Determinants of uptake of influenza vaccination among pregnant women - a systematic review

Knowledge and attitudes towards influenza and influenza vaccination among pregnant women in Kenya

BACKGROUND

Influenza vaccination during pregnancy benefits mothers and children. Kenya and other low- and middle-income countries have no official influenza vaccination policies to date but are moving towards issuing such policies. Understanding determinants of influenza vaccine uptake during pregnancy in these settings is important to inform policy decisions and vaccination rollout.

METHODS

We interviewed a convenience sample of women at antenatal care facilities in four counties (Nairobi, Mombasa, Marsabit, Siaya) in Kenya. We described knowledge and attitudes regarding influenza vaccination and assessed factors associated with willingness to receive influenza vaccine.

RESULTS

We enrolled 507 pregnant women, median age was 26 years (range 15-43). Almost half (n = 240) had primary or no education. Overall, 369 (72.8%) women had heard of influenza. Among those, 288 (78.1%) believed that a pregnant woman would be protected if vaccinated, 252 (68.3%) thought it was safe to receive a vaccine while pregnant, and 223 (60.4%) believed a baby would be protected if mother was vaccinated. If given opportunity, 309 (83.7%) pregnant women were willing to receive the vaccine. Factors associated with willingness to receive influenza vaccine were mothers' belief in protective effect (OR 3.87; 95% CI 1.56, 9.59) and safety (OR 5.32; 95% CI 2.35, 12.01) of influenza vaccines during pregnancy.

CONCLUSION

Approximately one third of pregnant women interviewed had never heard of influenza. Willingness to receive influenza vaccine was high among women who had heard about influenza. If the Kenyan government recommends influenza vaccine for pregnant women, mitigation of safety concerns and education on the benefits of vaccination could be the most effective strategies to improve vaccine acceptance.

Pregnant women's perspectives about maternal immunization in Latin America

BACKGROUND

Maternal immunization rates and vaccine uptake in Latin America vary from country to country. This variability stems from factors related to pregnant women, vaccine recommendations from healthcare providers and the health system. The aim of this paper is to describe women's knowledge and attitudes to maternal immunziation, and barriers to access and vaccination related decision-making processes in Latin American countries.

METHODS

We conducted focus group discussions (FGD) with pregnant women in five middle-income countries: Argentina, Brazil, Honduras, Mexico and Peru, between July 2016 and July 2018. The FGDs were conducted by trained qualitative researchers in diverse clinics located in the capital cities of these countries.

RESULTS

A total of 162 pregnant women participated in the FGDs. In general, participants were aware of the recommendation to receive vaccines during pregnancy but lacked knowledge regarding the diseases prevented by these vaccines. Pregnant women expressed a desire for clearer and more detailed communication on maternal vaccines by their healthcare professionals instead of relying on other sources of information such as the internet. Overall, participants had positive attitudes towards maternal immunization and were open to receiving vaccines in pregnancy based on general trust they have in recommendations made by their healthcare providers. The main obstacles pregnant women said they encounter were mainly centered around their clinical experience: long waiting times, vaccine shortages, and impolite behavior of healthcare providers or clinical staff.

CONCLUSION

Important advances have been made in Latin America to promote maternal immunization. Results from this study show that an important aspect that remains to be addressed, and is crucial in improving vaccine uptake in pregnancy, is women's clinical experience. We recommend pregnant women to be treated as a priority population for providing immunization and related healthcare education. It is imperative to train healthcare providers in health communication so they can effectively communicate with pregnant women regarding maternal vaccines and can fill knowledge gaps that otherwise might be covered by unreliable sources dispensing inaccurate information.

Maternal vaccinations coverage and reasons for non-compliance - a cross-sectional observational study

BACKGROUND

Maternal influenza and pertussis vaccinations have been proven safe and effective in reducing maternal and infant morbidity and mortality. Though recommended, not all pregnant women receive these important vaccines. We aimed to evaluate the vaccine coverage of maternal immunization in pregnancy for seasonal influenza and acellular pertussis and elucidate the reasons for non-vaccination among pregnant women. The secondary objective was to describe factors that affect vaccine uptake.

METHODS

A cross sectional observational study using anonymous questionnaires distributed to women in the maternity ward or pregnant women hospitalized in the high-risk ward, between Nov 2017 and June 2018, In an Israeli tertiary hospital.

RESULTS

Of 321 women approached, 313 were eligible, with a total of 290 women completing the questionnaire (92.6%). We found a 75.9% (95% CI 71-81) and 34.5% (95% CI 29-40) vaccination rate for pertussis and influenza vaccines, respectively. The most prominent reason for not receiving the pertussis vaccine was being under-informed (24%). Influenza vaccine was not received mainly due to concerns about vaccine efficacy (28%). Other factors influencing vaccine uptake included education, prior childbirth and vaccine recommendations made by the provider.

CONCLUSION

Although maternal vaccination of pertussis and influenza is officially recommended, vaccine uptake is suboptimal. Our study suggests a central role for medical providers in diminishing the concerns about safety and efficacy, and presents novel factors influencing compliance rates, like seasonality and number of prior births.

Enablers and barriers of maternal and neonatal immunization programs in Latin America

BACKGROUND

The Region of the Americas has a long history of implementing maternal and neonatal immunization (MNI) programs. Our study aimed to understand the state of MNI policies, strategies and implementation practices in Latin America (LA).

METHODS

Study conducted in 5 middle-income countries: Argentina, Brazil, Honduras, Mexico and Peru. The methods included a desk review, interviews with national stakeholders and health care providers, focus groups with pregnant women and observations in health facilities. Enablers and barriers were identified and categorized as individual, societal or related to the health system.

RESULTS

All 5 participating countries had similar MNI policies and high access to antenatal care. Key enablers were the high acceptability of vaccination during pregnancy, high-level of political will and a national legal framework ensuring free access to vaccines. At the health system level, implementation was facilitated by the existence of immunization advisory committees, a pooled vaccine procurement mechanism, complementary vaccine delivery strategies, conditional cash transfer to users and performance incentives to health facilities. The main programmatic barriers were the lack of adequate MNI information; limited coordination between antenatal and immunization services; inadequate supply, resources and infrastructure; high staff turnover; insufficient training for health care providers; and weak monitoring and reporting systems.

CONCLUSION

Middle-income countries in LA have successfully implemented MNI programs and several enablers were identified. To overcome remaining barriers, there is a need to focus on improving the "immunization journey" for pregnant women through providing more clear and timely information to users and providers; removing barriers to access; ensuring adequate supply, human resources and infrastructure; making the health service experience positive; and establishing integrated information systems that allow for monitoring the progress toward achieving MNI goals. Strengthening the MNI programs can also improve equitable access to health services and prepare for the introduction of future vaccines for pregnant women.

Safety and protective effects of maternal influenza vaccination on pregnancy and birth outcomes: A prospective cohort study

BACKGROUND

Our study aimed to assess the safety and protective effect of maternal influenza vaccination on pregnancy and birth outcomes.

METHODS

The study population comprised 1253 healthy nulliparous pregnant women in South Australia between 2015 and 2018. Participants were followed prospectively, with vaccination status (confirmed by medical records), pregnancy, and birth outcome data collected by midwives. Adjusted relative risks (aRRs) and adjusted hazard ratios (aHRs) were estimated accounting for time-varying vaccine exposure and temporal nature of each outcome.

FINDINGS

Maternal influenza vaccination (48%, 603 of 1253) reduced the risk for pre-delivery hospitalisation with influenza like illness (aHR 0•61; 95% CI 0•39, 0•97). Maternal influenza vaccination was not associated with spontaneous abortion (aHR 0•42, 95% CI 0•12, 1•45), chorioamnionitis (aRR 0•78, 95% CI, 0•32, 1•88), gestational hypertension (aHR 0•78, 95% CI 0•47, 1•29), pre-eclampsia (aHR 0.84, 95% CI 0•54, 1•27), gestational diabetes (aHR 1•16, 95% CI 0•82, 1•66) nor preterm birth (aHR 0•94, 95% CI 0•59, 1•49). No associations between antenatal influenza vaccination and congenital anomalies, admission to the neonatal care unit, low Apgar scores, and mechanical ventilation were observed. Results were not materially changed after adjustment for pertussis vaccination. We observed a protective effect of maternal influenza vaccination on low birth weight (aHR 0•46, 95% CI 0•23, 0•94) and a marginal protective effect on small for gestational age births (aHR 0•65, 95% CI 0•40, 1•04) during periods of high influenza activity.

INTERPRETATION

These results support the safety of maternal influenza vaccination and suggest a protective effect in reducing the rates of low birthweight and small for gestational age births.

FUNDING

There was no funding for this study.

Pertussis and influenza immunisation coverage of pregnant women in New Zealand

BACKGROUND

Immunisation is an important public health policy and measuring coverage is imperative to identify gaps and monitor trends. New Zealand (NZ), like many countries, does not routinely publish coverage of immunisations given during pregnancy. Therefore, this study examined pregnancy immunisation coverage of all pregnant NZ women between 2013 and 2018, and what factors affected uptake.

