Influenza and Tdap Vaccination Coverage Among Pregnant Women - United States, April 2020

Effectiveness of cocoon strategy vaccination on prevention of influenza-like illness in young infants

During the initial half-year of their existence, infants cannot receive the influenza vaccine, yet they face the greatest susceptibility to severe influenza complications. In this study, we seek to determine whether influenza vaccination of maternal and household contacts is associated with a reduced risk of influenza-like illness (ILI) and severe acute respiratory infection (SARI) in infants. This work was prospectively conducted during the influenza season. A total of 206 infants were included in this study. The percentage of infants with only the mother vaccinated is 12.6% (n:26), and the percent of infants with all household contacts vaccinated is 16% (n:33). Among the infants with only the mother vaccinated, the effectiveness of influenza vaccine is estimated as 35.3% for ILI and 41.3% for SARI. Among infants with all household contacts vaccinated, the effectiveness is estimated as 48.9% for ILI and 76.9% for SARI. Based on the results of multivariate logistic regression analysis, all-household vaccination is a protective factor against SARI (OR: 0.07 95% CI [0.01-0.56]), household size (OR: 1.75, 95% CI [1.24-2.48]) and presence of secondhand smoke (OR: 2.2, 95% CI [1.12-4.45]) significant risk factors for SARI in infants. The mother alone being vaccinated is not a statistically significant protective factor against ILI (OR: 0.46, 95% CI [0.19-1.18]) or SARI (OR: 0.3, 95% CI [0.11-1.21]). Along with the obtained results and analysis, this study provides clear evidence that influenza vaccination of all household contacts of infants aged 0-6 months is significantly associated with protecting infants from both ILI and SARI.

Vaccination coverage during pregnancy and factors associated with refusal of recommended vaccinations: An Italian cross sectional study

Background

The vaccines recommended during pregnancy are the Tdap, the influenza vaccine, and, during the SARS-CoV-2 pandemic, the vaccine against COVID-19. This survey aimed at determining vaccination coverage among pregnant women and adverse events, reasons for vaccine refusal, and factors associated with vaccine uptake.

Methods

A single-center cross-sectional study was conducted on women who delivered between March and April 2022 at Careggi University Hospital in Florence, Italy. Information on the vaccinations (Tdap, influenza and COVID-19) received during pregnancy were collected through in-person interviews.

Results

Among 307 enrolled women (response rate 99 % on a study population of 310 eligible women), 74 % of patients were vaccinated with Tdap, 82 % against COVID-19, and only 33 % against influenza. Vaccination coverage for Tdap and COVID-19 was significantly higher among Italian than foreign patients (80 % vs 51 %, p < 0.001 and 86 % vs 69 %, p = 0.002, respectively), and for Tdap was higher among patients followed in the private vs public care setting. The main reasons behind refusal of vaccinations were low risk perception of influenza (41 %), insufficient information received from the prenatal care provider regarding the Tdap (35 %), and, for the COVID-19, fear of vaccine side effects (64 %), and concerns about effects on the fetus (70 %).

Conclusions

Adherence to the influenza vaccine was low because of reduced perception of the disease risks. The difference in vaccination coverage between Italians and foreigners is an example of healthcare disparity. Better information provided to patients about vaccines' efficacy and safety is advisable to increase acceptance of recommended vaccines.

Routine Maternal Vaccine Uptake during the COVID-19 Pandemic

OBJECTIVE

 This study examines the impact of the coronavirus disease 2019 (COVID-19) pandemic on influenza and tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine uptake in a pregnant, low-income population.

STUDY DESIGN

 This retrospective cohort study included women initiating prenatal care before (May-November 2019) or during the COVID-19 pandemic (May-November 2020) at two large Medicaid clinics. All patients entered prenatal care before 20 weeks and delivered full-term. Medical records were reviewed for vaccine uptake and demographic data. Multivariate logistic regression analysis was used to compare vaccination rates prior to and during the COVID-19 pandemic. Additional analysis was performed to identify association of demographic factors with vaccine uptake. IRB approval was obtained for this study.

RESULTS

 A total of 939 patients met inclusion criteria, with 462 initiating care prior to and 477 initiating care during the COVID-19 pandemic. Influenza vaccination uptake was 78% (362/462) in the prepandemic group, significantly decreasing to 61% (291/477) in the pandemic group (p <0.01, odds ratio [OR] = 0.38, confidence interval [CI]: 0.26-0.53). Tdap vaccination uptake was 85% (392/462) in the prepandemic group, significantly decreasing to 76% (361/477) in the pandemic group (p <0.01, OR = 0.56, CI: 0.40-0.79). The decrease in influenza vaccine uptake was most significant in non-Hispanic Black patients, decreasing from 64% (73/114) in the prepandemic group to 35% (35/101) in the pandemic group (p <0.01, OR = 0.30, CI: 0.17-0.52), while there was no significant difference in age or parity in relation to vaccination status.

CONCLUSION

 Routine vaccination uptake significantly decreased during the COVID-19 pandemic in a low-income population of pregnant women, with decrease more pronounced on influenza vaccine than on Tdap vaccine uptake, especially in non-Hispanic Black patients.

KEY POINTS

· Influenza and Tdap vaccination uptake during pregnancy has decreased during the COVID-19 pandemic.. · Influenza vaccine uptake decreased more than Tdap in pregnancy during the COVID-19 pandemic.. · The greatest decrease was seen in influenza vaccine uptake in non-Hispanic Black patients..

Routine Vaccination During Pregnancy Among People Living With HIV in the United States

Importance

Pregnancy represents a window of opportunity for vaccination due to established maternal and fetal benefits of vaccination. Little is known about receipt of routinely recommended vaccines in pregnancy, specifically tetanus, diphtheria, plus acellular pertussis (Tdap) and influenza, among pregnant people living with HIV (PLHIV).

Objective

To estimate prevalence of vaccination receipt among pregnant people with HIV (PLHIV) and identify demographic and clinical characteristics associated with vaccination.

