larger studies including multiple racial and ethnic groups are needed to evaluate robustness of our findings.Trial Registration: clinicaltrials.gov Identifier: NCT01740310.     

Lower vaccine uptake amongst older individuals living alone: A systematic review and meta-analysis of social determinants of vaccine uptake

IntroductionVaccination is a key intervention to reduce infectious disease mortality and morbidity amongst older individuals. Identifying social factors for vaccine uptake enables targeted interventions to reduce health inequalities.ObjectiveTo systematically appraise and quantify social factors associated with vaccine uptake amongst individuals aged ≥60 years from Europe.MethodsWe searched Medline and Embase from inception to 24/02/2016. The association of vaccine uptake was examined for social factors relevant at an individual level, to provide insight into individuals’ environment and enable development of targeted interventions by healthcare providers to deliver equitable healthcare. Factors included: living alone, marital status, education, income, vaccination costs, area-level deprivation, social class, urban versus rural residence, immigration status and religion. Between-study heterogeneity for each factor was identified using I²-statistics and Q-statistics, and investigated by stratification and meta-regression analysis. Meta-analysis was conducted, when appropriate, using fixed- or random-effects models.ResultsFrom 11,754 titles, 35 eligible studies were identified (uptake of: seasonal influenza vaccine (SIV) only (n = 27) or including pneumococcal vaccine (PV) (n = 5); herpes zoster vaccine (n = 1); pandemic influenza vaccine (n = 1); PV only (n = 1)). Higher SIV uptake was reported for individuals not living alone (summary odds ratios (OR) = 1.39 (95% confidence interval (CI): 1.16–1.68). Lower SIV uptake was observed in immigrants and in more deprived areas: summary OR = 0.57 (95%CI: 0.47–0.68) and risk ratio = 0.93 (95%CI: 0.92–0.94) respectively. Higher SIV uptake was associated with higher income (OR = 1.26 (95%CI: 1.08–1.47)) and higher education (OR = 1.05 (95%CI: 1–1.11)) in adequately adjusted studies. Between-study heterogeneity did not appear to result from variation in categorisation of social factors, but for education was partly explained by varying vaccination costs (meta-regression analysis p = <0.0001); individuals with higher education had higher vaccine uptake in countries without free vaccination.ConclusionsQuantification of associations between social factors and lower vaccine uptake, and notably living alone (an overlooked factor in vaccination programmes), should enable health professionals target specific social groups to tackle vaccine-related inequalities.