Influenza-Associated Outcomes Among Pregnant, Postpartum, and Nonpregnant Women of Reproductive Age

Vaccine Acceptance Among Pregnant Women in Israel During COVID-19: Influences and Decision-Making Factors

Background and Objectives: In response to the COVID-19 pandemic, Israel prioritized pregnant women for vaccination, recognizing them as a high-risk group. This study aims to explore factors influencing the acceptance of Influenza, Pertussis (T-dap), and COVID-19 vaccines among pregnant women, focusing on attitudes, social norms, perceived control, and risk perceptions. Additionally, the study compares acceptance patterns between traditional vaccines and the newer COVID-19 vaccine. Methods: A prospective cohort study was conducted between December 2019 and December 2021 involving 449 predominantly Israeli pregnant women. A survey was administered to gather data on demographics, obstetric history, vaccination history, and factors influencing vaccination decisions. Results: COVID-19 vaccine uptake was the highest at 64% (202/314), followed by T-dap at 49% (221/449) and Influenza at 32% (146/449). Multivariable logistic regression showed that non-religious women and those with academic education were more likely to accept vaccines, especially the COVID-19 vaccine. Physician recommendations were the most influential factor in vaccine acceptance, while internet and media sources played a significant role in shaping COVID-19 vaccine decisions. Perceived risks varied: Whooping Cough was seen as the greatest threat to newborns, while COVID-19 posed the highest risk to mothers. Analyzing maternal and neonatal disease perception using multivariable linear regression, we found that information on maternal and neonatal Flu, Whooping Cough, and COVID-19 was significantly positively correlated with disease perception for each condition. Conclusions: Healthcare providers play a crucial role in influencing vaccine decisions, especially through personalized communication. Strategies targeting religious communities and leveraging media can help address vaccine hesitancy, ultimately improving maternal and neonatal health outcomes.

Birth Outcomes After Pertussis and Influenza Diagnosed in Pregnancy: A Retrospective, Population-Based Study

OBJECTIVE

Adverse birth outcomes and the maternal severity of influenza in pregnancy are well documented but information on pertussis is limited.

DESIGN

Population-based linkage data were collected during 2001-2016.

SETTING

New South Wales, Australia.

POPULATION OR SAMPLE

A total of 1 453 037 singleton births.

METHODS

Cox regression was used to estimate the associations between pertussis or influenza during pregnancy and birth outcomes with adjustment of covariates.

MAIN OUTCOME MEASURES

Adverse birth outcomes (preterm birth and low birth weight).

RESULTS

Among 1 453 037 singleton births over 16 years, we identified pertussis in 925 (49; 5.3% hospitalised) and influenza in 2850 (1092; 38.3% hospitalised) women during pregnancy. Cases of pertussis were similarly distributed by trimester (32% 3rd) whereas 46% of influenza cases were in the 3rd trimester. Younger age, previous birth, and being overseas-born were associated with both pertussis and influenza, whereas identifying as Aboriginal or Torres Strait Islander, hypertension or diabetes before and during pregnancy, and a number of other factors were only associated with influenza. Both pertussis and influenza in pregnancy were associated with increased risk of preterm birth (pertussis: aHR = 1.30, 95% CI 1.01-1.68; influenza: aHR = 1.56, 95% CI 1.36-1.79) and these increased risks were greater when infections in the period within 2 weeks of birth were considered (pertussis: aHR = 2.36, 95% CI 1.26-4.41; influenza: aHR = 2.29, 95% CI 1.78-2.96).

CONCLUSIONS

Maternal pertussis and influenza infections close to the time of birth were associated with adverse birth outcomes. These findings highlight the benefits of vaccination during pregnancy.

Defining the balance between optimal immunity and immunopathology in influenza virus infection

Influenza A viruses remain a global threat to human health, with continued pandemic potential. In this Review, we discuss our current understanding of the optimal immune responses that drive recovery from influenza virus infection, highlighting the fine balance between protective immune mechanisms and detrimental immunopathology. We describe the contribution of innate and adaptive immune cells, inflammatory modulators and antibodies to influenza virus-specific immunity, inflammation and immunopathology. We highlight recent human influenza virus challenge studies that advance our understanding of susceptibility to influenza and determinants of symptomatic disease. We also describe studies of influenza virus-specific immunity in high-risk groups following infection and vaccination that inform the design of future vaccines to promote optimal antiviral immunity, particularly in vulnerable populations. Finally, we draw on lessons from the COVID-19 pandemic to refocus our attention to the ever-changing, highly mutable influenza A virus, predicted to cause future global pandemics.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Maternal immunization with distinct influenza vaccine platforms elicits unique antibody profiles that impact the protection of offspring

