Survey of influenza vaccine knowledge, attitudes, and beliefs among pregnant women in the 2016-17 season

Respiratory syncytial virus knowledge, attitudes, and perceptions among adults in the United States

Respiratory syncytial virus (RSV) is associated with considerable morbidity and mortality among older adults (aged ≥60 years) and adults with certain chronic conditions in the United States (US). Despite this burden, no previous studies have assessed the knowledge, attitudes, and perceptions (KAP) of RSV among these populations. This study evaluates RSV-related KAP among US adults at increased risk of severe RSV infection. A cross-sectional, web-based survey was administered from May to June 2022 to better understand respiratory infection- and RSV-related KAP among US adults who are at risk of severe RSV infection. The survey included ≥200 adults in each of 4 subgroups: adults aged 60-89 years, and adults aged 18-59 years with ≥1 chronic cardiovascular condition, chronic pulmonary condition, or diabetes mellitus. Survey responses were analyzed descriptively overall and by subgroup, with exploratory logistic regression modeling used to evaluate characteristics associated with RSV awareness and concern. Among the 827 survey respondents, only 43.3% had ever heard of RSV (n = 358/827). The study identified key knowledge gaps (e.g. bacterial vs. viral nature of respiratory infections, RSV seasonality, common RSV symptoms, extent to which RSV causes respiratory infections in specific patient populations). Although 33.7% of RSV-aware adults (n = 120/356) reported being worried/very worried about RSV, 67.3% (n = 241/358) rarely consider RSV as a potential cause of their cold/flu-like symptoms. Results from this study highlight important knowledge gaps related to RSV, perceived risk, and severity of RSV. Findings can be used to support the development of tailored education efforts to support RSV prevention.

Prenatal Vaccination Patterns among Birthing Individuals with History of Preterm Birth in the Pre- and Post-COVID Era

OBJECTIVE

This study aims to explore vaccination acceptance among individuals with a history of preterm birth between March and June during the pre-COVID (2019), early-COVID (2020), and late-COVID (2021) periods.

STUDY DESIGN

This is a cross-sectional, retrospective cohort study of pregnant individuals with a history of preterm birth (<37 weeks' gestation) who initiated care of a subsequent pregnancy during pre-COVID (March-June 2019), early-COVID (March-June 2020), or late-COVID (March-June 2021). The primary outcome of interest was vaccination status for influenza, Tdap, and COVID-19 vaccines. Fisher's exact and chi-square tests were used to investigate association between vaccination status and time periods, race/ethnicity, and insurance.

RESULTS

Among 293 pregnancies, influenza vaccination rate was highest in early-COVID (p < 0.05). There was no statistically significant difference in Tdap or COVID-19 vaccination between time periods. COVID-19 vaccination was highest in individuals with private insurance (p < 0.05). There was no statistically significant difference in vaccination status by race/ethnicity.

CONCLUSION

In this study on high-risk pregnant individuals, the majority of our cohort remained unvaccinated against COVID-19 into the late-COVID period. Additionally, their influenza vaccination rates were greater than the national average in early-COVID and substantially lower than the national average in late-COVID. This shift in influenza vaccination acceptance may have been sparked by COVID-19 vaccine distribution beginning in January 2021 leading to overall vaccination hesitancy. Standardized guidelines and counseling concerning prenatal safety in recommended immunizations may serve as important tools of reassurance and health promotion.

KEY POINTS

· Maternal infections during pregnancy are a risk factor for preterm birth.. · High-risk cohort had low influenza vaccination post-COVID possibly due to COVID-19 vaccine hesitancy.. · Vaccination education may be a uniquely important tool among high-risk pregnant patients..

Racial and ethnic disparities in influenza vaccination coverage among pregnant women in the United States: The contribution of vaccine-related attitudes

OBJECTIVE

Racial and ethnic disparities in influenza vaccination coverage among pregnant women in the United States have been documented. This study assessed the contribution of vaccine-related attitudes to coverage disparities.

METHODS

Surveys were conducted following the 2019-2020 and 2020-2021 influenza seasons in a US research network. Using electronic health record data to identify pregnant women, random samples were selected for surveying; non-Hispanic Black women and influenza-unvaccinated women were oversampled. Regression-based decomposition analyses were used to assess the contribution of vaccine-related attitudes to racial and ethnic differences in influenza vaccination. Data were combined across survey years, and analyses were weighted and accounted for survey design.