METHODS

A retrospective cohort study of pregnant women who delivered between 2013 and 2018 was undertaken using administrative datasets. Maternity and immunisation data were linked to determine coverage of pertussis and influenza vaccinations in pregnancy. Generalised estimating equations were used to estimate the odds of receiving a vaccination during pregnancy.

RESULTS

From 2013 to 2018 data were available for 323,622 pregnant women, of whom 21.7% received maternal influenza immunisations and 25.7% maternal pertussis immunisations. Coverage for both vaccines increased over time, pertussis increased from 10.2% to 43.6% and influenza from 11.2% to 30.8%. The odds of being vaccinated, with either vaccine, during pregnancy increased with increasing age and decreasing deprivation. Compared to NZ European or Other women, Māori and Pacific women had lower odds of receiving a maternal pertussis (OR:0.55, 95% CI: 0.54, 0.57; OR:0.60, 95% CI: 0.58, 0.62, respectively) and influenza (OR: 0.69, 95% CI: 0.67, 0.71; OR:0.90, 95% CI: 0.87, 0.94, respectively) immunisations during pregnancy. Women were also more likely to be vaccinated against pertussis if they received antenatal care from a General Practitioner or Obstetrician compared to a Midwife. A similar pattern was seen for influenza vaccination.

CONCLUSION

Gaps in maternal coverage for pertussis and influenza exist and work is needed to reduce immunisation inequities.

Determinants of pregnant women's knowledge about influenza and the influenza vaccine: A large, single-centre cohort study

Introduction

Although influenza can lead to adverse outcomes during pregnancy, the level of influenza vaccine coverage among pregnant women remains very low. According to the literature, a high level of knowledge about influenza disease and the influenza vaccine is one of the main determinants of vaccination coverage. The objective of the present study was to describe pregnant women’s level of knowledge of these topics and to identify any corresponding determinants.

Material and methods

A prospective, observational, hospital-based study of women having given birth in our university medical centre during the 2014–2015 influenza season. Data were collected through a self-questionnaire or extracted from medical records. Determinants of highest knowledge were identified using logistic regression.

Results

Of the 2069 women included in the study, 827 (40%) did not know that influenza can lead to severe adverse outcomes for the mother, and 960 (46%) did not know about possible severe adverse outcomes for the baby. Two hundred and one women (9.8%) stated that the vaccine was “contraindicated” or “unnecessary” during pregnancy. Only 205 women (17%) had been vaccinated during a previous pregnancy. Determinants of the highest level of knowledge were age over 24, a high educational level, previous influenza vaccination, nulliparity, and the recommendation of vaccination by a healthcare professional.

Conclusions

Recommending vaccination during pregnancy appears to increase knowledge about influenza and its vaccine among pregnant women.

Factors that influence vaccination decision-making among pregnant women: A systematic review and meta-analysis

BACKGROUND

The most important factor influencing maternal vaccination uptake is healthcare professional (HCP) recommendation. However, where data are available, one-third of pregnant women remain unvaccinated despite receiving a recommendation. Therefore, it is essential to understand the significance of other factors and distinguish between vaccines administered routinely and during outbreaks. This is the first systematic review and meta-analysis (PROSPERO: CRD 42019118299) to examine the strength of the relationships between identified factors and maternal vaccination uptake.

METHODS

We searched MEDLINE, Embase Classic & Embase, PsycINFO, CINAHL Plus, Web of Science, IBSS, LILACS, AfricaWideInfo, IMEMR, and Global Health databases for studies reporting factors that influence maternal vaccination. We used random-effects models to calculate pooled odds ratios (OR) of being vaccinated by vaccine type.

FINDINGS

We screened 17,236 articles and identified 120 studies from 30 countries for inclusion. Of these, 49 studies were eligible for meta-analysis. The odds of receiving a pertussis or influenza vaccination were ten to twelve-times higher among pregnant women who received a recommendation from HCPs. During the 2009 influenza pandemic an HCP recommendation increased the odds of antenatal H1N1 vaccine uptake six times (OR 6.76, 95% CI 3.12-14.64, I2 = 92.00%). Believing there was potential for vaccine-induced harm had a negative influence on seasonal (OR 0.22, 95% CI 0.11-0.44 I2 = 84.00%) and pandemic influenza vaccine uptake (OR 0.16, 95% CI 0.09-0.29, I2 = 89.48%), reducing the odds of being vaccinated five-fold. Combined with our qualitative analysis the relationship between the belief in substantial disease risk and maternal seasonal and pandemic influenza vaccination uptake was limited.

CONCLUSIONS

The effect of an HCP recommendation during an outbreak, whilst still powerful, may be muted by other factors. This requires further research, particularly when vaccines are novel. Public health campaigns which centre on the protectiveness and safety of a maternal vaccine rather than disease threat alone may prove beneficial.

The faces of influenza vaccine recommendation: A Literature review of the determinants and barriers to health providers' recommendation of influenza vaccine in pregnancy

INTRODUCTION

WHO recommends influenza vaccination for pregnant women and health providers (HPs), yet global uptake for both is persistently low. Research suggests that HPs greatly influence uptake of influenza vaccine in pregnant women. Our review studies HPs' recommendation of influenza vaccine to pregnant women, determinants and barriers to recommendation, and the role that HPs may play in global influenza vaccine coverage.

METHODS

We undertook a comprehensive global review of literature relating to HPs' recommendation of seasonal influenza vaccines to pregnant women and the determinants and barriers to recommendation and how this may vary by country and context. We evaluated data from each study including frequency of HP recommendation, vaccine coverage, determinants and barriers to recommendation, and the odds of recommending. We tracked the frequency of determinants and barriers to recommendation in heat maps and organized data by world regions and income classifications.

RESULTS

From 32 studies in 15 countries, we identified 68 determinants or barriers to HPs' recommendation. Recommendation rates were highest (77%) in the Americas and lowest in South East Asia (18%). A HP's own influenza vaccine status was a main determinant of recommendation in multiple country contexts and from different provider types. Financial barriers to recommendation were present in higher-income countries and policy-related barriers were highlighted in lower-income countries. HP perceptions of safety, efficacy, and the utility of vaccine were the most frequently cited barriers, relevant in almost every context.

CONCLUSIONS

HP recommendation is important to influenza vaccine implementation in pregnant women. A HP's own status is an important recommendation determinant in multiple contexts. Vaccine program implementation plans should consider the impact of HPs' knowledge, awareness and vaccine confidence on their own uptake and recommendation practices, as well as on the uptake among pregnant women. Addressing safety and efficacy concerns is relevant in all contexts for HPs and pregnant women.

Influenza Vaccination Experiences of Pregnant Women as a Predictor of the Intention to Become Vaccinated in Future Pregnancies in Spain

A good perception of the vaccines administered during pregnancy favors immunization coverage, which is still not optimal for the influenza vaccine. To understand the predisposition towards vaccination in future pregnancies, a study was performed that evaluated the experiences of women with the vaccine or influenza. A cross-sectional study was conducted through telephone interviews given to a total of 683 postpartum women in two health departments from the Valencia Community (Spain). This interview asked about their intention of becoming vaccinated in future pregnancies and whether they were favor or against vaccination. Most of them, 98.5% (n = 673 [95% CI: 97.6–99.4]) (p < 0.001) declared having received the systematic vaccines throughout their lives. The ones who were vaccinated against influenza, 91.9% (n = 387 [95% CI: 89.2–94.6]) (p < 0.001) manifested they would do so in future pregnancies. The probability of future non-vaccination was modeled, which was related to an unfavorable opinion towards vaccines (OR = 4.07 [95% CI: 2.01–8.24]) (p < 0.001), having suffered from influenza during pregnancy (OR = 3.84 [95% CI: 1.41–10.42]) (p < 0.05), and not having been vaccinated during previous pregnancies (OR = 38.47 [95% CI: 23.58–62.76]) (p < 0.001). Vaccination during pregnancy increases the intent of vaccination in the future.

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

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

Antenatal vaccine uptake: A cross-sectional study investigating factors influencing women's choices in pregnancy

BACKGROUND

Seasonal influenza and pertussis cause significant morbidity and mortality among expectant mothers and infants. Vaccination during the antenatal period is an important public health intervention, minimising rates of maternal, neonatal and infant infection.

AIMS

The primary aim of this project was to establish the rates of antenatal vaccine uptake. Secondly, the study aimed to determine socio-demographic factors significant to vaccine uptake. Thirdly, the project aimed to produce a thematic analysis of the factors affecting vaccination uptake during pregnancy.

MATERIALS AND METHODS

A cross-sectional observational study was conducted among women attending a large maternity hospital, in the western suburbs of Melbourne, for perinatal care. Data were collected via self-completed questionnaires after delivery. Data from the questionnaires were entered into an electronic database, and STATA was used to undertake correlation analysis.

