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

Factors associated with COVID-19 vaccination among pregnant women in Rio De Janeiro City, Brazil

COVID-19 vaccination during pregnancy is safe and effective in reducing the risk of complications. However, the uptake is still below targets worldwide. This study aimed to explore the factors associated with COVID-19 vaccination uptake among pregnant women since data on this topic is scarce in low-to-middle-income countries. A retrospective cohort study included linked data on COVID-19 vaccination and pregnant women who delivered a singleton live birth from August 1, 2021, to July 31, 2022, in Rio de Janeiro City, Brazil. Multiple logistic regression was performed to identify factors associated with vaccination during pregnancy, applying a hierarchical model and describing odds ratio with 95% confidence intervals. Of 65,304 pregnant women included in the study, 53.0% (95% CI, 52-53%) received at least one dose of COVID-19 vaccine during pregnancy. Higher uptake was observed among women aged older than 34 (aOR 1.21, 95%CI 1.15-1.28), black (aOR 1.10, 1.04-1.16), or parda/brown skin colour (aOR 1.05, 1.01-1.09), with less than eight years of education (aOR 1.09, 1.02-1.17), living without a partner (aOR 2.24, 2.16-2.34), more than six antenatal care appointments (aOR 1.92, 1.75-2.09), and having a previous child loss (OR 1.06, 1.02-1.11). These results highlight the need for targeted educational campaigns, trustful communication, and accessibility strategies for specific populations to improve vaccination uptake during pregnancy.

Health Systems Determinants of Delivery and Uptake of Maternal Vaccines in Low- and Middle-Income Countries: A Qualitative Systematic Review

Maternal vaccination is considered a key component of the antenatal care package for improving maternal and child health. Low- and middle-income countries (LMICs) fall short of global targets to prevent maternal and neonatal deaths, with a disproportionate burden of vaccine-preventable diseases. Strategies towards ending preventable maternal mortality necessitate a health systems approach to adequately respond to this burden. This review explores the health systems determinants of delivery and uptake of essential maternal vaccines in LMICs. We conducted a qualitative systematic review of articles on maternal vaccination in LMICs, published between 2009 and 2023 in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Thematic analysis was conducted to identify key themes in the literature, interpreted within a conceptual framing that explores the systems determinants influencing maternal vaccines. Our search yielded 1309 records, of which 54 were included, covering 34 LMICs. Most of the included studies were from South America (28/54) and included pregnant women as the primary study population (34/54). The studies explored influenza (25/54) and tetanus toxoid (20/54) vaccines predominantly. The findings suggest that systems hardware (lack of clear policy guidelines, ineffective cold-chain management, limited reporting and monitoring systems) are barriers to vaccine delivery. Systems software (healthcare provider recommendations, increased trust, higher levels of maternal education) are enablers to maternal vaccine uptake. Findings show that formulation, dissemination and communication of context-specific policies and guidelines on maternal vaccines should be a priority for decision-makers in LMICs.

Understanding Barriers and Facilitators to Maternal Immunization: A Systematic Narrative Synthesis of the Published Literature

Introduction

Vaccines are being developed against Group B Streptococcus and respiratory syncytial virus. These vaccines are designed to be given to pregnant women to protect infants; thus, their success depends on uptake in this population. Maternal immunization programs have struggled to achieve target coverage rates. This systematic narrative synthesis aims to define the most important barriers and facilitators for maternal immunization and to identify priority areas for future research.

Methods

A search strategy was developed in Medline and adapted according to the requirements of additional search engines. Two reviewers independently reviewed the studies, using pre-specified inclusion and exclusion criteria. Results sections of included studies were coded, and thematic analysis was used to identify prominent themes.

Results

321 studies were included in the final review. Most studies came from North America (37%), Europe (26%) or East Asia, Australia and New Zealand (22%). Low-and middle-income countries were under-represented. Five percent of studies came from Sub-Saharan Africa, and 2% came from South Asia. The prominent factors impacting maternal immunization were provider recommendation, perceived risks and benefits of maternal vaccines for the infant, race, birthplace, and access to healthcare. Few studies explored reasons behind racial and socioeconomic disparities in maternal immunization rates.

Discussion

A strong provider recommendation, equitable access to prenatal care and messaging that focuses on vaccine safety and infant benefits emerged as the key components for optimising vaccine uptake among pregnant women. Research among healthcare providers, minority groups and in low- and-middle-income countries was lacking. In anticipation of the expansion of maternal immunization programmes, focused research is needed to address these gaps and inform a successful public health strategy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10995-022-03508-0.

Influenza vaccination coverage in elderly and high-risk adults: characterization of associated factors

Objective

To evaluate the prevalence and factors associated with non-vaccination against influenza in the risk group.