Design, Setting, and Participants

This multicenter cohort study included women participating in Women's Health Study (WHS) of the Surveillance Monitoring for ART Toxicities (SMARTT) Study of the Pediatric HIV/AIDS Cohort Study. The network has been enrolling pregnant PLHIV at 22 US sites since 2007. Participants for this study enrolled between December 2017 and July 2019. Data analysis was conducted from October 2021 to March 2022.

Exposure

Data on vaccination in pregnancy were collected through medical record abstraction.

Main Outcomes and Measures

Vaccination receipt was defined as Tdap vaccination received at less than 36 weeks' gestation and influenza vaccination at any gestational age, based on current guidelines. Log-binomial and modified Poisson regression models with generalized estimating equations were fit to identify factors associated with successful receipt of (1) Tdap, (2) influenza, and (3) both vaccinations.

Results

A total of 310 pregnancies among 278 people participating in the WHS were included (mean [SD] age, 29.5 [6.1] years; 220 [71%] Black, 77 [25%] Hispanic, and 77 [25%] race and ethnicity other than Black; 64 [21%] with perinatally acquired HIV). Less than one-third of pregnancies were vaccinated as recommended (Tdap, 32.6% [95% CI, 27.4%-38.1%]; influenza, 31.6% [95% CI, 26.5%-37.1%]; both, 22.6% [95% CI, 18.0%-27.6%]). People living with perinatally acquired HIV, those who did not identify as Black, or those who were multiparous had adjusted risk ratios (aRRs) less than 1, while older PLHIV had aRRs greater than 1, but these differences did not reach statistical significance (perinatally acquired HIV: adjusted risk ratio [aRR], 0.46; 95% CI, 0.21-1.02; race other than Black: aRR, 0.53; 95% CI, 0.26-1.08; multiparous: aRR, 0.59; 95% CI, 0.35-1.00; age 24-29 years: aRR, 2.03; 95% CI, 0.92-4.48).

Conclusions and Relevance

In this diverse, multicenter cohort of pregnant PLHIV, receipt of recommended vaccinations was low. Identifying and addressing barriers to vaccination receipt is urgently needed for pregnant people with HIV.

RSV Vaccination Intention Among People Who Are or Plan to Become Pregnant

OBJECTIVES

Respiratory syncytial virus (RSV) is a common pediatric infection, with young infants being at the highest risk of hospitalization and long-term sequela. New preventive agents have been recommended to prevent severe RSV illness in infants, including a vaccine administered during pregnancy. The current rates of recommended vaccination in pregnancy are suboptimal. Our objective was to characterize interest in RSV vaccination during pregnancy among people across the United States who were pregnant or planning to become pregnant.

METHODS

In March 2023, we conducted a national cross-sectional online survey of individuals 18 to 45 years old who were currently pregnant or trying to become pregnant on their perceptions of RSV-related illness and intentions to get vaccinated against RSV. We performed logistic regression analyses to determine the odds and predicted proportions of the likelihood of RSV vaccination during pregnancy, controlling for sociodemographic factors.

RESULTS

Of 1619 completed surveys, 1528 were analyzed. 54% of respondents indicated that they were "very likely" to get vaccinated against RSV during pregnancy. The perception of RSV as a serious illness was the strongest predictor of vaccination likelihood. In the full regression model, predicted proportions of "very likely" to vaccinate against RSV followed a similar pattern (63% if RSV infection was perceived as serious and likely, 55% if serious and unlikely, 35% if not serious; P < .001).

CONCLUSIONS

Raising awareness of RSV infection as likely and potentially serious for infants may be an influential component of targeted communications that promote RSV vaccine uptake during pregnancy.

Assessing the Impact of the COVID-19 Pandemic on Pregnant Women's Attitudes towards Childhood Vaccinations: A Cross-Sectional Study

The COVID-19 pandemic has globally disrupted immunisation practices, impacting vulnerable populations such as pregnant women (PW), who harbour concerns about future children's immunisations. This study aimed to assess the pandemic's impact on PW's attitudes towards childhood vaccinations. During three consecutive flu seasons from October 2019 to January 2022, a cross-sectional study was conducted in a large Italian teaching hospital using a questionnaire. The chi-square test was performed to compare each season. Across the 2019-2020 to 2021-2022 seasons, course attendance by PW surged from 105 to 340. Significant shifts in vaccination intentions were noted, including a 7.5% decrease in measles vaccination intent (p = 0.02) and a 10% decrease in that of pertussis (p = 0.004) from 2019-2020 to 2020-2021. While perceived contagion risk decreased, disease severity perceptions increased, with few significant differences. A statistically significant reduction was noted in the proportion of participants suspecting economic motives behind NHS workers' promotion of childhood vaccinations. Furthermore, the pandemic period saw an increase in the perceived utility of non-institutional websites and the advice of physicians outside the NHS. These findings will help develop evidence-based, tailored interventions and communication strategies to address vaccine hesitancy and ensure optimal vaccination coverage among children born during and after the pandemic.

Maternal Vaccination in Pregnancy: An Assessment of Influenza, Pertussis, and COVID-19 Vaccination Rates in Cracow, Poland

BACKGROUND Maternal vaccination during pregnancy reduces the risk of severe course and complications from infections both for the mother and her child. As information regarding immunization status of pregnant women with recommended vaccines in Poland is scarce, this questionnaire-based study aimed to identify influenza, pertussis (whooping cough), and COVID-19 vaccination in 205 pregnant women in Cracow, Poland, between February and April 2023. Another objective was to assess whether any of the maternal factors might influence women's decision to inoculate during pregnancy. MATERIAL AND METHODS An anonymous and self-reported questionnaire developed specifically for this study was disseminated among postpartum women, who gave birth and were hospitalized at the Department of Obstetrics and Perinatology of the University Hospital in Cracow, Poland, between February and April 2023. Study participants were asked about their basic sociodemographic and obstetric data, as well as their immunization status regarding influenza, pertussis, and COVID-19 during their most recent pregnancy. RESULTS Only 12.2% and 23.4% of study participants received influenza and pertussis vaccinations, respectively, during pregnancy, while 61.5% of pregnant women reported vaccination with at least 2 doses of the mRNA COVID-19 vaccine. Features including type of occupation, place of residence, gravidity, and parity were statistically significant (P.