Pregnant women and infants are considered high-risk groups for increased influenza disease severity. While influenza virus vaccines are recommended during pregnancy, infants cannot be vaccinated until at least six months of age. Passive transfer of maternal antibodies (matAbs) becomes vital for the infant's protection. Here, we employed an ultrasound-based timed-pregnancy murine model and examined matAb responses to distinct influenza vaccine platforms and influenza A virus (IAV) infection in dams and their offspring. We demonstrate vaccinating dams with a live-attenuated influenza virus (LAIV) vaccine or recombinant hemagglutinin (rHA) proteins administered with adjuvant resulted in enhanced and long-lasting immunity and protection from influenza in offspring. In contrast, a trivalent split-inactivated vaccine (TIV) afforded limited protection in our model. By cross-fostering pups, we show the timing of antibody transfer from vaccinated dams to their offspring (prenatal versus postnatal) can shape the antibody profile depending on the vaccine platform. Our studies provide information on how distinct influenza vaccines lead to immunogenicity and efficacy during pregnancy, impact the protection of their offspring, and detail roles for IgG1 and IgG2c in the development of vaccine administration during pregnancy that stimulate and measure expression of both antibody subclasses.

Interventions to improve vaccine coverage of pregnant women in Aotearoa New Zealand

Introduction Maternal vaccination against influenza and pertussis protects mothers and babies from severe disease and is recommended and funded in Aotearoa New Zealand. Despite this, maternal vaccination uptake is low, varies by region and is inequitable, with Māori and Pacific māmā (mothers) less likely to receive vaccination. Aim To determine what interventions currently exist to support and encourage maternal vaccination against influenza and pertussis and what changes and interventions could be implemented to improve coverage, with a focus on Māori and Pacific hapū māmā (pregnant mothers). Methods Interviews with six participants with diverse roles in the vaccination workforce were conducted. Participants were involved in education, certification and supporting vaccinators, high-level strategising, and vaccination. Interviews aimed to determine what interventions currently exist for hapū māmā, what changes need to be made to improve coverage and how Māori and Pacific people have been specifically engaged. Qualitative data analysis was used to determine themes. Results Participants identified that interventions must focus on prioritising and emphasising the importance of maternal vaccination, promoting collaboration and innovation, making interventions accessible, and empowering Māori- and Pacific-driven avenues to vaccination. To create positive foundations, participants identified the importance of building and maintaining trust and affording mothers' time and autonomy in vaccination. Discussion Healthcare professionals need to proactively engage hapū māmā about vaccination and collaborate in service delivery. Interventions must be suitably accessible and allow for the autonomy of hapū māmā over vaccination decisions. Equity should be considered at the foundation of vaccine interventions to improve the accessibility of vaccines to all communities.

Influenza Vaccination Among Pregnant Women: Self-report Compared With Vaccination Data From Electronic Health Records, 2018-2020 Influenza Seasons

OBJECTIVES

Having accurate influenza vaccination coverage estimates can guide public health activities. The objectives of this study were to (1) validate the accuracy of electronic health record (EHR)-based influenza vaccination data among pregnant women compared with survey self-report and (2) assess whether survey respondents differed from survey nonrespondents by demographic characteristics and EHR-based vaccination status.

METHODS

This study was conducted in the Vaccine Safety Datalink, a network of 8 large medical care organizations in the United States. Using EHR data, we identified all women pregnant during the 2018-2019 or 2019-2020 influenza seasons. Surveys were conducted among samples of women who did and did not appear vaccinated for influenza according to EHR data. Separate surveys were conducted after each influenza season, and respondents reported their influenza vaccination status. Analyses accounted for the stratified design, sampling probability, and response probability.

RESULTS

The survey response rate was 50.5% (630 of 1247) for 2018-2019 and 41.2% (721 of 1748) for 2019-2020. In multivariable analyses combining both survey years, non-Hispanic Black pregnant women had 3.80 (95% CI, 2.13-6.74) times the adjusted odds of survey nonresponse; odds of nonresponse were also higher for Hispanic pregnant women and women who had not received (per EHR data) influenza vaccine during current or prior influenza seasons. The sensitivity, specificity, and positive predictive value of EHR documentation of influenza vaccination compared with self-report were ≥92% for both survey years combined. The negative predictive value of EHR-based influenza vaccine status was 80.5% (95% CI, 76.7%-84.0%).

CONCLUSIONS

EHR-based influenza vaccination data among pregnant women were generally concordant with self-report. New data sources and novel approaches to mitigating nonresponse bias may be needed to enhance influenza vaccination surveillance efforts.