RESULTS

Over a 12-month period 1678 women completed questionnaires and 1305 were eligible for further analysis. The uptake of influenza vaccine was 48.3%, pertussis vaccine uptake was higher, at 82.9%. Uptake of influenza and pertussis vaccines strongly correlated with recommendations from healthcare providers (odds ratios 29.7 and 63.8 respectively). Maternal country of birth, age and parity were significant predictors of vaccine uptake. In thematic analysis, healthcare provider recommendation and the perceived risk of the disease were factors resulting in vaccination.

CONCLUSION

This study determined the rate of antenatal vaccine uptake and significant socio-demographic determinants affecting uptake at a large maternity hospital in metropolitan Melbourne. Ensuring healthcare providers recommend vaccination is likely to improve coverage.

Seasonal Influenza Vaccination Patterns Among Pregnant Women in New Mexico

Introduction:

Seasonal influenza vaccination is recommended for pregnant women, but half of the pregnant women in the United States remain unvaccinated. Vaccine coverage in U.S.–Mexico border states has not been examined in depth even though risk factors for low vaccine coverage exist in these states, especially in the counties bordering Mexico.

Method:

Using 2012-2014 New Mexico (NM) Pregnancy Risk Assessment and Monitoring System data, this study examined the weighted annual seasonal influenza vaccination rates and the relationship of various factors to vaccination among NM residents with a live birth during those years.

Results:

Among respondents, 53.8% were Hispanic, 15.7% were Native American, and 30.5% were non-Hispanic White. The vaccination rate in NM increased from 49.0% in 2012 to 64.8% in 2014. The adjusted odds of vaccination were higher among women whose health care provider recommended/offered vaccination during the year prior to delivery compared to women whose provider did not (AOR = 11.92, 95% confidence interval [CI: 9.86, 14.42]) and among those living in the U.S.–Mexico nonborder counties compared to those living in the border counties (AOR = 1.23, 95% CI [1.18, 1.25]).

Conclusion:

Efforts to increase the vaccination rate among pregnant women in border states should concentrate on health care providers and the highest risk women, such as those resident in the border region.

Determinants of influenza vaccination uptake in pregnancy: a large single-Centre cohort study

BACKGROUND

Although vaccination of pregnant women against influenza is recommended, the vaccination rate remains low. We conducted a study to identify determinants of influenza vaccination uptake in pregnancy in order to identify strategies to improve seasonal influenza vaccination rates.

METHODS

Prospective observational hospital-based study in the French hospital performing the highest number of deliveries, located in the city of Lille, among all women who had given birth during the 2014-2015 influenza season. Data were collected through a self-completed questionnaire and from medical files. The vaccination uptake was self-reported. Determinants of vaccination uptake were identified using logistic regression analysis.

RESULTS

Of the 2045 women included in the study, 35.5% reported that they had been vaccinated against influenza during their pregnancy. The principal factors significantly associated with greater vaccination uptake were previous influenza vaccination (50.9% vs 20.2%, OR 4.1, 95% CI 3.1-5.5), nulliparity (41.0% vs 31.3%, OR 2.5, 95% CI 1.7-3.7), history of preterm delivery < 34 weeks (43.4% vs 30.3%, OR 2.3, 95% CI 1.1-4.9), the mother's perception that the frequency of vaccine complications for babies is very low (54.6% vs 20.6%, OR 1.1, 95% CI 0.5-2.2), the mother's good knowledge of influenza and its vaccine (61.7% vs 24.4%, OR 3.1, 95% CI 2.2-4.4), hospital-based prenatal care in their first trimester of pregnancy (55.0% vs 30.2%, OR 2.1, 95% CI 1.2-3.7), vaccination recommendations during pregnancy by a healthcare worker (47.0% vs 2.7%, OR 18.8, 95% CI 10.0-35.8), receipt of a vaccine reimbursement form (52.4% vs 18.6%, OR 2.0, 95% CI 1.5-2.7), and information from at least one healthcare worker about the vaccine (43.8% vs 19.1%, OR 1.8, 95% CI 1.3-2.6).

CONCLUSIONS

Our findings suggest that in order to increase flu vaccination compliance among pregnant women, future public health programmes must ensure cost-free access to vaccination, and incorporate education about the risks of influenza and the efficacy/safety of vaccination and clear recommendations from healthcare professionals into routine antenatal care.

Vaccination against influenza among pregnant women in southern Brazil and associated factors

Abstract This article aims to identify the prevalence and factors associated with influenza vaccination in pregnant women. This is a cross-sectional study conducted in a municipality in the southernmost region of Brazil, which included all women giving birth in 2016. The outcome was having received the vaccine against influenza during pregnancy. Sociodemographic, behavioral and prenatal care characteristics and morbidities were analyzed. The analysis included sample description, the prevalence of vaccination for each independent variable and a multivariate analysis. Two thousand six hundred ninety-four pregnant women were interviewed, of which 53.9% reported having been vaccinated. Factors associated with increased prevalence of vaccination were mother’s higher schooling, prenatal care, tetanus vaccination and prenatal care performed in a public service. On the other hand, prenatal care onset after the first quarter reduced the prevalence of vaccination. The results point to the need to reinforce the importance of vaccination against influenza among pregnant women and among health professionals, regardless of the severity of the current epidemiological setting.

The fetal origins of mental illness

The impact of infections and inflammation during pregnancy on the developing fetal brain remains incompletely defined, with important clinical and research gaps. Although the classic infectious TORCH pathogens (ie, Toxoplasma gondii, rubella virus, cytomegalovirus [CMV], herpes simplex virus) are known to be directly teratogenic, emerging evidence suggests that these infections represent the most extreme end of a much larger spectrum of injury. We present the accumulating evidence that prenatal exposure to a wide variety of viral and bacterial infections-or simply inflammation-may subtly alter fetal brain development, leading to neuropsychiatric consequences for the child later in life. The link between influenza infections in pregnant women and an increased risk for development of schizophrenia in their children was first described more than 30 years ago. Since then, evidence suggests that a range of infections during pregnancy may also increase risk for autism spectrum disorder and depression in the child. Subsequent studies in animal models demonstrated that both pregnancy infections and inflammation can result in direct injury to neurons and neural progenitor cells or indirect injury through activation of microglia and astrocytes, which can trigger cytokine production and oxidative stress. Infectious exposures can also alter placental serotonin production, which can perturb neurotransmitter signaling in the developing brain. Clinically, detection of these subtle injuries to the fetal brain is difficult. As the neuropsychiatric impact of perinatal infections or inflammation may not be known for decades after birth, our construct for defining teratogenic infections in pregnancy (eg, TORCH) based on congenital anomalies is insufficient to capture the full adverse impact on the child. We discuss the clinical implications of this body of evidence and how we might place greater emphasis on prevention of prenatal infections. For example, increasing uptake of the seasonal influenza vaccine is a key strategy to reduce perinatal infections and the risk for fetal brain injury. An important research gap exists in understanding how antibiotic therapy during pregnancy affects the fetal inflammatory load and how to avoid inflammation-mediated injury to the fetal brain. In summary, we discuss the current evidence and mechanisms linking infections and inflammation with the increased lifelong risk of neuropsychiatric disorders in the child, and how we might improve prenatal care to protect the fetal brain.

Analyzing the Urban-Rural Vaccination Coverage Disparity through a Fair Decomposition in Zhejiang Province, China

Objectives: Exploring determinants underlying disparities in full vaccination coverage (FVC) can contribute to improved immunization interventions. FVC and its risk factors in Zhejiang province have been studied, yet the determinants explaining the rural-urban disparity in FVC have not been studied. This study aimed to disentangle the factors explaining rural-urban disparities in FVC of vaccine doses scheduled during the first year of life in Zhejiang province. Methods: We used data from a vaccination coverage survey among children aged 24-35 months conducted in 2016. The outcome measure was full vaccination status, and the grouping variable was the area of residence. Descriptive statistics were used to analyze the FVC and rural-urban residence across the exposure variables. The Fairlie decomposition technique was used to decompose factors contributing to explaining the FVC disparity. Results: There were 847 children included in this study, of which 49.6% lived in a rural area. FVC was 94% in rural areas and 85% in urban areas. A disparity of 9% to the advantage of the rural areas and the exposure variables explained 81.1% of the disparity. Maternal factors explained 49.7% of the explained disparity with education, occupation, and ethnicity being the significant contributors to the explained disparity. Children's birth order and immigration status contributed somewhat to the explained inequality. Conclusion: There was a significant disparity in FVC in Zhejiang province, a disadvantage to the urban areas. Policy recommendations or health interventions to reduce the inequality should be focused on eliminating poverty and women's illiteracy, targeted at migrant children or children from minority ethnicities.