The impact of maternal pertussis vaccination recommendation on infant pertussis incidence and mortality in the USA: an interrupted time series analysis

BACKGROUND

Pertussis is a contagious respiratory disease. Maternal tetanus-diphtheria-acellular pertussis vaccination during pregnancy has been recommended by the United States Centres for Disease Control (US CDC) Advisory Committee on Immunization Practices (ACIP) for unvaccinated pregnant women since October 2011 to prevent infection among infants; in 2012, ACIP extended this recommendation to every pregnancy, regardless of previous vaccination status. The population-level effect of these recommendations on infant pertussis is unknown. This study aimed to examine the impact of the 2011/2012 ACIP pertussis recommendation on pertussis incidence and mortality among US infants.

METHODS

We used monthly data on pertussis deaths among infants aged <1 year between January 2005 and December 2017 in the CDC Death Data and yearly infant pertussis incidence data from the CDC National Notifiable Disease Surveillance System to perform an interrupted time series analysis, accounting for the passage of the Affordable Care Act.

RESULTS

This study included 156 months of data. A potential decline in trend in infant pertussis incidence was noted during the post-recommendations period. No appreciable differences in trend were found in population-level infant pertussis mortality after the guideline changes in both adjusted and unadjusted models. Results were similar for all mortality sensitivity analyses.

CONCLUSIONS

The 2011/2012 ACIP maternal pertussis vaccination recommendations were not associated with a population-level change in the trend in mortality, but were potentially associated with a decrease in incidence in the USA between 2005 and 2017.

Influenza vaccine during pregnancy, recommendations from healthcare providers, and race/ethnicity in the United States

OBJECTIVES

We examined racial/ethnic differences in the association between influenza vaccine recommendations from healthcare providers and maternal vaccination uptake.

METHODS

This cross-sectional study examined data from the Pregnancy Risk Assessment Monitoring System. We categorized respondents as non-Hispanic (NH) Whites, NH-Blacks, NH-Asians, American Indians/Alaska Natives, NH Other non-Whites, and Hispanics. We conducted multivariable logistical regression models to evaluate adjusted odds ratios (AOR) and 95% confidence intervals (CI). Covariates included maternal age, marital status, education, insurance status before pregnancy, the number of previous live births, the number of prenatal care visits, and smoking status during pregnancy.

RESULTS

The prevalences of receiving influenza vaccine recommendations from healthcare providers and maternal vaccine were 80.01% and 50.42%, respectively. NH-Blacks are less likely to receive provider recommendations (AOR = 0.82; 95%CI 0.77-0.87) and be vaccinated (AOR = 0.76; 95%CI 0.72-0.80) than NH-Whites. Receiving provider recommendations was significantly associated with increased maternal influenza vaccine uptake (AOR = 15.50; 95% CI 14.51-16.55). The associations were significant for all racial/ethnic groups, with the highest among NH-Asians (AOR = 22.04; 95% CI 17.88-27.16) and the lowest among NH Other non-Whites (AOR = 11.07; 95% CI 8.25-14.86). Within NH-Asians, effectiveness among Chinese was highest (AOR = 29.39; 95% CI 18.10-47.71).

CONCLUSIONS

Racial/ethnic disparities in maternal influenza vaccine uptake and receiving vaccine recommendations from healthcare providers persisted. Further studies on the racial/ethnic disparities in maternal vaccination were warranted and tailored strategies are required to reduce this health disparity.

Maternal Vaccine Effectiveness Against Influenza-Associated Hospitalizations and Emergency Department Visits in Infants

Importance

Influenza virus infection during pregnancy is associated with severe maternal disease and may be associated with adverse birth outcomes. Inactivated influenza vaccine during pregnancy is safe and effective and can protect young infants, but recent evidence, particularly after the 2009 novel influenza A (H1N1) pandemic, is limited.

Objective

To evaluate the effectiveness of influenza vaccination during pregnancy against laboratory-confirmed influenza-associated hospitalizations and emergency department (ED) visits in infants younger than 6 months.

Design, Setting, and Participants

This was a prospective, test-negative case-control study using data from the New Vaccine Surveillance Network from the 2016 to 2017 through 2019 to 2020 influenza seasons. Infants younger than 6 months with an ED visit or hospitalization for acute respiratory illness were included from 7 pediatric medical institutions in US cities. Control infants with an influenza-negative molecular test were included for comparison. Data were analyzed from June 2022 to September 2023.

Exposure

Maternal influenza vaccination during pregnancy.

Main Outcomes and Measures

We estimated maternal vaccine effectiveness against hospitalizations or ED visits in infants younger than 6 months, those younger than 3 months, and by trimester of vaccination. Maternal vaccination status was determined using immunization information systems, medical records, or self-report. Vaccine effectiveness was estimated by comparing the odds of maternal influenza vaccination 14 days or more before delivery in infants with influenza vs those without.

Results

Of 3764 infants (223 with influenza and 3541 control infants), 2007 (53%) were born to mothers who were vaccinated during pregnancy. Overall vaccine effectiveness in infants was 34% (95% CI, 12 to 50), 39% (95% CI, 12 to 58) against influenza-associated hospitalizations, and 19% (95% CI, -24 to 48) against ED visits. Among infants younger than 3 months, effectiveness was 53% (95% CI, 30 to 68). Effectiveness was 52% (95% CI, 30 to 68) among infants with mothers who were vaccinated during the third trimester and 17% (95% CI, -15 to 40) among those with mothers who were vaccinated during the first or second trimesters.

Conclusions and Relevance

Maternal vaccination was associated with reduced odds of influenza-associated hospitalizations and ED visits in infants younger than 6 months. Effectiveness was greatest among infants younger than 3 months, for those born to mothers vaccinated during the third trimester, and against influenza-associated hospitalizations.