Influenza-associated hospitalisation and mortality rates among global Indigenous populations; a systematic review and meta-analysis

BACKGROUND

More than 50 million influenza infections and over 100,000 deaths from influenza occur annually. While Indigenous populations experience an inequitable influenza burden, the magnitude of this inequity has not previously been estimated on a global scale. This study compared rates of influenza-associated hospitalisation and mortality between Indigenous and non-Indigenous populations globally.

METHODS

A systematic review and meta-analysis was conducted including literature published prior to 13 July 2021. Eligible articles either reported a rate ratio (RR) comparing laboratory-confirmed influenza-associated hospitalisation and/or mortality between an Indigenous population and a corresponding benchmark population, or reported sufficient information for this to be calculated using publicly available data. Findings were reported by country/region and pooled by country and period (pandemic/seasonal) when multiple studies were available using a random-effects model. The I2 statistic assessed variability between studies.

RESULTS

Thirty-six studies (moderate/high quality) were included; all from high or high-middle income countries. The pooled influenza-associated hospitalisation RR (HRR) for indigenous compared to benchmark populations was 5·7 (95% CI: 2·7-12·0) for Canada, 5·2 (2.9-9.3) for New Zealand, and 5.2 (4.2-6.4) for Australia. Of the Australian studies, the pooled HRR for seasonal influenza was 3.1 (2·7-3·5) and for pandemic influenza was 6·2 (5·1-7·5). Heterogeneity was slightly higher among studies of pandemic influenza than seasonal influenza. The pooled mortality RR was 4.1 (3·0-5.7) in Australia and 3·3 (2.7-4.1) in the United States.

CONCLUSIONS

Ethnic inequities in severe influenza persist and must be addressed by reducing disparities in the underlying determinants of health. Influenza surveillance systems worldwide should include Indigenous status to determine the extent of the disease burden among Indigenous populations. Ethnic inequities in pandemic influenza illustrate the need to prioritise Indigenous populations in pandemic response plans.

Mapping the maternal vaccination journey and influencing factors for Māori women in Aotearoa New Zealand: a qualitative study

Introduction Uptake of maternal vaccinations (MVs) is suboptimal in Aotearoa New Zealand, particularly for Māori. Aim To describe Māori women's journeys regarding maternal pertussis and influenza vaccinations and explore influences on uptake. Methods Semi-structured interviews were conducted in Waikato, Aotearoa New Zealand, with pregnant or recently pregnant Māori women, and separately with Māori healthcare professionals (HCPs) to understand women's decisions regarding MVs and enablers and barriers to uptake. Results Nine women and nine HCPs were interviewed. Verbal communications from midwives, general practice and pharmacy strongly influenced women's journeys. Women's decisions appeared largely straight-forward, with influences including awareness, knowledge, underlying beliefs and previous MVs. Enablers for MV uptake included HCPs' discussions, pro-vaccination beliefs, and accessibility. Barriers for MV uptake included poverty (and transport), lack of awareness, insufficient knowledge of benefits, late presentation to the midwife and other commitments or challenges in the women's lives affecting prioritisation of the vaccine. Misconceptions, seasonality, and lower HCP emphasis impaired influenza vaccination uptake. Discussion With multiple barriers to accessing MVs, HCPs who see pregnant women are the primary resource to improve awareness, knowledge, and access through kōrero (discussions) with the woman and, where possible, being able to administer the vaccinations. These HCPs need to be well-informed, aware of likely concerns women may have and how to address them, encourage these discussions and preferably be trusted.

High Expression Level of α2-3-Linked Sialic Acids on Salivary Glycoproteins of Breastfeeding Women May Help to Protect Them from Avian Influenza Virus Infection

Terminal sialic acids (Sia) on soluble glycoprotein of saliva play an important role in the clearance of influenza virus. The aim of this study is to investigate the alteration of sialylation on the salivary proteins of women during the lactation period and its effect on the saliva binding ability to virus. In total, 210 saliva samples from postpartum women with and without breastfeeding were collected, and the expression level of α2-3/6-linked Sia on the whole salivary proteins and specific glycoproteins of IgA and MUC5B from different groups were tested and verified using lectin microarray, blotting analysis and ELISA based method. The H1N1 vaccine and three strains of Avian influenza virus (AIV) were used for the saliva binding assay. Results showed that the variation in salivary expression level of α2-3-linked Sia was much more obvious than the α2-6-linked Sia, which was up-regulated significantly in the breastfeeding groups compared to the non-breastfeeding groups at the same postpartum stage. Furthermore, the binding abilities of salivary glycoproteins to AIV strains and H1N1 vaccine were increased in breastfeeding groups accordingly. This finding adds new evidence for the maternal benefit of breastfeeding and provides new thinking to protect postpartum women from AIV infection.