Seasonal influenza vaccine uptake and vaccine refusal among pregnant women in France: results from a national survey

Pregnant women and infants are at high risk for severe influenza and many countries, including France, recommend annual influenza immunization during pregnancy. We aimed to estimate influenza vaccination and refusal rates and assess associated factors among pregnant women during the 2015-16 season in France. We used data from a national representative sample of women who gave birth in March 2016 and were interviewed before hospital discharge (N = 11,752). In the multivariable analysis, robust Poisson regression models were used to study associations with maternal characteristics and prenatal care characteristics. Influenza vaccine coverage among pregnant women was 7.4% (95% confidence interval [CI]: 6.9-7.9). Only 24.9% (95% CI: 24.2-25.7) of women said that they received a care provider proposal for vaccination and 70.4% (95% CI: 68.7-72.0) of these declined it. Vaccine uptake was associated with low parity (prevalence ratio [PR] = 2.1; 95% CI: 1.4-3.2 for parity 0 vs ≥ 3), high educational level (PR = 2.5; 95% CI: 2.0-3.2), healthcare occupation during pregnancy (PR = 1.8; 95% CI: 1.5-2.1) and preexisting conditions at risk for influenza (PR = 1.7; 95% CI: 1.3-2.2). Women were more frequently vaccinated when their main care provider was a general practitioner. Multiparae women and those with medium or low educational level were significantly more likely than others to decline influenza vaccine after a provider proposal. Influenza vaccine coverage is very low in France, mainly because of infrequent care provider proposals and also frequent women's refusals. Effective interventions should be designed to promote vaccination among medical professionals and reduce vaccine hesitancy among pregnant women.

Inequalities in maternal pertussis vaccination uptake: a cross-sectional survey of maternity units

Background

This study aims to estimate pertussis vaccine uptake in pregnant women in England, describe timing of vaccine delivery and examine variations in uptake.

Methods

Cross-sectional survey of vaccine uptake in women delivering in maternity units in England. Variation in uptake described according to geography, maternal age, ethnicity and parity as reported by the midwife completing the survey.

Results

A total of 1325 surveys were returned, 85% of which (1128) contained information about vaccination. Vaccine uptake was 61.8% (95% CI: 56.8-66.5) and was higher in the White British ethnic group than any other (67.7%, 95% CI: 63.5 to 71.5). Uptake was higher outside London (65.3%, 95% CI: 61.1-69.3) than within London (31.0%, 95% CI: 24.9-38.0). Reported uptake was lower in areas of high deprivation, and in women of higher parity, observations that were not statistically significant in the multivariable model. Overall, 74% of women were vaccinated between 28 and 32 weeks.

Conclusions

Pertussis vaccine uptake in pregnant women varies significantly across the country and is affected by ethnicity, deprivation and parity. Variations should be addressed through service delivery models designed to reduce potential inequalities in infant protection.

Predictors for influenza vaccination among Thai pregnant woman: The role of physicians in increasing vaccine uptake

BACKGROUND

Physician recommendation and attitudes and beliefs of pregnant women toward influenza and vaccination may influence vaccine uptake during pregnancy. We examined how physician recommendation and health beliefs of pregnant women may jointly affect influenza vaccination during pregnancy.

METHODS

Thai pregnant women aged ≥18 years and >13 gestational weeks attending antenatal care (ANC) clinics, and ANC physicians were recruited during May-August 2015. Women and physicians, linked using unique identifiers, provided data on demographic, health and work history, knowledge, attitudes, and beliefs toward influenza and vaccination, based on Health Belief Model constructs. Physicians also provided data on their practices in recommending influenza vaccination during pregnancy. Prevalence ratios for the association between knowledge, attitudes and beliefs of pregnant women, physician recommendation and documented receipt of vaccination within 30 days of the visit were calculated.

RESULTS

Among 610 women, the median age was 27 years; 266 (44%) and 344 (56%) were in the second and third trimesters, respectively. Twenty-one (3%) had pre-existing conditions. Of 60 physicians with the median years of practice of 5; 17 (28%) reported frequently/usually/always recommending influenza vaccine to their pregnant patients, while 43 (72%) reported never/rarely/sometimes recommending the vaccine. Controlling for the pregnant women's knowledge and beliefs, pregnant women whose physician recommended influenza vaccination were 2.3 times (95% confidence interval 1.4-3.8) more likely to get vaccinated.

CONCLUSIONS

In this study, physician recommendation was the only significant factor associated with influenza vaccine uptake among Thai pregnant women. Understanding physicians' motivation/barrier to recommending influenza vaccination to pregnant women may increase coverage.

Immunogenicity and safety of a quadrivalent inactivated influenza vaccine in pregnant women: a randomized, observer-blind trial

Vaccination against influenza during pregnancy provides direct protection to pregnant women and indirect protection to their infants. Trivalent inactivated influenza vaccines (IIV3s) are safe and effective during pregnancy, but quadrivalent inactivated influenza vaccines (IIV4s) have not been evaluated in pregnant women and their infants. Here, we report the results of a randomized phase IV study to evaluate the immunogenicity and safety of IIV4 vs. IIV3 in pregnant women. Participants aged ≥18 years at weeks 20 to 32 of gestation were randomly assigned in a 2:1 ratio to receive a single dose of IIV4 (n = 230) or IIV3 (n = 116). Between baseline and 21 days after vaccination, hemagglutination inhibition (HAI) antibody titers increased in both groups by similar magnitudes for the two influenza A strains and single B strain common to IIV4 and IIV3. For the additional B strain in IIV4, HAI titers were higher in IIV4 recipients than IIV3 recipients (post-/pre-vaccination geometric mean titer ratio, 6.3 [95% CI: 5.1 − 7.7] vs. 3.4 [95% CI: 2.7 − 4.3]). At delivery, in both groups, HAI antibody titers for all strains were 1.5 − 1.9-fold higher in umbilical cord blood than in maternal blood, confirming active transplacental antibody transfer. Rates of solicited and unsolicited vaccine-related adverse events in mothers were similar between the two groups. Live births were reported for all participants and there were no vaccine-related adverse events in newborns. These results suggest IIV4 is as safe and immunogenic as IIV3 in pregnant women, and that maternal immunization with IIV4 should protect newborns against influenza via passively acquired antibodies.

Seasonal Influenza Vaccination Coverage Trends Among Adult Populations, U.S., 2010-2016

INTRODUCTION

Influenza is a major cause of morbidity and mortality among adults. The most effective strategy for preventing influenza is annual vaccination. However, vaccination coverage has been suboptimal among adult populations. The purpose of this study is to assess trends in influenza vaccination among adult populations.

METHODS

Data from the 2010-2016 National Health Interview Survey were analyzed in 2018 to estimate vaccination coverage during the 2010-2011 through 2015-2016 seasons. Trends of vaccination in recent years were assessed. Vaccination coverage by race/ethnicity within each group was examined. Multivariable logistic regression and predictive marginal models were conducted to identify factors associated with vaccination, and interactions between race/ethnicity and other demographic and access-to-care characteristics were assessed.

RESULTS

Vaccination coverage among adults aged ≥18 years increased from 38.3% in the 2010-2011 season to 43.4% in the 2015-2016 season, with an average increase of 1.3 percentage points annually. From the 2010-2011 through 2015-2016 seasons, coverage was stable for adults aged ≥65 years and changed by -0.1 to 9.9 percentage points for all other examined subgroups. Coverage in 2015-2016 was 70.4% for adults aged ≥65 years, 46.4% for those aged 50-64 years, and 32.3% for those aged 18-49 years; 47.9% for people aged 18-64 years with high-risk conditions; 64.8% for healthcare personnel; and 50.3% for pregnant women. Among adults aged ≥18 years for the 2015-2016 season, coverage was significantly lower among non-Hispanic blacks and Hispanics compared with non-Hispanic whites.

CONCLUSIONS

Overall, influenza vaccination coverage among adults aged ≥18 years increased during 2010-2016, but it remained below the national target of 70%. Vaccination coverage varied by age, risk status, race/ethnicity, healthcare personnel, and pregnancy status. Targeted efforts are needed to improve coverage and reduce disparities.

Knowledge and Attitudes about the Flu Vaccine among Pregnant Women in the Valencian Community (Spain)

Background and Objectives: To describe the knowledge and attitudes related to the acceptance of the flu vaccine during pregnancy in women, from two Health Departments of the Valencian Community (VC), during the 2015–2016 season, after receiving prenatal care. Materials and Methods: A prospective observational study was conducted during the annual vaccine season of women ascribed to prenatal care. A midwife offered flu vaccine advice and afterwards conducted a telephone poll of a representative sample, in order to find out the reason for accepting or rejecting the vaccine. Results: Of the 1017 expectant women who received advice about the vaccine, 77.4% (95% CI: 74.8–79.9%) declared their intention to vaccinate. After the recommendation, the vaccine coverage was 61.6%, with a percentage of accordance of 98.8% (95% CI: 98.0–99.6%) between the coverage declared and the Nominal Vaccination Registry (NVR) of the VC. Additionally, 67.2% of the expectant women were interviewed (n = 683). Most were aware of the recommendation and identified the health center and the midwife as the main sources of information. The internet was a consistent source in favor of vaccination 80.8% (n = 42). The obstetric variables (risk during the pregnancy, end of pregnancy, and feeding the newborn) did not have a statistically significant relationship with the vaccination. The women declared a high adherence to the vaccinations present in the child vaccination calendar, but rejected (31.3%) the flu vaccine, as they had not received it previously and did not want it because of their expectant state. Conclusions: The women positively evaluated the effectiveness and safety of the vaccines. However, with the flu vaccine, “not being previously vaccinated” and the “doubts about its safety” represented more than half of the reasons put forth for its rejection. Ensuring that the flu vaccine is perceived as more effective and acceptable through the messages directed towards the expectant mothers, directly through the midwives or through the communication media and social networks, will result in an increase of vaccine coverage.