A narrative review of COVID-19 vaccination in pregnancy and breastfeeding

The Coronavirus pandemic has affected millions of people due to the spread of the Severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) virus. Pregnant individuals and infants are most vulnerable given the increased risk of developing severe complications from SARS-CoV-2 infection. Recently, COVID-19 vaccination is recommended for pregnant women and infants starting at 6 months of age to prevent disease contraction and minimize disease severity. We conducted a review of the literature on COVID-19 vaccination to discuss vaccine safety and efficacy, immunity after maternal vaccination, transplacental transfer and persistence of antibodies, and public health implications. Current evidence supports the safety and efficacy of vaccination during pregnancy. Maternal vaccination provides greater antibody persistence in infants compared to immunity from natural infection. Furthermore, vaccination has demonstrated an increased rate of passive antibody transfer through the placenta and breast milk. Public health interventions are important in achieving herd immunity and ultimately ending the pandemic. IMPACT: This article highlights the benefits of COVID-19 vaccination during pregnancy with a review of the data describing safety and efficacy, passive and active immunity after maternal immunization, trans-placental transfer and persistence of protective antibodies, and public health implications. With this information, healthcare providers can provide up-to-date knowledge to their pregnant patients to help them form an informed decision on vaccination and combat vaccine hesitancy.

Maternal Tdap and influenza vaccination uptake 2017-2021 in the United States: Implications for maternal RSV vaccine uptake in the future

BACKGROUND

Assessment of maternal vaccine coverage is important for understanding and quantifying the impact of currently recommended vaccines as well as modeling the potential impact of future vaccines. However, existing data lack detail regarding uptake according to week of gestational age (wGA). Such granularity is valuable for more accurate estimation of vaccine impact.

OBJECTIVE

To summarize contemporary maternal Tdap vaccination uptake, overall, yearly, and by wGA, and maternal influenza vaccination uptake, overall, by influenza observation year, immunization month, and delivery month, in the US.

METHODS

Female patients 18-49 years of age with a pregnancy resulting in a live born infant (i.e., delivery) between 2017 and 2021 were selected from the Optum electronic health records (EHRs) database. Recently published gestational age algorithms were utilized to estimate wGA.

RESULTS

Of 1,021,260 deliveries among 886,660 women between 2017-2021, 55.1% had Tdap vaccination during pregnancy; vaccine coverage varied slightly by year (2017: 56.6%; 2018: 55.2%; 2019: 55.2%; 2020: 54.7%; 2021: 52.1%). Most (64.4%) maternal Tdap vaccinations occurred 27-32 wGA; 79.5% occurred during the entire 10-week recommended vaccination window (27-36 wGA). In the evaluation of influenza vaccination uptake (n=798,113 deliveries; 714,841 women), 33.5% of deliveries had influenza vaccination during influenza observation years 2017-2021, most (73.0%) of which occurred during influenza peak activity months (October-January) with approximately one-quarter (27.0%) of vaccinations having occurred during the off-peak months, mostly in September.

CONCLUSIONS

In this large contemporary analysis of EHR data, uptake of Tdap vaccination during pregnancy was consistent with previously published estimates; notably, most vaccination occurred early in the recommended 27-36 wGA window. Maternal influenza vaccination uptake largely correlated with peak influenza activity months and not gestational age. These study findings may have important implications for estimating the potential uptake and impact of future maternal vaccines.

Knowledge, attitudes, and practices (KAP) toward seasonal influenza vaccine among college students under the COVID-19 pandemic in South China

BACKGROUND

The control measures of the coronavirus disease 2019 (COVID-19) pandemic had influenced the activity of the influenza virus, and we were wondering the knowledge, attitudes, and practices (KAP) toward seasonal influenza vaccine among college students were having at the context of the COVID-19 pandemic.

METHODS

Online questionnaire survey of the college students was conducted and the data was collected anonymously, cross-sectional study were used to describe the distribution of the KAP.

RESULTS

There were 815 respondents in our study. Most participants have a high recognition of the effectiveness and safety of the influenza vaccine. However, a low awareness rate of influenza vaccine knowledge and vaccination rate (18%) against influenza was observed among college students. The education level and major would have a higher weight on the influence of KAP among the college students. Binary logistic regression analysis showed that the sex (OR = 2.163, p < .001), age (OR = 2.242, p < .001), heard of the influenza vaccine (OR = 2.655, p = .014), and "How necessary do you think vaccinating every year is?" (OR = 3.947, p < .001) of the college students were the main factors that affect the KAP on influenza vaccination.

CONCLUSIONS

Our study provided an insight into the KAP of influenza vaccine among college students in South China. The vaccination rate and acceptability of influenza vaccine in college students are higher than that in the whole population.

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.

Pertussis Non-Vaccination During Pregnancy Despite Advice From Prenatal Care Providers

OBJECTIVE

The purpose of this study was to measure the proportion of non-vaccination for pertussis in mothers in Canada who had been advised by their prenatal care provider to get vaccinated, and to identify sociodemographic factors and beliefs associated with non-vaccination.

METHODS

The Survey on Vaccination during Pregnancy (part of childhood National Immunization Coverage Survey) included biological mothers of children born from September 2018 to March 2019. This analysis was restricted to 2657 mothers who had been advised by their prenatal care provider to get vaccinated against pertussis during pregnancy and knew whether or not they had been vaccinated.

RESULTS

Of those who had been advised to get vaccinated against pertussis, 21% were not. This rate varied across provinces and territories, ranging from 9% in Prince Edward Island to 32% in Newfoundland and Labrador. Factors independently associated with pertussis non-vaccination included lower household income, having had past live births, and having received prenatal care from an obstetrician-gynecologist or a midwife compared to a family doctor. The risk of pertussis non-vaccination despite prenatal care advice was higher for those who disagreed that the baby would be at greater risk of pertussis if the mother did not get vaccinated. It was also higher for those who disagreed with statements regarding perceived benefits of vaccination. Conversely, disagreement with statements on perceived barriers was negatively associated with pertussis non-vaccination.

CONCLUSION

These findings highlight the underlying factors associated with non-vaccination against pertussis despite prenatal care provider recommendation. Some inaccurate beliefs about pertussis and vaccination during pregnancy persist, leading to non-vaccination.

Maternal pertussis vaccination behavior: Psychosocial, attitudinal and organizational factors

BACKGROUND

In December 2019, the maternal pertussis vaccination (MPV) became part of the Dutch National Immunization Program. This study aims to study MPV behavior and associated psychosocial, attitudinal and organizational factors of pertussis vaccination behavior during pregnancy in the Netherlands.