Determinants of maternal influenza vaccination in the context of low- and middle-income countries: A systematic review

BACKGROUND

Pregnancy and early infancy are considered to be the vulnerable phases for severe influenza infection causing morbidity and mortality. Despite WHO recommendations, influenza is not included in the immunization programs of many low- and middle-income countries. This systematic review is aimed at identifying barriers and facilitators for maternal influenza vaccination amongst the perinatal women and their health care providers in low- and middle-income countries.

METHODS

We selected 11 studies from the 1669 records identified from PubMed, CABI, EMBASE and Global Health databases. Studies related to both pandemic and routine influenza vaccination and studies conducted amongst women in the antenatal as well as postnatal period were included. Both qualitative, quantitative, cross-sectional and interventional studies were included.

RESULTS

Knowledge about influenza disease, perception of the disease severity during pregnancy and risk to the foetus/newborn and perceived benefits of influenza vaccination during pregnancy were associated with increased uptake of influenza vaccination during pregnancy. Recommendation by health care provider, vaccination in previous pregnancy and availability of vaccine in public health system facilitated vaccine uptake. High parity, higher education, vaccination in the later months of pregnancy, less than 4 antenatal visits, concerns about vaccine safety and negative publicity in media were identified as barriers for influenza vaccination. Lack of government recommendation, concerns about safety and effectiveness and distrust in manufacturer were the barriers for the healthcare providers to recommend vaccination.

CONCLUSION

While availability of influenza vaccine in public health system can be a key to the success of vaccine implementation program, increasing the awareness about need and benefits of maternal influenza vaccination amongst pregnant women as well as their health care providers is crucial to improve the acceptance of maternal influenza vaccination in low and middle-income countries.

Influences on Pregnant Women's and Health Care Professionals' Behaviour Regarding Maternal Vaccinations: A Qualitative Interview Study

The uptake of maternal influenza and pertussis vaccinations is often suboptimal. This study explores the factors influencing pregnant women's and health care professionals' (HCPs) behaviour regarding maternal vaccinations (MVs). Pregnant/recently pregnant women, midwives, pharmacists and general practice staff in Waikato, New Zealand, were interviewed. The analysis used the behaviour change wheel model. Interviews of 18 women and 35 HCPs revealed knowledge about MVs varied with knowledge deficiencies hindering the uptake, particularly for influenza vaccination. HCPs, especially midwives, were key in raising women's awareness of MVs. Experience with vaccinating, hospital work (for midwives) and training increased HCPs' knowledge and proactivity about MVs. A "woman's choice" philosophy saw midwives typically encouraging women to seek information and make their own decision. Women's decisions were generally based on knowledge, beliefs, HCPs' emphasis and their perceived risk, with little apparent influence from friends, family, or online or promotional material. General practice's concentration on children's vaccination and minimal antenatal contact limited proactivity with MVs. Busyness and prioritisation appeared to affect HCPs' proactivity. Multi-pronged interventions targeting HCPs and pregnant women and increasing MV access are needed. All HCPs seeing pregnant women should be well-informed about MVs, including how to identify and address women's questions or concerns about MVs to optimise uptake.

Cost-effectiveness of seasonal influenza vaccination in pregnant women, healthcare workers and adults >= 60 years of age in Lao People's Democratic Republic

BACKGROUND

Pregnant women, healthcare workers (HW), and adults >= 60 years have shown an increased vulnerability to seasonal influenza virus infections and/or complications. In 2012, the Lao People's Democratic Republic (Lao PDR) initiated a national influenza vaccination program for these target groups. A cost-effectiveness evaluation of this program was undertaken to inform program sustainability.

METHODS

We designed a decision-analytical model and collected influenza-related medical resource utilization and cost data, including indirect costs. Model inputs were obtained from medical record abstraction, interviews of patients and staff at hospitals in the national influenza sentinel surveillance system and/or from literature reviews. We compared the annual disease and economic impact of influenza illnesses in each of the target groups in Lao PDR under scenarios of no vaccination and vaccination, and then estimated the cost-effectiveness of the vaccination program. We performed sensitivity analyses to identify influential variables.

RESULTS

Overall, the vaccination of pregnant women, HWs, and adults >= 60 years could annually save 11,474 doctor visits, 1,961 days of hospitalizations, 43,027 days of work, and 1,416 life-years due to laboratory-confirmed influenza illness. After comparing the total vaccination program costs of 23.4 billion Kip, to the 18.4 billion Kip saved through vaccination, we estimated the vaccination program to incur a net cost of five billion Kip (599,391 USD) annually. The incremental cost per life-year saved (ICER) was 44 million Kip (5,295 USD) and 6.9 million Kip (825 USD) for pregnant women and adults >= 60 years, respectively. However, vaccinating HWs provided societal cost-savings, returning 2.88 Kip for every single Kip invested. Influenza vaccine effectiveness, attack rate and illness duration were the most influential variables to the model.