RESULTS

Survey response rate was 41.2% (721 of 1748) for 2019-2020 and 39.3% (706 of 1798) for 2020-2021. Self-reported influenza vaccination was higher among non-Hispanic White respondents (79.4% coverage, 95% CI 73.1%-85.7%) than Hispanic (66.2% coverage, 95% CI 52.5%-79.9%) and non-Hispanic Black (55.8% coverage, 95% CI 50.2%-61.4%) respondents. For all racial and ethnic groups, a high proportion (generally >80%) reported being seen for care, recommended for influenza vaccination, and offered vaccination. In decomposition analyses, vaccine-related attitudes (e.g., worry about vaccination causing influenza; concern about vaccine safety and effectiveness) explained a statistically significant portion of the observed racial and ethnic disparities in vaccination. Maternal age, education, and health status were not significant contributors after controlling for vaccine-related attitudes.

CONCLUSIONS

In a setting with relatively high influenza vaccination coverage among pregnant women, racial and ethnic disparities in coverage were identified. Vaccine-related attitudes were associated with the disparities observed.

Effect of Primary Care Center Characteristics, Healthcare Worker Vaccination Status and Patient Economic Setting on Patient Influenza Vaccination Coverage Rates

BACKGROUND

Reaching the public health organizations targets of influenza vaccination in at-risk patient groups remains a challenge worldwide. Recognizing the relationship between the healthcare system characteristics and the economic environment of the population with vaccination uptake can be of great importance to improve.

METHODS

Several characteristics were correlated in this retrospective ecological study with data from 6.8 million citizens, 15,812 healthcare workers across 258 primary care health centers, and average income by area of the care center in Spain.

RESULTS

No correlation between HCW vaccination status and patient vaccination was found. A weak negative significant correlation between the size of the population the care center covers and their vaccination status did exist (6 mo.-59 yr., r = 0.19, p = 0.002; 60-64 yr., r = 0.23, p < 0.001; ≥65 yr., r = 0.23, p ≥ 0.001). The primary care centers with fewer HCWs had better uptake in the at-risk groups in the age groups of 60-64 yr. (r = 0.20, p = 0.002) and ≥65 (r = 0.023, p ≥ 0.001). A negative correlation was found regarding workload in the 6 mo.-59 yr. age group (r = 0.18, p = 0.004), which showed the at-risk groups that lived in the most economically deprived areas were more likely to be vaccinated.

CONCLUSIONS

This study reveals that the confounding variables that determine influenza vaccination in a population and in HCWs are complex. Future influenza campaigns should address these especially considering the possibility of combining influenza and SARS-CoV-2 vaccines each year.

Prenatal tetanus-diphtheria-acellular pertussis vaccine effectiveness at preventing infant pertussis

OBJECTIVE

To evaluate the effectiveness of the tetanus, diphtheria, and acellular pertussis (Tdap) vaccine containing five pertussis components (Tdap5; Adacel®, Sanofi) when given during pregnancy at preventing pertussis in infants less than 2 months of age.

METHODS

The US Centers for Disease Control and Prevention (CDC), in collaboration with the Emerging Infections Program (EIP) Network, undertook a case-control study evaluating the effectiveness of Tdap vaccination in pregnancy against pertussis in infants less than 2 months of age based on data collected by the EIP Network from 2011 through 2014. The dataset from the CDC/EIP Network study was used to conduct this product-specific vaccine effectiveness analysis of Tdap5 vaccination in pregnancy to prevent disease in young infants. The main outcome of interest was vaccine effectiveness in infants whose pregnant parents were vaccinated with Tdap5 between 27 and 36 weeks' gestation, in accordance with the ideal timing for Tdap vaccination in pregnancy recommended by the US Advisory Committee on Immunization Practices. Odd ratios (ORs) and 95 % confidence intervals (CIs) were estimated using conditional logistic regression, and vaccine effectiveness was calculated as (1-OR) × 100 %.