METHODS

We conducted a cross-sectional survey among pregnant women and recent mothers, up to six months post-partum. The primary outcome measure of this study was MPV behavior. Associations between psychosocial, attitudinal and organizational factors and MPV behavior were assessed using univariate and multivariate binary logistic regression analysis.

RESULTS

In total 1348 participants filled out the questionnaire, including 1282 (95.1%) MPV acceptors and 66 (4.9%) MPV refusers. The most important factors associated with MPV behavior were: attitude (aOR: 10.19; 95%CI: 4.30-24.16), outcome expectations (aOR: 8.94; 95%CI: 3.60-22.21), omission bias (aOR: 0.11; 95%CI: 0.02-0.59) and physical accessibility (aOR: 7.44; 95%CI: 3.37-16.46).

CONCLUSION

Pregnant women make their decision about the MPV primarily based on attitudinal and psychosocial factors, such as outcome expectations and attitude. A combination and variation of different messages, about the advantages (effectiveness) and disadvantages (side effects) of maternal vaccination, can be used in reaching pregnant women with a positive and negative attitude about the MPV. In addition, strategies to increase MPV uptake should not only focus on providing information, but also decrease experienced practical barriers, such as poor physical accessibility, in people that are intended to receive the MPV but are not getting vaccinated.

Attitudes Toward COVID-19 Vaccination Among Pregnant Persons in Urban Hospital-Affiliated Practices: Exploring Themes in Vaccine Hesitancy

OBJECTIVE

To explore beliefs and attitudes toward the COVID-19 vaccine among vaccinated and unvaccinated pregnant persons in order to identify reasons for both vaccine hesitancy and vaccine uptake.

METHODS

From June-August 2021, we conducted a qualitative study consisting of semi-structured interviews with pregnant persons (n = 30). Participants were recruited from university-owned obstetric practices during prenatal and ultrasound appointments. Interviews were audio recorded and transcribed; transcripts were coded and analyzed to identify themes and subthemes.

RESULTS

Of the participants, one-third (n = 10) had received the COVID-19 vaccine, while two-thirds (n = 20) were unvaccinated. Primary themes for unvaccinated participants were concern about the paucity of research on the vaccine in pregnancy and potential impact of the vaccine on both fetal development and maternal health. For vaccinated participants, main themes included potential maternal and fetal protection from COVID-19 and anticipated health complications from contracting COVID-19 as their motivations to get vaccinated. While most participants cited healthcare providers as the most trusted source of vaccine information, a majority reported that the internet was their primary source of vaccine information. Many participants wanted to learn more about the COVID-19 vaccine from their obstetric providers, and notably, most vaccinated participants reported the importance of their obstetrician in their vaccine decision-making process.

CONCLUSIONS

COVID-19 vaccine hesitancy is prevalent among pregnant persons, with concerns for vaccine safety for their fetus, as well as for themselves, being common. Obstetric providers must therefore be prepared to address common concerns with patients during prenatal appointments, taking the time to actively recommend vaccination.

Association of Provider Recommendation and Receipt of Influenza Vaccine Among Pregnant Women by Race and Ethnicity

Background: All pregnant women and those who may become pregnant are recommended by the Advisory Committee on Immunization Practices to receive the flu vaccine to prevent severe illness in the woman and infant. Despite the increased risk for complications in this population, flu vaccine uptake in pregnant women was 68.1% in the 2020-2021 flu season, with disparities by race and ethnicity. We sought to describe associations between provider recommendation with flu vaccine uptake by race and ethnicity in Tennessee women with a recent live birth. Materials and Methods: Weighted analysis used data from the 2016 to 2020 Tennessee Pregnancy Risk Assessment Monitoring System complex survey analysis procedures. Uptake was measured as receipt of flu vaccine in the 12 months before the most recent live birth, and positive recall of receiving provider advice to get the shot was the independent variable; for both we estimated 5-year averages stratified by race/ethnicity. Differences were assessed using chi-square tests. We modeled receipt of flu vaccine and estimated marginal predicted prevalence ratios (PRs); stratified models by race/ethnicity were constructed to estimate unadjusted and adjusted PRs. Results: The 5-year average for vaccine uptake before or during pregnancy was 56.7% but varied by race and ethnicity. Stratified bivariate analyses yielded different magnitudes of association by race/ethnicity between provider recommendation and flu vaccine receipt. After adjustment for payment source at delivery, marital status, age group, urbanicity, and maternal education, receiving a provider recommendation was strongly associated with flu vaccine uptake for all stratified models of pregnant women included in the study. The effect size was of a larger magnitude among non-Hispanic Black women, a population with a lower vaccine uptake. Conclusions: Given the association between provider recommendation and vaccine uptake in all groups, attention should be focused on increasing rates of provider recommendation.

Influenza, Tdap, and COVID-19 Vaccination Coverage and Hesitancy Among Pregnant Women - United States, April 2023

Influenza, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap), and COVID-19 vaccines can reduce the risk for influenza, pertussis, and COVID-19 among pregnant women and their infants. To assess influenza, Tdap, and COVID-19 vaccination coverage among women pregnant during the 2022-23 influenza season, CDC analyzed data from an Internet panel survey conducted during March 28-April 16, 2023. Among 1,814 survey respondents who were pregnant at any time during October 2022-January 2023, 47.2% reported receiving influenza vaccine before or during their pregnancy. Among 776 respondents with a live birth by their survey date, 55.4% reported receiving Tdap vaccine during pregnancy. Among 1,252 women pregnant at the time of the survey, 27.3% reported receipt of a COVID-19 bivalent booster dose before or during the current pregnancy. Data from the same questions included in surveys conducted during influenza seasons 2019-20 through 2022-23 show that the proportion of pregnant women who reported being very hesitant about influenza and Tdap vaccinations during pregnancy increased from 2019-20 to 2022-23. Pregnant women who received a provider recommendation for vaccination were less hesitant about influenza and Tdap vaccines. Promotion of efforts to improve vaccination coverage among pregnant women, such as provider recommendation for vaccination and informative conversations with patients to address vaccine hesitancy, might reduce vaccine hesitancy and increase coverage with these important vaccines to protect mothers and their infants against severe respiratory diseases.