CONCLUSION

Providing influenza vaccination to HWs in Lao PDR is cost-saving while vaccinating pregnant women and adults >= 60 is cost-effective and highly cost-effective, respectively, per WHO standards.

Dyspnea and COVID-19: A Review of Confounding Diagnoses during the Postpartum Period

The puerperium is a complex period that begins with placental delivery and lasts for 6 weeks, during which readaptation of the female organism and redistribution of blood volume occur. This period is conducive to the occurrence of thromboembolic events. In the context of the SARS-CoV-2 pandemic, the virus responsible for COVID-19, the attention of the scientific community and health professionals has been focused on obtaining insights on different aspects of this disease, including etiology, transmission, diagnosis, and treatment. Regarding the pregnancy-postpartum cycle, it is opportune to review the clinical conditions that can occur during this period and to investigate dyspnea as a postpartum symptom in order to avoid its immediate association with COVID-19 without further investigation, which can lead to overlooking the diagnosis of other important and occasionally fatal conditions.

Serological Responses to Influenza Vaccination during Pregnancy

Pregnant women, newborns, and infants under six months old are at the highest risk of developing severe and even fatal influenza. This risk is compounded by the inability to vaccinate infants under six months, highlighting the importance of vertically transferred immunity. This review identifies novel insights that have emerged from recent studies using animal models of pregnancy and vaccination. We also discuss the knowledge obtained using existing clinical trials that have evaluated influenza-specific serological responses in pregnant women and how these responses may impact early life immunity. We delineate the mechanisms involved in transferring specific maternal antibodies and discuss the consequences for early life immunity. Most importantly, we highlight the need for continued research using pregnant animal models and the inclusion of pregnant women, a commonly neglected population, when evaluating novel vaccine platforms to better serve and treat communicable diseases.

Incidence rates of influenza illness during pregnancy in Suzhou, China, 2015-2018

Background

Data on influenza incidence during pregnancy in China are limited.

Methods

From October 2015 to September 2018, we conducted active surveillance for acute respiratory illness (ARI) among women during pregnancy. Nurses conducted twice weekly phone and text message follow‐up upon enrollment until delivery to identify new episodes of ARI. Nasal and throat swabs were collected ≤10 days from illness onset to detect influenza.

Results

In total, we enrolled 18 724 pregnant women median aged 28 years old, 37% in first trimester, 48% in second trimester, and 15% in third trimester, with seven self‐reported influenza vaccination during pregnancy. In the 18‐week epidemic period during October 2015 to September 2016, influenza incidence was 0.7/100 person‐months (95% CI: 0.5–0.9). In the cumulative 29‐week‐long epidemic during October 2016 to September 2017, influenza incidence was 1.0/100 person‐months (95% CI: 0.8–1.2). In the 11‐week epidemic period during October 2017 to September 2018, influenza incidence was 2.1/100 person‐months (95% CI: 1.9–2.4). Influenza incidence was similar by trimester. More than half of the total influenza illnesses had no elevated temperature and cough. Most influenza‐associated ARIs were mild, and <5.1% required hospitalization.

Conclusions

Influenza illness in all trimesters of pregnancy was common. These data may help inform decisions regarding the use of influenza vaccine to prevent influenza during pregnancy.

Racial disparities in influenza immunization during pregnancy in the United States: A narrative review of the evidence for disparities and potential interventions

OBJECTIVE

The objectives of this review were to summarize existing data on racial disparities in maternal immunization for influenza in the U.S. and to review the literature on interventions to improve the uptake of the influenza vaccine among Black pregnant women.

DATA SOURCES

U.S. survey data on maternal influenza immunization by racial and ethnic group were summarized in narrative form. To review intervention studies, PubMed, CINAHL, EMBASE, and the Cochrane Library databases were searched for English language articles published 2017 to 2021, in addition to studies identified by a previous systematic review.

STUDY ELIGIBILITY CRITERIA

Peer-reviewed studies conducted in the U.S. and reporting interventions designed to increase the uptake of the influenza vaccine in pregnancy with study populations including at least 20% of participants identifying as Black were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Studies were grouped and reviewed in a narrative manner according to whether they were conducted in predominantly Black populations or in more racially diverse populations, and whether they tested multicomponent or single-component interventions.

RESULTS

A decade of survey data show that Black women in the U.S. consistently have the lowest rate of influenza immunization in pregnancy. Black women report a lower rate of being recommended or offered the vaccine, and provider recommendation is associated with greater vaccine uptake. Intervention studies to increase influenza immunization among Black pregnant women have reported mixed results. Successful interventions include multicomponent practice-based interventions, group prenatal care, and culturally competent patient educational messages.