RESULTS

There were 160 infant pertussis cases and 302 matched controls included in this Tdap5-specific study. Tdap5 effectiveness in preventing pertussis in infants whose pregnant parents were vaccinated between 27 and 36 weeks' gestation was 92.5 % (95 % CI, 38.5 %-99.1 %). Effectiveness of Tdap5 against pertussis-related hospitalization in infants whose pregnant parents were vaccinated between 27 and 36 weeks' gestation could not be calculated due to lack of discordance among matched cases and controls. Vaccination of the parents after pregnancy or less than 14 days before delivery did not protect infants from pertussis.

CONCLUSIONS

Tdap5 vaccination in pregnancy between 27 and 36 weeks' gestation is highly effective at protecting young infants from pertussis.

STUDY REGISTRATION

ClinicalTrials.gov, NCT05040802.

Knowledge, attitudes, and practices regarding seasonal influenza vaccination during pregnancy in Costa Rica: A mixed-methods study

BACKGROUND

Influenza increases stillbirth risk, morbidity and mortality in pregnant women. Vaccination protects pregnant women against severe disease and indirectly protects their infants, but coverage among pregnant women remains low worldwide. We aimed to describe knowledge, attitudes, and practices (KAP) regarding seasonal influenza vaccination among postpartum women and prenatal care physicians in Costa Rica.

METHODS

We conducted cross-sectional KAP surveys to women one to three days after childbirth at Costa Rican Social Security Fund maternity hospitals, and obstetricians and general practitioners who provided prenatal care in 2017. Principal components analysis, multiple imputation, and logistic regression were used to examine associations between influenza vaccination and demographics, prenatal care, and sources of information-separately for postpartum women and physicians. We also held two focus groups of six healthcare workers each to further describe vaccination KAP.

RESULTS

We surveyed 642 postpartum women and 146 physicians in maternity hospitals in five Costa Rican provinces of whom 85.5 % (95 % CI: 82.6 %-88.0 %) and 57.9 % (95 % CI: 49.6 %-65.7 %) were vaccinated for influenza, respectively. Factors associated with influenza vaccination for postpartum women included tetanus vaccination (aOR: 3.62, 95 % CI: 1.89-6.92); received vaccination recommendations from clinicians during prenatal check-ups (aOR: 3.39, 95 % CI: 2.06-5.59); had other children in household vaccinated for influenza (aOR: 2.25, 95 % CI: 1.08-4.68); and secondary/university education (aOR: 0.15-0.31) with no formal education as reference. For postpartum women, reasons for vaccination were perceived benefits for mother and infant, whereas not being offered vaccines was most cited for non-vaccination. Most prenatal care physicians recommended influenza vaccines during prenatal check-ups but believed vaccination causes flu-like symptoms.

CONCLUSION

Vaccination campaigns and provisions of free vaccines effectively increased knowledge and coverage among women in Costa Rica. To improve access, women should be offered vaccines during prenatal care appointments. Educating healthcare workers about vaccine benefits for themselves and patients is needed to mitigate safety concerns.

SARS-CoV-2 vaccine uptake and reasons for hesitancy among Canadian pregnant people: a prospective cohort study

BACKGROUND

Several vaccines against SARS-CoV-2 have been developed and approved at an unparalleled speed. Given that SARS-CoV-2 vaccines are recommended to pregnant people, our aim was to quantify vaccination uptake, and describe vaccination hesitancy and behavioural attitudes surrounding SARS-CoV-2 vaccination in pregnancy in Canada.

METHODS

The CONCEPTION study is an ongoing international study started in June 2020, evaluating the impact of the COVID-19 pandemic on the health of pregnant people and their children. For this study, pregnant people recruited from Apr. 20, 2021, to Feb. 8, 2022, and residing in Canada were invited to complete a Web-based survey. In addition to all CONCEPTION variables, data on vaccine uptake as well as personal knowledge of COVID-19 severity in pregnancy and of SARS-CoV-2 vaccine safety and efficacy were collected. Marginal risk differences and adjusted odds ratios (ORs) were calculated to assess determinants of SARS-CoV-2 vaccination during pregnancy.