Risk of Miscarriage in Relation to Seasonal Influenza Vaccination Before or During Pregnancy

OBJECTIVE

To evaluate the association between seasonal influenza vaccination and miscarriage using data from an ongoing, prospective cohort study.

METHODS

We analyzed 2013-2022 data from PRESTO (Pregnancy Study Online), a prospective prepregnancy cohort study of female pregnancy planners and their male partners in the United States and Canada. Female participants completed a baseline questionnaire and then follow-up questionnaires every 8 weeks until pregnancy, during early and late pregnancy, and during the postpartum period. Vaccine information was self-reported on all questionnaires. Miscarriage was identified from self-reported information during follow-up. Male partners were invited to complete a baseline questionnaire only. We used Cox proportional hazard models to estimate the hazard ratio (HR) and 95% CI for the association between vaccination less than 3 months before pregnancy detection through the 19th week of pregnancy and miscarriage, with gestational weeks as the time scale. We modeled vaccination as a time-varying exposure and used propensity-score fine stratification to control for confounding from seasonal and female partner factors.

RESULTS

Of 6,946 pregnancies, 23.3% of female partners reported exposure to influenza vaccine before or during pregnancy: 3.2% during pregnancy (gestational age 4-19 weeks) and 20.1% during the 3 months before pregnancy detection. The miscarriage rate was 16.2% in unvaccinated and 17.0% among vaccinated participants. Compared with no vaccine exposure, influenza vaccination was not associated with increased rate of miscarriage when administered before (HR 0.99, 95% CI 0.81-1.20) or during (HR 0.83, 95% CI 0.47-1.47) pregnancy. Of the 1,135 couples with male partner vaccination data available, 10.8% reported vaccination less than 3 months before pregnancy. The HR for the association between male partner vaccination and miscarriage was 1.17 (95% CI 0.73-1.90).

CONCLUSION

Influenza vaccination before or during pregnancy was not associated with miscarriage.

Resources available for parent-provider vaccine communication in pregnancy in Canada: a scoping review

OBJECTIVE

Vaccination in pregnancy (VIP) is a protective measure for pregnant individuals and their babies. Healthcare provider's (HCP) recommendations are important in promoting VIP. However, a lack of strong recommendations and accessible resources to facilitate communication impact uptake. This study sought to determine the extent of and characterise the resources available for parent-provider vaccine communication in pregnancy in Canada using a behavioural theory-informed approach.

DESIGN

Scoping review.

METHODS

In accordance with the JBI methodology, nine disciplinary and interdisciplinary databases were searched, and a systematic grey literature search was conducted in March and January 2022, respectively. Eligible studies included resources available to HCPs practising in Canada when discussing VIP, and resources tailored to pregnant individuals. Two reviewers piloted a representative sample of published and grey literature using inclusion-exclusion criteria and the Authority, Accuracy, Coverage, Objectivity, Date, Significance guidelines (for grey literature only). Sixty-five published articles and 1079 grey reports were screened for eligibility, of which 19 articles and 166 reports were included, respectively.

RESULTS

From the 19 published literature articles and 166 grey literature reports, 95% were driven by the 'Knowledge' domain of the Theoretical Domains Framework, while n=34 (18%) addressed the 'Skills' domain. Other gaps included a lack of VIP-specific tools to address hesitancy and a lack of information on culturally safe counselling practices.

CONCLUSION

The study suggests a need for resources in Canada to improve VIP communication skills and improve access to vaccination information for HCPs and pregnant individuals. The absence of such resources may hinder VIP uptake.

A study of acceptance and hesitation factors towards tetanus, diphtheria, and acellular pertussis (Tdap) and influenza vaccines during pregnancy

Introduction

Vaccination of pregnant women with tetanus, diphtheria, and acellular pertussis (Tdap) and influenza vaccines is desirable to reduce neonatal and maternal morbidity and mortality. However, vaccine coverage rates and acceptance are frequently below recommended rates.

Objectives

To ascertain Tdap and influenza vaccine coverage rates in our population and to study the reasons behind sub-optimal rates.

Method

A survey was submitted to pregnant or in their puerperium women at the University Hospital of São Paulo University. Data were obtained during two consecutive influenza seasons (2017-2018), and vaccination was verified through vaccination chart checking. Respondents were classified according to their status as "Received Tdap" and "Didn't receive Tdap", and as "Know" or "Doesn't know" regarding their awareness of Tdap safety during pregnancy and protective effect on the newborn. Vaccine uptake and personal awareness of vaccination status were compared among these groups for Tdap and influenza vaccines.

Results

In a studied sample of 207 patients (representative of the whole), coverage rates for Tdap and influenza vaccines were respectively 85.5% and 95.2%. Additionally, 84.5% received both vaccines. There was no vaccine refusal for Tdap and only 0.5% for influenza. For either Tdap or influenza vaccines, the main reason for not vaccinating was a lack of knowledge/information. Factors associated with not vaccinating Tdap during pregnancy were lower number of prenatal visits, being unemployed or freelance worker, not being aware of vaccine safety or its benefits for the baby, not being oriented by the doctor to be vaccinated, not being aware of personal vaccination status, and not having been vaccinated for influenza.

Conclusion

While influenza vaccination coverage during pregnancy was ideal, Tdap rates were below recommended values. Significant factors associated with better coverage for Tdap during pregnancy included being employed and not being self-employed, (not yet reported in the Americas) and being aware of personal vaccination status.

Maternal vaccination: shaping the neonatal response to pertussis

Antepartum maternal vaccination can protect highly sensitive newborns before they are old enough to receive their own vaccines. Two vaccines are currently recommended during pregnancy: the flu vaccine and the Tdap vaccine against tetanus, diphtheria, and pertussis. Although there is strong evidence that maternal vaccination works to protect the offspring, limitations in the understanding of vaccines and of maternal transfer of immunity compound to obscure our understanding of how they work. Here we focus on the example of pertussis to explore the possible mechanisms involved in the transfer of protection to offspring and how these may impact the newborn's response to future exposure to pertussis. For example, Tdap vaccines induce pathogen specific antibodies, and those antibodies are known to be transferred from mother to the fetus in utero and to the newborn via milk. But antibodies alone have modest impact on pertussis disease, and even less effect on colonization/transmission. Maternal immune cells can also be transferred to offspring and may play a direct role in protection from disease and/or influence the developing neonatal immune system. However, some of the transferred immunity may also blunt the offspring's response to subsequent vaccination. In this review we will summarize the protection conferred to offspring by maternal vaccination against pertussis and the likely mechanisms by which protection is transferred, identifying the many knowledge gaps that limit our most effective application of this approach.