CONCLUSIONS

Racial disparities in maternal uptake of the influenza vaccine are long-standing, but not intractable. More research is needed to test interventions to address this disparity, with a focus on increasing provider recommendation and offer of the vaccine, addressing patients' concerns about vaccine safety and efficacy, improving providers' cultural competence, and building trust between providers and patients.

Use of an Evidence-Based Approach to Improve Influenza Vaccination Uptake in Pregnancy

INTRODUCTION

Influenza can be a significant health threat for any affected individual. Pregnant women are a high-risk population because of the likelihood of developing severe disease. Although the influenza vaccine has been recommended for use by pregnant women since 2004, current vaccination rates among pregnant women are lower than the general population and other high-risk groups.

PROCESS

A quality improvement project was undertaken during the 2019-to-2020 influenza season to increase the uptake of the influenza vaccine by women who were pregnant. The primary objective of the project was to increase the influenza vaccination rate compared with the rate in the previous season. The project had a secondary objective of standardizing documentation of the patient's vaccination status in the health record to capture data for performance measures. Interventions directed at patients, health care providers, and the health care system were simultaneously implemented as recommended by the Community Preventive Services Task Force.

OUTCOMES

Data were collected from 2967 records with 1480 from the 2018-to-2019 season and 1487 from the 2019-to-2020 season. Compared with records from the 2018-to-2019 season, the rate of those associated with a documented influenza vaccine was higher in the 2019-to-2020 season (63% vs 59%; P = .01). The rate of records without vaccination status codes was significantly less in the 2019-to-2020 season compared with the 2018-to-2019 season (14% vs 23%; P < .001).

DISCUSSION

Although interventions were effective in improving influenza vaccination uptake among pregnant women, vaccination rates still remain below the 80% goal set by the US Department of Health and Human Services. Bundled interventions have proven to be more effective than individual interventions, although which interventions are most effective remains unclear.

Epidemiology of 631 Cases of COVID-19 Identified in Jiangsu Province Between January 1st and March 20th 2020: Factors Associated with Disease Severity and Analysis of Zero Mortality

BACKGROUND This retrospective study aimed to investigate the factors associated with disease severity and patient outcomes in 631 patients with COVID-19 who were reported to the Jiangsu Commission of Health between January 1 and March 20, 2020. MATERIAL AND METHODS We conducted an epidemiological investigation enrolling 631 patients with laboratory-confirmed COVID-19 from our clinic from January to March 2020. Patients' information was collected through a standard questionnaire. Then, we described the patients' epidemiological characteristics, analyzed risk factors associated with disease severity, and assessed causes of zero mortality. Additionally, some key technologies for epidemic prevention and control were identified. RESULTS Of the 631 patients, 8.46% (n=53) were severe cases, and no deaths were recorded (n=0). The epidemic of COVID-19 has gone through 4 stages: a sporadic phase, an exponential growth phase, a peak plateau phase, and a declining phase. The proportion of severe cases was significantly different among the 4 stages and 13 municipal prefectures (P<0.001). Factors including age >65 years old, underlying medical conditions, highest fever >39.0°C, dyspnea, and lymphocytopenia (<1.0×10⁹/L) were early warning signs of disease severity (P<0.05). In contrast, earlier clinic visits were associated with better patient outcomes (P=0.029). Further, the viral load was a potentially useful marker associated with COVID-19 infection severity. CONCLUSIONS The study findings from the beginning of the COVID-19 epidemic in Jiangsu Province, China showed that patients who were more than 65 years of age and with comorbidities and presented with a fever of more than 39.0°C developed more severe disease. However, mortality was prevented in this initial patient population by early supportive clinical management.

The effect of influenza virus infection on pregnancy outcomes: A systematic review and meta-analysis of cohort studies

BACKGROUND

Adverse pregnancy outcomes are risk factors for neonatal mortality and morbidity. While some studies have demonstrated notable associations between influenza and adverse pregnancy outcomes, the findings have contrasted with other studies. This meta-analysis was conducted to assess the effect of influenza infection on pregnancy outcomes.

METHODS

We searched PubMed, Embase, Cochrane Library and Web of Science from inception to 4 November 2020. Relative risks (RRs) with 95% confidence intervals (CIs) were pooled using random-effects or fixed-effects models.