Does the availability of influenza vaccine at prenatal care visits and of immediate vaccination improve vaccination coverage of pregnant women?

Introduction

Although vaccination against influenza is recommended for pregnant women in France because it exposes them to a risk of death and severe respiratory complications, their vaccination coverage in 2016 was estimated at 7%. This study's principal objective was to assess the association between the availability of influenza vaccination at prenatal care visits and vaccination coverage.

Material and methods

This multicenter survey took place in 3 Paris-area public hospital (AP-HP) maternity wards (A, B, and C). Only maternity ward A offered the vaccine and vaccination without charge at prenatal visits. Data were collected from parturients during 10 days in January 2017 by a self-administered anonymous questionnaire.

Results

Data from 248 women showed overall vaccination coverage of 19.4% (48/248): 35.4% (46/130) in maternity unit A, 2.7% (2/75) in B, and 0% (0/43) in C (P<0.01). After adjustment for socio-demographic characteristics, women at maternity ward A were significantly more likely to be vaccinated than those at B and C (aOR 25.52, 95%CI [5.76–113.10]). Other factors significantly associated with higher vaccination coverage were the mother’s French birth (aOR 2.37 CI [1.03–5.46]) and previous influenza vaccination (aOR 3.13, 95%CI [1.25–7.86]). Vaccinated women generally considered they had received adequate information (aOR 4.15 CI [2.10–8.22]), principally from the professional providing their prenatal care. Nonvaccination was attributed to the absence of an offer of vaccination (81.5%), fear of fetal side effects (59.5%), and inadequate information (51.4%).

Conclusion

Our results show that availability of influenza vaccination, free of charge, at prenatal consultations at the maternity ward increases vaccination coverage significantly.

Health outcomes of young children born to mothers who received 2009 pandemic H1N1 influenza vaccination during pregnancy: retrospective cohort study

OBJECTIVE

To determine whether any association exists between exposure to 2009 pandemic H1N1 (pH1N1) influenza vaccination during pregnancy and negative health outcomes in early childhood.

DESIGN

Retrospective cohort study.

SETTING

Population based birth registry linked with health administrative databases in the province of Ontario, Canada.

PARTICIPANTS

All live births from November 2009 through October 2010 (n=104 249) were included, and children were followed until 5 years of age to ascertain study outcomes.

MAIN OUTCOME MEASURES

Rates of immune related (infectious diseases, asthma), non-immune related (neoplasms, sensory disorders), and non-specific morbidity outcomes (urgent or inpatient health services use, pediatric complex chronic conditions) were evaluated from birth to 5 years of age; under-5 childhood mortality was also assessed. Propensity score weighting was used to adjust hazard ratios, incidence rate ratios, and risk ratios for potential confounding.

RESULTS

Of 104 249 live births, 31 295 (30%) were exposed to pH1N1 influenza vaccination in utero. No significant associations were found with upper or lower respiratory infections, otitis media, any infectious diseases, neoplasms, sensory disorders, urgent and inpatient health services use, pediatric complex chronic conditions, or mortality. A weak association was observed between prenatal pH1N1 vaccination and increased risk of asthma (adjusted hazard ratio 1.05, 95% confidence interval 1.02 to 1.09) and decreased rates of gastrointestinal infections (adjusted incidence rate ratio 0.94, 0.91 to 0.98). These results were unchanged in sensitivity analyses accounting for any potential differential healthcare seeking behavior or access between exposure groups.

CONCLUSIONS

No associations were observed between exposure to pH1N1 influenza vaccine during pregnancy and most five year pediatric health outcomes. Residual confounding may explain the small associations observed with increased asthma and reduced gastrointestinal infections. These outcomes should be assessed in future studies.

Coverage and determinants of influenza vaccine among pregnant women: a cross-sectional study

BACKGROUND

Pregnant women are at increased risk of influenza-related complications. The World Health Organisation recommends influenza vaccination to this high-risk population as highest priority. However, achieving high influenza vaccine coverage among pregnant women remains challenging. We conducted a cross-sectional survey to estimate the coverage and determinants of influenza vaccination among pregnant women in Singapore.

METHODS

Between September and November 2017, pregnant women aged ≥21 years were recruited at two public hospitals in Singapore. Participants completed an anonymous, self-administered online questionnaire assessing participants' influenza vaccination uptake, knowledge of and attitudes towards influenza and the influenza vaccine, vaccination history, willingness to pay for the influenza vaccine, and external cues to vaccination. We estimated vaccine coverage and used multivariable Poisson models to identify factors associated with vaccine uptake.

RESULTS

Response rate was 61% (500/814). Only 49 women (9.8, 95% Confidence Interval (CI): 7.3-12.7%) reported receiving the vaccine during their current pregnancy. A few misconceptions were identified among participants, such as the belief that influenza can be treated with antibiotics. The most frequent reason for not being vaccinated was lack of recommendation. Women who were personally advised to get vaccinated against influenza during pregnancy were 7 times more likely to be vaccinated (prevalence ratio (PR) = 7.11; 95% CI: 3.92-12.90). However, only 12% of women were personally advised to get vaccinated. Other factors associated with vaccine uptake were vaccination during a previous pregnancy (PR = 2.51; 95% CI: 1.54-4.11), having insurance to cover the cost of the vaccine (PR = 2.32; 95% CI: 1.43-3.76), and higher vaccine confidence (PR = 1.62; 95% CI: 1.30-2.01).

CONCLUSIONS

Influenza vaccination uptake among pregnant women in Singapore is low. There is considerable scope for improving vaccination coverage in this high-risk population through vaccination recommendations from healthcare professionals, and public communication targeting common misconceptions about influenza and influenza vaccines.

'Links2HealthierBubs' cohort study: protocol for a record linkage study on the safety, uptake and effectiveness of influenza and pertussis vaccines among pregnant Australian women

INTRODUCTION

Pregnant women and infants are at risk of severe influenza and pertussis infection. Inactivated influenza vaccine (IIV) and diphtheria-tetanus-acellular pertussis vaccine (dTpa) are recommended during pregnancy to protect both mothers and infants. In Australia, uptake is not routinely monitored but coverage appears sub-optimal. Evidence on the safety of combined antenatal IIV and dTpa is fragmented or deficient, and there remain knowledge gaps of population-level vaccine effectiveness. We aim to establish a large, population-based, multi-jurisdictional cohort of mother-infant pairs to measure the uptake, safety and effectiveness of antenatal IIV and dTpa vaccines in three Australian jurisdictions. This is a first step toward assessing the impact of antenatal vaccination programmes in Australia, which can then inform government policy with respect to future strategies in national vaccination programmes. METHODS AND ANALYSIS: 'Links2HealthierBubs' is an observational, population-based, retrospective cohort study established through probabilistic record linkage of administrative health data. The cohort includes births between 2012 and 2017 (~607 605 mother-infant pairs) in jurisdictions with population-level antenatal vaccination and health outcome data (Western Australia, Queensland and the Northern Territory). Perinatal data will be the reference frame to identify the cohort. Jurisdictional vaccination registers will identify antenatal vaccination status and the gestational timing of vaccination. Information on maternal, fetal and child health outcomes will be obtained from hospitalisation and emergency department records, notifiable diseases databases, developmental anomalies databases, birth and mortality registers.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Western Australian Department of Health, Curtin University, the Menzies School of Health Research, the Royal Brisbane and Women's Hospital, and the West Australian Aboriginal Health Ethics Committees. Research findings will be disseminated in peer-reviewed journals, at scientific meetings, and may be incorporated into communication materials for public health agencies and the public.

Potential use of Western Australia’s mandatory Midwives Notification System for routinely monitoring antenatal vaccine coverage

Background Despite the maternal and infant health benefits of antenatal vaccines and availability of government-funded vaccination programs, Australia does not have a national system for routinely monitoring antenatal vaccination coverage. We evaluated the potential use of Western Australia’s mandatory Midwives Notification System (MNS) as a tool for routinely monitoring antenatal vaccination coverage. Methods Two hundred and sixty-eight women who gave birth to a live infant between August and October 2016 participated in a telephone survey of vaccines received in their most recent pregnancy. For women who reported receiving influenza and/or pertussis vaccine and whose vaccination status was documented by their vaccine provider, MNS vaccination data were compared with the vaccine provider’s record as the ‘gold standard.’ For women who reported receiving no vaccines, MNS vaccination data were compared with self-reported information. Results Influenza and pertussis vaccination status was complete (i.e. documented as either vaccinated or not vaccinated) for 66% and 63% of women, respectively. Sensitivity of MNS influenza vaccination data was 65.7% (95% CI 56.0-74.2%) and specificity was 53.0% (95% CI 42.4-63.4%). Sensitivity of MNS pertussis vaccination data was 62.5% (95% CI 53.3-70.9%) and specificity was 40.4% (95% CI 27.6-54.7%). There was no difference between vaccinated and unvaccinated women in the proportion of MNS records with missing or unknown vaccination information. When considering only MNS records with complete vaccination information, the sensitivity of the MNS influenza vaccination field was 91.8% (95% CI 83.0-96.9%) and the sensitivity of the MNS pertussis vaccination field was 88.0% (95% CI 76.7-95.5%). Conclusion Due to the high proportion of records with missing or unknown vaccination status, we observed low sensitivity and specificity of antenatal vaccination data in the MNS. However, given we did not observe differential ascertainment by vaccination status, MNS records with complete information may be reliable data source for routinely monitoring antenatal vaccine coverage.