Methods

A cross-sectional, population-based study, carried out in the city of Rio Grande (RS). The outcome was defined as belonging to risk groups and not having been vaccinated in the last 12 months. Demographic, socioeconomic, behavioral variables, and access for health services were analyzed.

Results

In this study, 680 individuals participated. The prevalence was 46.0% (95%CI: 41.8-50.3), ranging from 27.9% (elderly) to 81.8% (pregnant women). Young adults, single, intermediate socioeconomic bracket, smoker, with depressive symptoms, who did not perform physical activity and did not consult a physician in the last year, had a higher prevalence of non-vaccination.

Conclusion

Half of the sample was not vaccinated in the period. Due to the similarity of influenza-like illness and the coronavirus 2019 disease (COVID-19), increasing vaccination would minimize mortality and use of hospital beds due to influenza, optimizing the response of hospital capacity.

Tetanus vaccination in pregnant women: a systematic review and meta-analysis of the global literature

OBJECTIVES

This study aimed to determine the effect of several factors on the uptake of tetanus vaccination in pregnant women.

STUDY DESIGN

This is a systematic review and meta-analysis of the global literature.

METHODS

The search strategy was carried out in the EMBASE and MEDLINE (Pubmed) databases, without language restrictions. The databases were searched from the beginning until May 2020. Fixed and random effect models were applied according to the methodological heterogeneity between the included studies. The I² test was performed to assess the magnitude of the heterogeneity. The results were presented as a grouped odds ratio (OR) with a 95% confidence interval (CI) and a significance level of 0.05.

RESULTS

The initial search strategy generated 14,349 original articles. In total, 31 studies met all inclusion criteria and 20 articles were included in the meta-analysis. The grouped and subgroup analyses showed a significant association between tetanus vaccination and the following factors: higher number of prenatal visits (OR: 2.00; 95% CI: 1.17-3.42), higher maternal age (OR: 1.24, 95% CI: 1.02-1.50), being single (OR: 1.41; 95% CI: 1.20-1.65), professional vaccine guidance (OR: 9.00; 95% CI: 1.81-44.75) and uptake of influenza vaccine (OR: 5.87; 95% CI: 1.39-24.73).

CONCLUSIONS

The uptake of tetanus vaccine in pregnant women is associated with various factors. The identification of these factors is an important step towards the implementation of public health strategies aimed at improving immunisation against tetanus in pregnant women.

Sociodemographic and health-related determinants of seasonal influenza vaccination in pregnancy: A systematic review and meta-analysis of the evidence since 2000

INTRODUCTION

Vaccination is considered to be the most practical and effective preventative measure against influenza. It is highly recommended for population subgroups most at risk of developing complications, including pregnant women. However, seasonal influenza vaccine uptake remains suboptimal among pregnant women, even in jurisdictions with universal vaccination. We summarized the evidence on the determinants of seasonal influenza vaccine uptake during pregnancy to better understand factors that influence vaccine uptake among pregnant women.

MATERIAL AND METHODS

We systematically searched MEDLINE, Embase and CINAHL from January 2000 to February 2020 for publications in English reporting on sociodemographic and/or health-related determinants of seasonal influenza vaccine uptake during pregnancy. Two reviewers independently included studies. One reviewer extracted data and assessed study quality, and another reviewer checked extracted data and study quality assessments for errors. Disagreements were resolved through consensus, or a third reviewer. We meta-analyzed using the inverse variance, random-effects method, and reported the odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

From 1663 retrieved citations, we included 36 studies. The following factors were associated with increased seasonal influenza vaccine uptake: Older age (20 studies: OR 1.13, 95% CI 1.07-1.20), being nulliparous (13 studies: OR 1.26, 95% CI 1.15-1.38), married (8 studies: OR 1.11, 95% CI 1.07-1.15), employed (4 studies: OR 1.13, 95% CI 1.02-1.24), a non-smoker (8 studies: OR 1.25, 95% CI 1.04-1.51) and having prenatal care (3 studies: OR 3.36, 95% CI 2.25-5.02), a chronic condition (6 studies: OR 1.30, 95% CI 1.17-1.44), been previously vaccinated (9 studies: OR 4.88, 95% CI 3.14-7.57) and living in a rural area (9 studies: OR 1.09, 95% CI 1.05-1.14). Compared with being black, being white was also associated with increased seasonal influenza vaccine uptake (11 studies: OR 1.30, 95% CI 1.20-1.41).

CONCLUSIONS

The evidence suggests that several sociodemographic and health-related factors may determine seasonal influenza vaccination in pregnancy, and that parity, history of influenza vaccination, prenatal care and comorbidity status may be influential.