RESULTS

From Apr. 20, 2021, to Feb. 8, 2022, 603 pregnant people were recruited and gave consent, of which 83.7% (n = 505) were vaccinated and 16.3% (n = 98) were not vaccinated against SARS-CoV-2. Uptake of the influenza vaccine in 2020/21 was a significant predictor of being vaccinated against SARS-CoV-2 or intention to be vaccinated (marginal risk difference 3.2%, 95% confidence interval [CI] 3.0% to 3.3%, adjusted OR 4.43, 95% CI 2.32 to 9.25), and being employed (marginal risk difference 11.2%, 95% CI 10.6% to 11.9%, adjusted OR 2.17, 95% CI 1.03 to 4.35) increased the likelihood of being vaccinated against SARS-CoV-2. Self-assessed knowledge of COVID-19 severity and vaccine efficacy was not associated with vaccine uptake.

INTERPRETATION

Among the Canadian pregnant people who responded to this study, vaccine uptake against SARS-CoV-2 was high. However, our results underscore the importance of improving knowledge transfer about the efficacy of SARS-CoV-2 vaccines in pregnancy to guide vaccination efforts.

Understanding drivers of influenza vaccine hesitancy among pregnant women in China: evidence from an extended theory of planned behavior

BACKGROUND

Pregnant women have a low uptake of influenza vaccination, although being recommended as a priority.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional questionnaire survey in China from June to July 2021. Hierarchical regression analysis and structural equation modeling were performed based on the extended theory of planned behavior, in which attitudes, subjective norms, perceived behavioral control, and intention each affect the vaccine hesitancy; four variables of response efficacy, knowledge, vulnerability, and severity were added as extended dimensions; vaccination history played a moderator role in this model-to test the validity of the framework.

RESULTS

Totally, 1283 pregnant women participated in this study. The intention existed as a mediator between attitude [β_indirect=0.142 (95% confidence interval (CI): 0.084, 0.206), P<0.001], subjective norms [β_indirect=0.568 (95%CI: 0.424, 0.754), P<0.001], perceived behavioral control [β_indirect=0.070 (95%CI: 0.025, 0.118), P=0.004] and vaccine hesitancy. Further, the differences in indirect effect between the two dimensions of attitude (P<0.001), perceived behavioral control (P<0.001), and subjective norms were each statistically significant. Vaccination history did not moderate the association between attitude (P=0.679), subjective norms (P=0.645), and hesitancy.

CONCLUSIONS

The subjective norms dimension has a strong association with influenza vaccine hesitancy. Vaccination history had limited ability to reduce hesitancy during pregnancy.

Influenza vaccination during pregnancy and risk of selected major structural noncardiac birth defects, National Birth Defects Prevention Study 2006-2011

PURPOSE

To assess associations between influenza vaccination during etiologically-relevant windows and selected major structural non-cardiac birth defects.

STUDY DESIGN

We analyzed data from the National Birth Defects Prevention Study, a multisite, population-based case-control study, for 8233 case children diagnosed with a birth defect and 4937 control children without a birth defect with delivery dates during 2006-2011. For all analyses except for neural tube defects (NTDs), we classified mothers who reported influenza vaccination 1 month before through the third pregnancy month as exposed; the exposure window for NTDs was 1 month before through the first pregnancy month. For defects with five or more exposed case children, we used logistic regression to estimate propensity score-adjusted odds ratios (aORs) and 95% confidence intervals (CIs), adjusting for estimated delivery year and season; plurality; maternal age, race/ethnicity, smoking and alcohol use, low folate intake; and, for NTDs, folate antagonist medications.

RESULTS

There were 334 (4.1%) case and 197 (4.0%) control mothers who reported influenza vaccination from 1 month before through the third pregnancy month. Adjusted ORs ranged from 0.53 for omphalocele to 1.74 for duodenal atresia/stenosis. Most aORs (11 of 19) were ≤1 and all adjusted CIs included the null. The unadjusted CIs for two defects, hypospadias and craniosynostosis, excluded the null. These estimates were attenuated upon covariate adjustment (hypospadias aOR: 1.25 (95% CI 0.89, 1.76); craniosynostosis aOR: 1.23 (95% CI: 0.88, 1.74)).

CONCLUSIONS

Results for several non-cardiac major birth defects add to the existing evidence supporting the safety of inactivated influenza vaccination during pregnancy. Under-reporting of vaccination may have biased estimates downward.