Low awareness of influenza vaccination among pregnant women and their obstetricians: a population-based survey in Beijing, China

We assessed how an awareness of influenza vaccination might influence both the willingness of pregnant women to be vaccinated and the readiness of obstetricians to recommend antenatal influenza vaccination in Beijing, China. From March to April 2016, we surveyed pregnant women who were attending antenatal clinics at eight hospitals in Beijing, along with obstetricians at the same clinics. Demographic, attitudinal, and behavioral information regarding influenza vaccination were collected using structured questionnaires. Consent and completed questionnaires were obtained from 988 of 1009 pregnant women and 165 of 173 obstetricians. Only 113 (11.4%) pregnant women reported being willing to receive an influenza vaccine during their pregnancies. Willingness to receive an influenza vaccination was positively associated with ever having a history of vaccination or influenza (aOR=6.74, 95%CI: 1.72-26.4, P=0.006), perceiving benefits of vaccination (aOR=1.67, 95%CI: 1.00-2.79, P=0.050), and having a higher level of influenza knowledge (aOR=82.2, 95%CI: 21.7-311.1, P<0.001). Among obstetricians, only 19.4% reported being willing to recommend influenza vaccination to their pregnant patients and 15.2% reported knowledge that influenza vaccination during pregnancy was recommended by China's National Health Commission. Neither pregnant women nor their obstetricians were aware of Chinese government recommendations that antenatal influenza vaccination should be encouraged and provided. Pregnant women and their obstetricians were ill-informed of the relevant evidence. It is in emergent need to train and disseminate the updated evidence on influenza vaccination to obstetricians. It also warranted more high-quality trials regarding influenza vaccination during pregnancy to address public concern.

Small interface changes have dramatic impacts: how mandatory fields in electronic medical records increased pertussis vaccination rates in Australian obstetric patients

Introduction

Electronic health records have been widely introduced into clinical practice. The aim of this study was to determine whether a small interface change could improve compliance with a key quality indicator, namely antenatal pertussis vaccination.

Methods

Audits were performed between 1–31 July 2015 and 1–31 July 2017 of all deliveries at the Centenary Hospital for Women and Children to determine compliance with antenatal pertussis vaccination. The single difference between time points was changing the interface so the antenatal pertussis vaccination field became compulsory.

Results

275 and 299 women delivered in the audit periods. Vaccination rates almost doubled (52.7% vs 91.4%, p<0.0001).

Conclusion

Small interface changes increase compliance. Interface change could be considered for key quality outcomes in patient care.

Influenza Vaccination Coverage Among Pregnant Women in the U.S., 2012-2015

INTRODUCTION

Pregnant women are at increased risk for severe illness from influenza and influenza-related complications. Vaccinating pregnant women is the primary strategy to protect them and their infants from influenza. This study aims to assess influenza vaccination coverage during three influenza seasons (2012-2015) from a national probability-based sampling survey and evaluate potential factors that influence vaccination uptake among pregnant women.

METHODS

Data from the 2012 through 2015 National Health Interview Surveys were analyzed in 2017. Pregnant women aged 18-49 years were included in the analysis. The Kaplan-Meier survival analysis procedure was used for vaccination coverage in each season. Bivariate and multivariable logistic regression analyses were performed to examine factors associated with vaccination. Adjusted vaccination coverage and adjusted prevalence ratios are reported with corresponding 95% CIs.

RESULTS

In the 2012-2013, 2013-2014, and 2014-2015 influenza seasons, 40.4%, 45.4%, and 43.1% of pregnant women were vaccinated, respectively. Multivariable analysis indicated that factors independently associated with a lower likelihood of vaccination included having only a high school education, having three or less provider visits, and having no usual place of care (p<0.05). Less than half of women with ten or more visits were vaccinated (48.6%).

CONCLUSIONS

Vaccination coverage among pregnant women from this nationally representative sample was suboptimal during recent influenza seasons. Vaccination coverage was lower among certain sociodemographic, access-to-care subgroups. Multifactorial vaccination barriers may exist. Interventions, such as assessing vaccination history at every visit and implementing reminder-recall systems, standing orders, and addressing vaccination hesitancy, are needed to increase vaccination uptake among pregnant women.

Prenatal vaccination of mothers and hepatitis B vaccination of their infants

Tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and influenza vaccination are recommended during pregnancy primarily to prevent influenza and pertussis in mothers and their infants. This study examines associations between prenatal Tdap vaccination and influenza vaccination of mothers and hepatitis B vaccination of their infants. A retrospective cohort study was conducted using data from electronic medical records from 15,468 deliveries to 14,925 mothers occurring April 2, 2014-December 3, 2016 at a university hospital in Texas. Hepatitis B vaccine receipt in the first 3 days of life was dichotomized. Margins post-estimation commands in Stata SE 15.1 were used to obtain predicted probabilities and risk differences after estimating odds ratios in logistic regression with robust variance estimates. Adjusted models included maternal age, race/ethnicity, Medicaid use, year of delivery, parity, and gravidity. Infants of mothers who received prenatal influenza vaccination in the 2014-2015 and 2015-2016 influenza seasons were more likely than those of mothers who did not to receive a hepatitis B vaccine in their first 3 days of life (adjusted risk difference (RD) 2.8%, 95% confidence interval (CI) 1.5-4.1% and RD 2.2%, 95% CI 0.9-3.5%, respectively). Hepatitis B vaccination was also higher among infants of Tdap-eligible mothers who received prenatal Tdap vaccination during pregnancy compared to those of mothers who did not (adjusted RD 9.1%, 95% CI 7.6-10.5%). Overall, prenatal vaccination was significantly associated with uptake of infant hepatitis B vaccine.

Maternal Care Providers' Barriers Regarding Influenza and Pertussis Vaccination During Pregnancy in Catalonia, Spain

Objective Maternal care providers (MCPs), obstetrician-gynaecologists and midwives are uniquely placed to increase maternal vaccination acceptance. We aimed to assess their knowledge, attitudes and practices regarding influenza and pertussis vaccination during pregnancy. Methods We conducted an online survey among MCPs working at "Attention to Sexual and Reproductive Health" (ASSIR) Units in Catalonia region. The survey included questions about current recommendations of influenza and pertussis immunization during pregnancy, reasons for not routinely recommending vaccination and several strategies to increase vaccination uptake. Results A total of 194 MCPs completed the survey, 178 (91.8%) were female and 145 (70%) were midwives. Only 61 (31.4%) stated they vaccinated themselves annually against influenza with a significant lower uptake among midwives (26.9%) than obstetrician-gynaecologists (44.9%) (p = 0.03). Overall, 53.6% of MCPs knew influenza vaccine was indicated during first trimester but only 43.3% stated they prescribed it. Almost all MCPs (98.5%) knew pertussis vaccine was recommended and 97.4% stated they prescribed it. The most important vaccination barrier found was the concern related to vaccine adverse events (25.9%) and more midwives than obstetrician-gynaecologists expressed this concern (30.8 vs. 10%) (p = 0.02). The most popular strategies were: including vaccine recommendations in the pregnancy booklet (93.8%) and receiving vaccination training (92.3%). In the adjusted analysis, the only factor significantly associated with MCPs' prescription of influenza vaccine during second/third trimester was having been vaccinated themselves (odds ratio 3.70, 95% confidence interval 1.3-13.2). Conclusions for Practice Implementation of practical tools, continuous training and clear definition of responsibilities regarding vaccination among MCPs may have a significant impact on maternal vaccination coverage.

Influenza vaccination of pregnant women: Engaging clinicians to reduce missed opportunities for vaccination

BACKGROUND

Antenatal influenza vaccination (AIV) is an effective intervention for protecting pregnant women and their newborns against influenza. Although the World Health Organization recommends AIV at any stage of pregnancy, in low- and middle-income countries, including India, it is rarely provided. Research suggests that antenatal care (ANC) provider practices explain much of this limited coverage. Our study in urban Pune, India, assessed the feasibility of a two-stage clinician-engagement strategy to reduce missed opportunities for AIV in urban private-practice ANC clinics.