A Descriptive Study of Maternal Vaccination Uptake, Attitudes, and Beliefs in Pregnancy Among Persons Delivering at an Urban Safety Net Hospital

Objective

To estimate uptake of influenza, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap), and COVID-19 vaccines during pregnancy and describe vaccine attitudes and beliefs among predominantly racial and ethnic minority individuals delivering at a publicly funded hospital.

Methods

We collected survey and electronic medical record data for English-speaking postpartum individuals who delivered a live-born infant from July 7, 2022, through August 21, 2022, and agreed to participate in our study. The 58-item survey included questions about general vaccine attitudes and beliefs as well as vaccine-specific questions. We calculated rates of influenza, Tdap, and COVID-19 vaccinations and compared distributions of survey responses by number (no vaccines, one vaccine, or two or three of the recommended vaccines) and type of vaccines received during pregnancy.

Results

Of the 231 eligible individuals, 125 (54.1%) agreed to participate. Rates of influenza, Tdap, and COVID-19 vaccination were 18.4%, 48.0%, and 5.6% respectively. A total of 61 (48.8%) did not receive any recommended vaccines during pregnancy, 40 (32.0%) received one vaccine, and 24 (19.0%) received two or three vaccines. Approximately 66.1% of the no vaccine group, 81.6% of the one vaccine group, and 87.5% of the two or three vaccine group strongly agreed or agreed that they trusted the vaccine information provided by their obstetrician or midwife. While most (>69.2%) agreed that the vaccine-preventable diseases were dangerous for pregnant women, only 24.0%, 29.3%, and 40.3% agreed that they were worried about getting influenza, whooping cough, or COVID-19, respectively, while pregnant.

Discussion

Vaccine uptake in our population was low and may be due, in part, to low perceived susceptibility to vaccine-preventable diseases. Obstetricians and midwives were trusted sources of vaccine information, suggesting that enhanced communication strategies could be critical for addressing maternal vaccine hesitancy, particularly in communities of color justifiably affected by medical mistrust.

Vaccination against influenza in pregnant women in a maternity hospital in the Czech Republic in the season 2020-2021

OBJECTIVES

Pregnant women are among the priority groups to receive influenza vaccines in the Czech Republic since 2011, data on vaccination coverage are not yet available. The aim of the study was to determine the influenza vaccination coverage (IVC) and provide source data for further activities.

METHODS

A prospective observational study was performed in a large maternity hospital in Prague. The self-completed questionnaire was distributed to 5,475 pregnant women between September 1, 2020 and August 31, 2021. Questions included maternal sociodemographic characteristics, influenza vaccination status and sources of maternal vaccination recommendations during pregnancy.

RESULTS

A total of 4,617 completed questionnaires have been analysed. The median age of study participants (N = 4,592) was 33 years (range: 18-51 years). The majority (69.7%) of women had completed their university education, most women were childless (58.5%) or had one child (32.5%) before the start of the study. Less than 2% of women reported being vaccinated against influenza during their pregnancy (1.5%; 95% CI, 1.1-1.9%). Only 21% of women knew that it's possible to get vaccinated against influenza during pregnancy. Participants considered influenza vaccination in pregnancy as important (3.3%), useful (41.1%) and useless (44.4%). Out of 959 pregnant women who had information about influenza vaccination during pregnancy, only 6.9% were vaccinated, while among those who did not have this information, 0.1% were vaccinated during pregnancy (p < 0.001). The most frequent source of information was Internet, then media and a general practitioner.

CONCLUSIONS

The IVC during pregnancy in our study was extremely low. In order to improve IVC among pregnant women, it is necessary to increase awareness of recommendations and vaccination options among the public and professionals and incorporating vaccination recommendation in routine antenatal practice.

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.

Pregnancy vaccination predictive factors and uptake profiles among Italian women: A cross-sectional survey study on a large population

OBJECTIVES

To assess influenza and Tdap (tetanus, diphtheria, pertussis) vaccine coverage during pregnancy, explore key socioeconomic and maternity pathway-related predictors of vaccination, and detect specific patterns of vaccination uptake.

METHODS

The authors cross-sectionally analyzed self-reported data obtained from the systematic survey on the maternity pathways of Tuscany. They selected all pregnant women that completed from March 2019 to June 2022 the third-trimester questionnaire (n = 25 160), which included two dichotomous items on influenza and Tdap vaccination, as well as socioeconomic and pathway-related questions. Multilevel logistic models were performed to assess vaccination predictors and cluster analysis to identify vaccination patterns.

RESULTS

Vaccination coverage was higher for pertussis (56.5%) than for influenza (18.9%). The main predictors of vaccination were high socioeconomic status, attending private gynecologists, and receiving vaccine information. Three clusters were identified: cluster 1 included women receiving both Tdap and influenza vaccines; cluster 2 included women receiving no vaccinations; and cluster 3 included women receiving only the pertussis vaccine. Although women from cluster 3 were of middle to low education status, vaccine information was the main adherence determinant also in this group.

CONCLUSIONS

Health workers and policymakers should focus on groups of pregnant women less prone to vaccination to promote vaccination information and encourage wider uptake and coverage.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

STUDY REGISTRATION

ClinicalTrials.gov, NCT05040802.