Association Between Influenza Vaccination During Pregnancy and Breastfeeding Duration

Background: Prenatal vaccination and breastfeeding are both health promotional behaviors. The benefits of breastfeeding are widely investigated and well established, as well as the effectivity and the safety of the influenza vaccination. This study aimed to investigate the association between the prenatal health behavior of influenza vaccination and breastfeeding duration for at least 3 months in the United States. Methods: A secondary data analysis was conducted using 2016-2019 Pregnancy Risk Assessment and Monitoring System data consisting of 83,976 postpartum women. Results: Overall, 68.3% (n = 57,269) breastfed for at least 3 months and 56.6% (n = 48,834) received the influenza vaccine during pregnancy. Women who did not receive the influenza vaccine during pregnancy were significantly less likely to breastfeed compared with women who received the vaccine during pregnancy (64.5% versus 71.1%; p < 0.001). Significant covariates associated with ≥3-month breastfeeding duration included maternal sociodemographic factors, infant factors, maternal health factors, and prenatal health behaviors. In the multivariable logistic regression analyses, the odds of breastfeeding at least 3 months were significantly lower in women who did not receive the influenza vaccine during pregnancy compared with those who were vaccinated (odds ratio, 0.92; 95% confidence interval, 0.88-0.98; p = 0.005). Discussion: Findings from this large, nationally representative sample of U.S. mothers indicate an association between the health-promotional behaviors of prenatal influenza vaccination and breastfeeding duration postpartum. Recommendations and education by health care providers should include a focus on maternal health behaviors to support positive maternal-infant health outcomes including reduced risk of infection and extended breastfeeding duration.

Assessment of factors affecting attitudes and knowledge of pregnant women about COVID-19 vaccination

The aim of this study was to analyse knowledge and attitudes of pregnant women about Coronavirus disease (COVID-19) and its vaccine. Pregnant women who attended outpatient maternal care between October 2020 and March 2021 were invited to participate in this cross-sectional survey study. To identify the effect of baseline characteristics of participants on their vaccination decision, the pregnant women were divided into two groups as accepting or rejecting the COVID-19 vaccine. The Multiparity rate was significantly higher in the rejection group (73.8 vs. 42.3, p = .001). Education level and rate of employment in the professional health sector were significantly higher in the acceptance group (p = .001 and p = .008). A total of 103 (26.4%) pregnant women from the acceptance group, and 23 (10.9%) from the rejection group had a history of the death of relatives and acquaintances from COVID-19 (p = .001). The present study demonstrated that nulliparous status, higher education level, working as a professional healthcare provider and incidence of death in relatives due to COVID-19 significantly rise pregnant women's acceptance of the COVID-19 vaccine. Considering the overall acceptance rate of 65%, improved vaccination programmes using all types of information sources need to be the main task to block the COVID-19 pandemic. IMPACT STATEMENTWhat is already known on this subject? There are previous studies that evaluated the attitudes and beliefs about several vaccine types among pregnant women. An important part of tackling the COVID-19 pandemic is the success of the COVID-19 vaccination program in pregnant women. In this respect, it is important to know the attitudes of pregnant women regarding COVID-19 vaccination.What do the results of this study add? The baseline characteristics of pregnant women with or without acceptance of COVID-19 vaccination were similar regarding COVID-19 infection. The rates of being not multiparous and a health worker were higher in women with acceptance of COVID-19 vaccination. The rate of loss of relatives was also higher in women with acceptance of COVID-19 vaccination. In women without acceptance of COVID-19 vaccination, the major drawback was related to the possibility of harm to their baby's and own health.What are the implications of these findings for clinical practice and/or further research? In pregnant women, the attitude to COVID-19 vaccination may be modifiable by the design of focussed information media with respect to their education, occupation, and parity. Longitudinal studies are needed to determine whether this approach can effectively increase the rate of COVID-19 vaccination in pregnant women.

Vaccination in pregnancy against pertussis and seasonal influenza: key learnings and components from high-performing vaccine programmes in three countries: the United Kingdom, the United States and Spain

BACKGROUND

Pertussis and seasonal influenza are responsible for significant maternal, neonatal, and infant morbidity and mortality, but vaccine coverage rates (VCR) for both pertussis (administered as a tetanus, diphtheria, acellular pertussis [Tdap] vaccination) and seasonal influenza in pregnancy remain generally low. Only a small number of countries, including Spain, the United Kingdom (UK), and the United States (US), have high Tdap and seasonal influenza VCRs in pregnancy. The purpose of this study was to identify the key factors that contributed to the high VCRs observed in these countries.