METHODS

Clinicians were randomized to intervention and control groups in slum and middle-class study sites. Intervention-group clinicians (active clinicians) were assessed on vaccination-related views and practices, and were presented with authoritative AIV recommendations from global, academic and professional medical organizations. In a second meeting after a community survey, findings concerning vaccination-related views and experiences were explained to active clinicians. Assessments of community vaccination views were not provided to control-group clinicians. Both groups maintained logs of ANC clinic visit vaccination status throughout the 11-month study period to enable identification of missed and taken opportunities for vaccination. Analyses were restricted to visits of women in their third trimester without previous AIV in the current pregnancy.

RESULTS

Overall, 30 clinicians participated. After first and second interactions, active clinicians in middle-class communities vaccinated at 12.2% and 37.8%, respectively. Middle-class control clinicians vaccinated at <0.2% throughout the study. This difference in AIV taken opportunities between middle-class active and control clinics was statistically significant (p < 0.05) after first and second interactions. In slum-community sites, active clinicians' AIV activity was minimal throughout.

CONCLUSIONS

Our approach for engaging clinicians effectively reduced missed opportunities for AIV in urban middle-class settings of Pune. It may also improve maternal vaccination for other conditions. The absence of any similar effect in slum-based clinics likely reflects critical limitations of vaccine access.

Trends in Tdap vaccination among privately insured pregnant women in the United States, 2009-2016

BACKGROUND

Infants younger than 6 months are at increased risk of complications and mortality from pertussis infection. In October 2012, the Advisory Committee on Immunization Practices revised its recommendation to include a Tdap dose during each pregnancy, ideally between 27 and 36 weeks gestation.

OBJECTIVE

Assess trends in Tdap vaccination coverage among privately insured pregnant women from 2009 to 2016 including timing of Tdap vaccination (before, during, or after pregnancy), trimester of vaccination for women vaccinated during pregnancy, and missed vaccination opportunities for unvaccinated women. Identify factors associated with vaccination during the optimal period of 27-36 weeks gestation.

STUDY DESIGN

Retrospective analysis of privately insured women 15-49 years who delivered live births during 2009-2016 conducted using 2009-2016 MarketScan data. Tdap vaccination coverage and the timing of Tdap vaccine administration were assessed for women continuously enrolled from 6 months before pregnancy to 1 month after delivery. Multivariable logistic regression was performed to identify factors independently associated with receipt of Tdap vaccine at 27-36 weeks gestation.

RESULTS

Tdap vaccination coverage during pregnancy increased from 0.4% in 2009 to 6.2% in 2012 and to 53.2% in 2016. The proportion of vaccinated women receiving Tdap at 27-36 weeks gestation increased from <10% in 2009 to nearly 90% in 2016, with most vaccination occurring at 27-32 weeks gestation. Women of older age, residing in a metropolitan statistical area, residing outside the South, and having a capitated health insurance plan were more likely to receive Tdap at 27-36 weeks gestation than their counterparts. Among women not vaccinated during pregnancy, 77.7% had a pregnancy-related medical claim between 27 and 36 weeks gestation.

CONCLUSION

Tdap vaccination coverage during pregnancy increased significantly from 2009 to 2016, with the greatest increase occurring after the revised Advisory Committee on Immunization Practices recommendation. Most women who did not receive Tdap vaccine had a missed vaccination opportunity during pregnancy, indicating potential for much higher vaccination coverage and consequent infant protection against pertussis.

Epidemiology of influenza in pregnant women hospitalized with respiratory illness in Moscow, 2012/2013-2015/2016: a hospital-based active surveillance study

Background

To better understand the impact of seasonal influenza in pregnant women we analyzed data collected during four seasons at a hospital for acute respiratory infection that specializes in treating pregnant women.

Methods

This was a single-center active surveillance study of women 15–44 years of age hospitalized for acute respiratory diseases between 2012/2013 and 2015/2016 in Moscow, Russian Federation. Women had to have been hospitalized within 7 days of the onset of symptoms. Swabs were taken within 48 h of admission, and influenza was detected by reverse transcription-polymerase chain reaction.

Results

During the four seasons, of the 1992 hospitalized women 1748 were pregnant. Laboratory-confirmed influenza was detected more frequently in pregnant women (825/1748; 47.2%) than non-pregnant women (58/244; 23.8%) (OR for influenza = 2.87 [95% CI, 2.10–3.92]; p <  0.001). This pattern was homogenous across seasons (p = 0.112 by test of homogeneity of equal odds). Influenza A(H1N1)pdm09 was the dominant strain in 2012/2013, A(H3N2) in 2013/2014, B/Yamagata lineage and A(H3N2) in 2014/2015, and A(H1N1)pdm09 in 2015/2016. Influenza-positive pregnant admissions went to the hospital sooner than influenza-negative pregnant admissions (p <  0.001). The risk of influenza increased by 2% with each year of age and was higher in women with underlying conditions (OR = 1.52 [95% CI, 1.16 to 1.99]). Pregnant women positive for influenza were homogeneously distributed by trimester (p = 0.37 for homogeneity; p = 0.49 for trend). Frequencies of stillbirth, delivery, preterm delivery, and caesarean delivery did not significantly differ between influenza-positive and influenza-negative hospitalized pregnant women or between subtypes/lineages.

Conclusions

Pregnant women are at increased risk for hospitalization due to influenza irrespective of season, circulating viruses, or trimester.

Electronic supplementary material

The online version of this article (10.1186/s12884-019-2192-z) contains supplementary material, which is available to authorized users.

Adherence and Concordance of Influenza and Pertussis Vaccination Coverage in Pregnant Women in Spain

Background: Pregnant women should receive two vaccines during pregnancy due to maternal-foetal complications and risks as well as the influenza and pertussis vaccinations. The goal was to evaluate vaccination coverage against influenza and pertussis in pregnant women, following midwife professional advice during the pregnancy follow-up; Methods: Prospective cohort study of 1017 pregnancies during the vaccination campaign in 2015⁻2016. To estimate the degree of consistency between the coverage declared by mothers and that registered in the Nominal Vaccination Registry (NVR), we used the Cohen's kappa index (k); Results: 95.4% were registered in the NVR. Vaccination coverage recorded against influenza was 64.2% (95% CI: 61.2⁻67.2), and 89.8% (95% CI: 87.9⁻91.7) against pertussis. The coverage of the pregnant women interviewed was 61.7% (95% CI: 58.1⁻67.3)) for influenza and 92.3% (95% CI: 91.4⁻95.3) for pertussis. Subsequent interviews of 67.2% of the women produced a kappa agreement index between the data obtained from interviews and those recorded in the NVR of 0.974 (IC95%: 98.0⁻99.6) for influenza, and 0.921 (IC95%: 98.1⁻99.7) for pertussis. The women identified midwives as the main source of vaccination information and advice 88.4% (IC95%: 85.8⁻90.9); Conclusions: The NVR is an effective platform for estimating immunisation coverage in pregnant women. The degree of agreement between declared vaccinations and registered vaccinations was high for both vaccines.

Enhancing uptake of influenza maternal vaccine

INTRODUCTION

Influenza vaccination during pregnancy can offer many benefits to both mother and infant. Despite recommendations from the Advisory Committee on Immunization Practices, vaccine coverage rates among pregnant women during pregnancy are below 40% in the United States. There is a need for a greater understanding of what interventions can improve vaccine uptake among pregnant women.

AREAS COVERED

This review synthesizes the existing evidence on the effectiveness of interventions to improve maternal influenza vaccine uptake. These interventions are examined within the framework of the three psychological propositions: thoughts and feelings, social processes and changing behavior directly.

EXPERT COMMENTARY

A number of promising and effective interventions were identified in this review. Nudge-based interventions that build on favorable intentions to vaccinate such as provider prompts and standing orders have demonstrated significant success in improving influenza vaccine uptake. However, substantial gaps in the literature still exist. Provider recommendations are the most important predictor of vaccine receipt among pregnant women, yet few studies evaluated intervening to improve the dialogue between patient and provider. With the potential for even more vaccines to be added to the maternal immunization schedule, it is vitally important to understand how to improve uptake.

Do superstitious beliefs affect influenza vaccine uptake through shaping health beliefs?

BACKGROUND

This study examined the impact of superstitious beliefs on influenza vaccine uptake and investigated the role of health beliefs as underlying psychological mechanisms. It is hypothesized that superstitious beliefs predict greater perceived risks in influenza and vaccines, which in turn affect influenza vaccine uptake.

METHODS

A cross-sectional survey of Singaporeans and Singapore Permanent Residents aged between 21 and 70 (N = 668) was conducted using computer-assisted telephone interviews. The survey covered beliefs in superstition, health beliefs in influenza and vaccines, and influenza vaccine uptake intention and behavior using the Health Belief Model. Path analysis was adopted to examine the hypothesized model.

RESULTS

Approximately 60% of the sample had never obtained influenza vaccination. The path analysis found that superstitious beliefs significantly predicted higher perceived barriers and lower perceived benefits of vaccines, which in turn predicted a lower intention to take influenza vaccine in the next year and/or a lower probability of ever taking influenza vaccine. In contrast, superstitious beliefs predicted higher perceived susceptibility and severity of influenza that in turn predicted higher influenza vaccine uptake intention and/or probability. Examining demographic variables and past experience on influenza as control and confounding factors did not significantly affect the results.