RESULTS

A total of 17 studies involving 2,351,204 participants were included. Influenza infection increased the risk of stillbirth (RR = 3.62, 95% CI: 1.60-8.20), with no significant effect on preterm birth (RR = 1.17, 95%CI: 0.95-1.45), fetal death (RR = 0.93, 95%CI: 0.73-1.18), small for gestational age (SGA) (RR = 1.10, 95%CI: 0.98-1.24) and low birth weight (LBW) (RR = 1.88, 95%CI: 0.46-7.66). In a subgroup analysis of LBW, the association was evident in studies conducted during the 2009 H1N1 pandemic (RR = 2.28, 95%CI: 1.81-2.87), with no evidence of an association in pre-pandemic or post-pandemic studies.

CONCLUSIONS

Influenza virus infection was associated with an increased risk of stillbirth, but its effect on preterm birth, fetal death, SGA and LBW is still uncertain.

Vaccination of pregnant women against influenza: what is the optimal timing?

Pregnant women and young infants are at increased risk for severe influenza and its complications. Influenza vaccination during pregnancy is increasingly implemented as a strategy aiming to protect the pregnant woman, the fetus and the young infant. In clinical practice, the achievement of satisfactory protection for the pregnant woman without compromising the protection of her infant during the first months of life remains a challenge. Determinants that are implicated in the optimal timing of influenza vaccination in pregnancy include influenza season, trimester of pregnancy, maternal host factors and infant factors. This article addresses influenza vaccination in pregnancy and presents recent published evidence on issues that affect the optimization of the timing of maternal vaccination.

Incidence, risk factors and impact of seasonal influenza in pregnancy: A national cohort study

BACKGROUND

Pregnant women are particularly vulnerable to severe infection from influenza resulting in poor neonatal outcomes. The majority of evidence relates to pandemic 2009 A/H1N1 influenza. The objective of this study was to describe the characteristics and outcomes of pregnant women hospitalised with seasonal influenza.

METHODS

This national, prospective, observational cohort study used the UK Obstetric Surveillance System (UKOSS) to identify all pregnant women admitted to hospital between 01/11/2016 and 31/10/2018 with laboratory confirmed influenza at any gestation and up to two days after giving birth. These were compared to women admitted to give birth that did not have influenza. Baseline characteristics, immunization status, maternal and perinatal outcomes were compared.

RESULTS

There were 405 women admitted to hospital with laboratory confirmed influenza in pregnancy: 2.7 per 10,000 maternities. Compared to 694 comparison women, women with influenza were less likely to be professionally employed (aOR 0.59, 95%CI 0.39-0.89) or immunised in the relevant season (aOR 0·59, 0·39-0·89) and more likely to have asthma (aOR 2.42, 1.30-4.49) or have had a previous pregnancy complication (aOR 2·47, 1·33-4·61). They were more likely to be admitted to intensive care (aOR 21.3, 2.78-163.1) and to have a cesarean birth (aOR 1·42, 1·02-1.98). Their babies were more likely to be admitted to neonatal intensive care (aOR 1.86, 1·01-3·42).

CONCLUSIONS

Immunization reduces the risk of hospitalisation with influenza in pregnancy which is associated with increased risk of morbidity for both the mother and baby. There is a continued need to increase awareness of safety and effectiveness of immunization in pregnancy and provision within antenatal care settings, especially for high-risk groups.

Outcomes of Maternal-Newborn Dyads After Maternal SARS-CoV-2

BACKGROUND AND OBJECTIVES

Infection with a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. There are limited data describing the impact of SARS-CoV-2 infection on pregnant mothers and their newborns. The objective of this study is to describe characteristics and outcomes of maternal-newborn dyads with confirmed maternal SARS-CoV-2.

METHODS

This was a multicenter, observational, descriptive cohort study with data collection from charts of maternal-newborn dyads who delivered at 4 major New York City metropolitan area hospitals between March 1 and May 10, 2020, with maternal SARS-CoV-2 infection.

RESULTS

There were a total of 149 mothers with SARS-CoV-2 infection and 149 newborns analyzed (3 sets of twins; 3 stillbirths). Forty percent of these mothers were asymptomatic. Approximately 15% of symptomatic mothers required some form of respiratory support, and 8% required intubation. Eighteen newborns (12%) were admitted to the ICU. Fifteen (10%) were born preterm, and 5 (3%) required mechanical ventilation. Symptomatic mothers had more premature deliveries (16% vs 3%, P = .02), and their newborns were more likely to require intensive care (19% vs 2%, P = .001) than asymptomatic mothers. One newborn tested positive for SARS-CoV-2, which was considered a case of horizontal postnatal transmission.

CONCLUSIONS

Although there was no distinct evidence of vertical transmission from mothers with SARS-CoV-2 to their newborns, we did observe perinatal morbidities among both mothers and newborns. Symptomatic mothers were more likely to experience premature delivery and their newborns to require intensive care.