METHODS

The experience from both Tdap and seasonal influenza vaccination programmes during pregnancy were documented in Spain, the UK, and the US using a three-step approach. A literature review yielded 157 publications, and a further 117 documents were selected through desk research. A published five-pillar VCR framework for influenza was amended to evaluate the specific contributing factors leading to high Tdap and seasonal influenza VCRs among pregnant women.

RESULTS

The analysis identified components that contributed to higher VCR in pregnant women across three different healthcare systems in Spain, UK, and US. The combination of several key interventions in each country led to a rapid increase in VCR that reached near-optimal levels (i.e. 75% for seasonal influenza) within a few years. As well as inclusion in national immunisation programme and vaccine reimbursement, key components that were identified included the mobilisation of health authorities, prenatal care Healthcare Professionals (HCP) and scientific societies, the inclusion of vaccination in antenatal medical guidance, the provision of educational material to HCPs, and a strong disease awareness driven by recent pertussis outbreaks in each country.

CONCLUSIONS

Although there is no simple, universal solution to improving sub-optimal VCRs, the list of components identified in this study from three countries with high-performing Tdap and seasonal influenza vaccination programmes provides a basis for public health and medical stakeholders in other countries to define strategies to successfully implement national vaccination programmes for pregnant women.

Prevalence of and factors associated with receipt of provider recommendation for influenza vaccination and uptake of influenza vaccination during pregnancy: cross-sectional study

BACKGROUND

Seasonal influenza vaccination has been recommended for pregnant women in Germany since 2010. The aim of this study was to examine prevalence and determinants of receipt of provider recommendation for influenza vaccination as well as influenza vaccination uptake during pregnancy.

METHODS

We analysed data from the "KUNO Kids Health Study", a prospective birth cohort. During the study period (5th July 2015 to 27th June 2018) data were collected from participating mothers by interview and questionnaire. According to Andersen's behavioural model of health services use potential influencing factors describing the circumstances and characteristics of the mothers and their pregnancies which are potentially affecting whether women receive a recommendation for a vaccination or whether they utilize influenza vaccination were classified into three domains: 'predisposing characteristics', 'enabling resources' and 'need'. Using multivariable logistic regression models odds ratios (OR) and corresponding 95% confidence intervals (95% CI) were calculated.

RESULTS

As a combined result across three flu seasons, 368 of 1814 (20.3%) women received an influenza vaccination recommendation during pregnancy. Having had a high-risk pregnancy increased the odds of receiving a vaccination recommendation (OR = 1.3; 95% CI = 1.0-1.6; p = 0.045). In contrast, pregnancy onset in summer (OR = 0.7; 95% CI = 0.5-1.0; p = 0.027), autumn (OR = 0.4; 95% CI = 0.3-0.5; p < =0.001) or winter (OR = 0.5; 95% CI = 0.3-0.6; p < =0.001) (compared to spring) as well as mother's birthplace outside Germany (OR = 0.6; 95% CI = 0.4-0.9; p = 0.023) reduced the chance of getting a vaccination recommendation. Two hundred forty-two of one thousand eight hundred sixty-five (13%) women were vaccinated against influenza during pregnancy. Having received a vaccination recommendation was strongly associated with vaccination uptake (OR = 37.8; 95% CI = 25.5-55.9; p < =0.001). Higher health literacy status was also associated with a higher chance of vaccination uptake (OR = 1.7; 95% CI = 1.2-2.6; p = 0.008), whereas pregnancy onset in autumn (compared to spring) reduced the chance (OR = 0.5; 95% CI = 0.3-0.8; p = 0.008).

CONCLUSIONS

At 13% the uptake rate of influenza vaccination is low. Having received a recommendation to vaccinate was strongly associated with uptake but only one fifth of all mothers report such a recommendation. Raising awareness in physicians regarding vaccinating during pregnancy seems to be of essential importance to increase vaccine uptake and to prevent influenza-related complications in pregnant women.