CONCLUSION

The findings imply that beliefs in superstitions can have mixed effects on vaccine uptake and intention through shaping beliefs of the disease and vaccines. Significant implications in health education and persuasion on vaccine uptake are discussed.

Estimating Vaccine Effectiveness Against Hospitalized Influenza During Pregnancy: Multicountry Protocol for a Retrospective Cohort Study

Background

Although pregnant women are believed to have elevated risks of severe influenza infection and are targeted for influenza vaccination, no study to date has examined influenza vaccine effectiveness (IVE) against laboratory-confirmed influenza-associated hospitalizations during pregnancy, primarily because this outcome poses many methodological challenges.

Objective

The Pregnancy Influenza Vaccine Effectiveness Network (PREVENT) was formed in 2016 as an international collaboration with the Centers for Disease Control and Prevention; Abt Associates; and study sites in Australia, Canada, Israel, and the United States. The primary goal of this collaboration is to estimate IVE in preventing acute respiratory or febrile illness (ARFI) hospitalizations associated with laboratory-confirmed influenza virus infection during pregnancy. Secondary aims include (1) describing the incidence, clinical course, and severity of influenza-associated ARFI hospitalization during pregnancy; (2) comparing the characteristics of ARFI-hospitalized pregnant women who were tested for influenza with those who were not tested; (3) describing influenza vaccination coverage in pregnant women; and (4) comparing birth outcomes among women with laboratory-confirmed influenza-associated hospitalization versus other noninfluenza ARFI hospitalizations.

Methods

For an initial assessment of IVE, sites identified a retrospective cohort of pregnant women aged from 18 to 50 years whose pregnancies overlapped with local influenza seasons from 2010 to 2016. Pregnancies were defined as those that ended in a live birth or stillbirth of at least 20 weeks gestation. The analytic sample for the primary IVE analysis was restricted to pregnant women who were hospitalized for ARFI during site-specific influenza seasons and clinically tested for influenza virus infection using real-time reverse transcription polymerase chain reaction.

Results

We identified approximately 2 million women whose pregnancies overlapped with influenza seasons; 550,344 had at least one hospitalization during this time. After restricting to women who were hospitalized for ARFI and tested for influenza, the IVE analytic sample included 1005 women.

Conclusions

In addition to addressing the primary question about the effectiveness of influenza vaccination, PREVENT data will address other important knowledge gaps including understanding the incidence, clinical course, and severity of influenza-related hospitalizations during pregnancy. The data infrastructure and international partnerships created for these analyses may be useful and informative for future influenza studies.

International Registered Report Identifier (IRRID)

DERR1-10.2196/11333

Factors influencing refusing of flu vaccination among pregnant women in Italy: Healthcare workers' role

BACKGROUND

Pregnant women are at increased risk of influenza complications. Influenza vaccine provides them a substantial protection.

OBJECTIVE

The aim of this study was to investigate determinants associated with non-adherence to influenza vaccine recommendations in pregnant women in Italy.

METHODS

A cross-sectional study has been carried out among pregnant women attending their follow-up visit in some mother and child services in a Region of Italy from October 2016 to January 2017. The study protocol was approved by the local research Ethics. A self-administered close-ended questionnaire has been administered to the pregnant women. Differences in background, socio-demographic characteristics, knowledge and attitudes towards flu vaccine were tested in vaccinated and unvaccinated women. Multivariate analysis was performed to control for confounding factors.

RESULTS

Three hundred and sixty-six women answered the survey (97% response rate) and 96.1% (348) declared of being unvaccinated against influenza during the 2016-2017 influenza season. Frequent reasons for refusing vaccination were drugs objection and concerns about vaccines' effects. According to the refusal attitude, influenza knowledge was low in the group. Moreover, analysis showed that low adherence to vaccination is associated to lacking promotion of vaccination to pregnant women carried out by healthcare workers (P < 0.005).

CONCLUSIONS

Healthcare workers have a key role in assisting women during the gestational period, so their active involvement in vaccination promotion is essential. It is necessary to improve health care workers' knowledge about vaccine relevance in protecting pregnancy and their communication skills to properly inform pregnant women.

Cost-effectiveness of adult vaccinations: A systematic review

BACKGROUND

Coverage levels for many recommended adult vaccinations are low. The cost-effectiveness research literature on adult vaccinations has not been synthesized in recent years, which may contribute to low awareness of the value of adult vaccinations and to their under-utilization. We assessed research literature since 1980 to summarize economic evidence for adult vaccinations included on the adult immunization schedule.

METHODS

We searched PubMed, EMBASE, EconLit, and Cochrane Library from 1980 to 2016 and identified economic evaluation or cost-effectiveness analysis for vaccinations targeting persons aged ≥18 years in the U.S. or Canada. After excluding records based on title and abstract reviews, the remaining publications had a full-text review from two independent reviewers, who extracted economic values that compared vaccination to "no vaccination" scenarios.

RESULTS

The systematic searches yielded 1688 publications. After removing duplicates, off-topic publications, and publications without a "no vaccination" comparison, 78 publications were included in the final analysis (influenza = 25, pneumococcal = 18, human papillomavirus = 9, herpes zoster = 7, tetanus-diphtheria-pertussis = 9, hepatitis B = 9, and multiple vaccines = 1). Among outcomes assessing age-based vaccinations, the percent indicating cost-savings was 56% for influenza, 31% for pneumococcal, and 23% for tetanus-diphtheria-pertussis vaccinations. Among age-based vaccination outcomes reporting $/QALY, the percent of outcomes indicating a cost per QALY of ≤$100,000 was 100% for influenza, 100% for pneumococcal, 69% for human papillomavirus, 71% for herpes zoster, and 50% for tetanus-diphtheria-pertussis vaccinations.

CONCLUSIONS

The majority of published studies report favorable cost-effectiveness profiles for adult vaccinations, which supports efforts to improve the implementation of adult vaccination recommendations.

The safety of inactivated influenza vaccines in pregnancy for birth outcomes: a systematic review

Pregnant women are at increased risk of morbidity and mortality from influenza and are recognized as a priority group for influenza vaccination. Despite this, uptake is often poor and one reason cited for this is concerns about safety. The objective of this study was to perform a systematic review of the safety of inactivated influenza vaccination (IIV) in pregnancy. Studies were included if they were: (i) observational or experimental design; (ii) included a comparator group comprising of unvaccinated pregnant women; (iii) comprised of either seasonal IIV or monovalent H1N1 IIV (including adjuvanted vaccines); and (iv) addressed one of the following outcomes: preterm birth (PTB), small for gestational age (SGA), fetal death (including stillbirth or spontaneous abortion), low birth weight (LBW) or congenital abnormalities. Two reviewers screened abstracts and titles and selected full texts for retrieval. Crude odds ratios were calculated from reported event rates, using binomial standard errors. Adjusted odds ratios, hazard ratios and relative rates were extracted as reported in each paper. After removal of duplicates and full text eligibility assessment, 40 studies remained. The aOR for PTB was 0.87 (0.78–0.96), for LBW 0.82 (0.76–0.89), congenital abnormality 1.03 (0.99–1.07), SGA 0.99 (0.94–1.04) and stillbirth 0.84 (0.65–1.08). This study contributes to the increasing body of safety data for IIV in pregnancy and reports a protective effect on PTB and LBW.

Vaccination Against Influenza in Pregnancy: A Survey of Canadian Maternity Care Providers

OBJECTIVE

Influenza vaccine uptake among Canadian pregnant individuals is suboptimal. Failure to incorporate vaccination into routine prenatal care and a lack of recommendations from healthcare providers are recognized as barriers to vaccination. The aim of this study was to assess Canadian maternity care providers' knowledge, attitudes, and practices regarding influenza vaccination in pregnancy.

METHODS

A cross-sectional Web-based questionnaire was sent during July and August 2017 to family physicians, obstetricians-gynaecologists, midwives, pharmacists, and nurses who care for pregnant individuals. A multivariable logistic regression model was used to determine variables independently associated with providers' recommendation of the influenza vaccine in pregnancy.

RESULTS

The analysis included 1061 providers. Most participants (85%) reported being vaccinated against influenza themselves, and 72% reported recommending the influenza vaccine to all of their pregnant patients during the previous influenza season. Participants' attitudes regarding influenza vaccination during pregnancy were generally positive: 64% strongly agreed that pregnant individuals are at an increased risk of complications from influenza, and 69% strongly agreed that it is safe to vaccinate pregnant individuals against influenza. The main determinants of participants' recommendations for influenza vaccination to all pregnant patients were following official recommendations on influenza vaccination, discussing vaccines with most or all pregnant individuals seen in their practice, and being vaccinated themselves during the previous influenza season.

CONCLUSION

Enhancing influenza vaccine uptake in pregnancy is largely dependent on maternity care providers' recommendations. This study provides valuable insight on providers' knowledge, attitudes, and practices.