Impact of influenza virus during pregnancy: from disease severity to vaccine efficacy

Pregnant women are among the individuals at the highest risk for severe influenza virus infection. Infection of the mother during pregnancy increases the probability of adverse fetal outcomes such as small for gestational age, preterm birth and fetal death. Animal models of syngeneic and allogeneic mating can recapitulate the increased disease severity observed in pregnant women and are used to define the mechanism(s) of that increased severity. This review focuses on influenza A virus pathogenesis, the unique immunological landscape during pregnancy, the impact of maternal influenza virus infection on the fetus and the immune responses at the maternal–fetal interface. Finally, we summarize the importance of immunization and antiviral treatment in this population and highlight issues that warrant further investigation.

[Obstetric Anesthesia During the SARS-CoV-2 Pandemic - a Brief Overview of Published Recommendations for Action by National and International Specialist Societies and Committees]

The most common human corona viruses cause common colds. But three of these viruses cause more serious, acute diseases; Middle East Respiratory Syndrome (MERS by MERS-CoV), Severe Acute Respiratory Syndrome (SARS) by SARS-CoV and COVID-19 by SARS-CoV-2. The current outbreak was classified by the WHO as a "global public health emergency". Despite all efforts to reduce the surgical lists and to cancel or postpone non-time-critical surgical interventions, some surgical and anesthetic interventions outside of intensive care medicine are still necessary and must be performed. This is particularly true for obstetric interventions and neuraxial labor analgesia. Workload in the delivery room is presumably not going to decrease and planned cesarean sections cannot be postponed. In the meantime, the clinical course and outcome of some COVID-19 patients with an existing pregnancy or peripartum courses have been reported. There are already numerous recommendations from national and international bodies regarding the care of such patients. Some of these recommendations will be summarized in this manuscript. The selection of aspects should by no means be seen as a form of prioritization. The general treatment principles in dealing with COVID-19 patients and the recommendations for action in intensive care therapy also apply to pregnant and postpartum patients. In this respect, there are naturally considerable redundancies and only a few aspects apply strictly or exclusively to the cohort of obstetric patients. In summary, at present it must be stated that the general care recommendations that also apply to non-COVID-19 patients are initially valid with regard to obstetric anesthesia. Nevertheless, the special requirements on the part of hygiene and infection protection result in special circumstances that should be taken into account when caring for pregnant patients from an anesthetic point of view. These relate to both medical aspects, but also to a particular extent logistics issues with regard to spatial separation, staffing and material resources.

Vaccinating pregnant women against influenza needs to be a priority for all countries: An expert commentary

BACKGROUND

In 2012, the World Health Organization recommended influenza vaccination for all pregnant women worldwide and the prioritisation of pregnant women in national influenza vaccination programmes. Nevertheless, vaccination rates in pregnant women often remain much lower than national targets.

OBJECTIVES

To assess the benefits and risks associated with influenza infection and vaccination during pregnancy, and to consider obstacles that work against influenza vaccine uptake during pregnancy.

RESULTS

There is strong evidence that maternal and foetal outcomes can be compromised if women develop influenza infections during pregnancy. Influenza vaccines have been administered to millions of pregnant women and have demonstrated benefits in terms of disease prevention in mothers and their infants. There is a consensus amongst several recommending authorities that influenza vaccines may be safely administered during all stages of pregnancy. Healthcare professionals are recognised as the most important influencers of vaccine uptake, being well placed to recommend vaccination and directly address safety concerns.

CONCLUSIONS

Despite data supporting the value of influenza vaccination during pregnancy, vaccine uptake remains low globally. Low uptake appears to be largely due to ineffective communication with pregnant women about the risks and benefits of influenza vaccination. A graphical abstract is available online.

Safety, equity and monitoring: a review of the gaps in maternal vaccination strategies for Aboriginal and Torres Strait Islander women

Influenza and pertussis infections are disproportionately higher among Aboriginal and Torres Strait Islander women and their infants compared to other Australians. These infections are potentially preventable through vaccination in pregnancy; however, there is a lack of systematic monitoring and therefore knowledge of vaccine uptake, safety and effectiveness in Australia, and specifically among Aboriginal and Torres Strait Islander women. The limited data available suggest there is a lower uptake of maternal vaccination among Aboriginal and Torres Strait Islander women compared to non-Aboriginal and Torres Strait Islander women, and this review seeks to explore potential reasons and the knowledge gaps in this regard. Other key gaps include the equitable access to quality antenatal care for Aboriginal and Torres Strait Islander women; and pregnancy loss <20 weeks gestation. Furthermore, our review highlights the importance of addressing these gaps in maternal vaccination strategies in partnership with Aboriginal and Torres Strait Islander peoples.