COVID-19 vaccination recommendations and practices for women of reproductive age, U.S. Physicians, Fall 2021

Pregnant people with COVID-19 are at increased risk for severe illness and adverse pregnancy outcomes. COVID-19 vaccinations are safe and effective, including for pregnant and recently pregnant people. The objective of this analysis was to describe the extent to which primary care physicians across the United States report confidence in talking with female patients of reproductive age about COVID-19 vaccination, recommending COVID-19 vaccinations to pregnant patients, and offering COVID-19 vaccinations at their practices in fall 2021. We analyzed cross-sectional data from the Fall 2021 DocStyles survey, a web-based panel survey of U.S. primary healthcare providers (64% response rate). Family practitioners/internists, obstetrician-gynecologists, and pediatricians were asked about confidence in talking with female patients of reproductive age about COVID-19 vaccination, vaccination practices regarding pregnant patients, and offering COVID-19 vaccinations. We describe results overall and by select physician characteristics. Among 1501 respondents, most were family practitioners/internists (67%), 17% were obstetrician-gynecologists, and 17% were pediatricians. Overall, 63% were very confident talking with female patients of reproductive age about COVID-19 vaccination, 80% recommended pregnant patients get vaccinated as soon as possible, and 50% offered COVID-19 vaccinations at their current practice. Obstetrician-gynecologists were most confident in talking with female patients, but only one-third offered the vaccine at their practices. This analysis found that most physicians felt confident talking about COVID-19 vaccinations and recommended pregnant patients get vaccinated as soon as possible. Provider recommendation for vaccination remains a key strategy for achieving high vaccination coverage, and consistent recommendations may improve vaccine acceptance among pregnant and postpartum people.

Maternal Vaccination and Vaccine Hesitancy

The American College of Obstetrics and Gynecology recommends influenza vaccine annually, Tdap with each pregnancy, and COVID-19 vaccine for those not previously vaccinated or who are due for boosters. The influenza and COVID-19 vaccines are safe during pregnancy and are effective in reducing morbidity in both the pregnant person and infant. The Tdap vaccine is given primarily to protect the newborn from pertussis through transplacental antibody transfer. Methods to enhance vaccination rates include stocking and giving vaccines in the obstetric office, recommending eligible vaccines at each visit, and focusing on the health of the infant in conversations with patients.

US Infant Pertussis Incidence Trends Before and After Implementation of the Maternal Tetanus, Diphtheria, and Pertussis Vaccine

Importance

Infants younger than 1 year have the highest burden of pertussis morbidity and mortality. In 2011, the US introduced tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccination during pregnancy to protect infants before vaccinations begin.

Objective

To assess the association of maternal Tdap vaccination during pregnancy with the incidence of pertussis among infants in the US.

Design, Setting, and Participants

In this ecologic study, a time-trend analysis was performed of infant pertussis cases reported through the National Notifiable Diseases Surveillance System between January 1, 2000, and December 31, 2019, in the US. Statistical analysis was performed from April 1, 2020, to October 31, 2022.

Exposures

Maternal Tdap vaccination during pregnancy.

Main Outcomes and Measures

Pertussis incidence rates were calculated and compared between 2 periods-the pre-maternal Tdap vaccination period (2000-2010) and the post-maternal Tdap vaccination period (2012-2019)-for 2 age groups: infants younger than 2 months (target group of maternal vaccination) and infants aged 6 months to less than 12 months (comparison group). Incidence rate differences between the 2 age groups were modeled using weighted segmented linear regression. The slope difference between the 2 periods was estimated to assess the association of maternal Tdap vaccination with pertussis incidence among infants.

Results

A total of 57 460 pertussis cases were reported in infants younger than 1 year between 2000 and 2019; 19 322 cases (33.6%) were in infants younger than 2 months. During the pre-maternal Tdap vaccination period, annual pertussis incidence did not change among infants younger than 2 months (slope, 3.29 per 100 000 infants per year; P = .28) but increased slightly among infants aged 6 months to less than 12 months (slope, 2.10 per 100 000 infants per year; P = .01). There was no change in the difference in incidence between the 2 age groups (slope, 0.08 per 100 000 infants per year; P = .97) during the pre-maternal Tdap vaccination period overall. However, in the post-maternal Tdap vaccination period, incidence decreased among infants younger than 2 months (slope, -14.53 per 100 000 infants per year; P = .001) while remaining unchanged among infants aged 6 months to less than 12 months (slope, 1.42 per 100 000 infants per year; P = .29). The incidence rate difference between the 2 age groups significantly decreased during the post-maternal Tdap vaccination period (slope, -14.43 per 100 000 infants per year; P < .001). Pertussis incidence rate differences were significantly different between the pre-maternal and post-maternal Tdap vaccination periods (slope difference, -14.51 per 100 000 infants per year; P = .01).

Conclusions and Relevance

In this study, following maternal Tdap vaccine introduction, a sustained decrease in pertussis incidence was observed among infants younger than 2 months, narrowing the incidence gap with infants aged 6 months to less than 12 months. These findings suggest that maternal Tdap vaccination is associated with a reduction in pertussis burden in the target age group (<2 months) and that further increases in coverage may be associated with additional reductions in infant disease.

Acceptance of vaccination against pertussis, COVID-19 and influenza during pregnancy: a cross-sectional study

Background

This study aims to assess the uptake of maternal pertussis and COVID-19 vaccination and the intention towards accepting the maternal influenza vaccination. Insights into different socio-demographic factors related to maternal vaccination coverage might help to address vaccine acceptance and improve maternal vaccine uptake in the future.

Methods

We conducted a cross-sectional survey among pregnant women and recent mothers, up to 6 months post-partum. The primary outcome measures of this study were behaviour for maternal pertussis and COVID-19 vaccination, and maternal influenza vaccination intention. Associations between socio-demographic factors and maternal pertussis vaccination and maternal COVID-19 vaccination behaviour; and socio-demographic factors and maternal influenza vaccination intention were assessed using binary logistic regression analyses.

Results

In total 1361 respondents filled out the questionnaire. Almost all women (95%) were vaccinated against pertussis during pregnancy, while almost two-third were vaccinated against COVID-19 during pregnancy (58%) and almost one-third (28%) had a positive intention towards receiving the maternal influenza vaccination. Results show that young maternal age and low education level were associated with lower maternal vaccination acceptance.

Conclusion

Vaccination campaigns focusing on the severity of diseases that are prevented, are needed to increase maternal vaccine acceptance in younger and low-educated pregnant women. We expect that differences in vaccination coverage between the three maternal vaccinations might partly be explained by existing recommendations, campaigns and whether the vaccination is part of the national immunisation program.

The association between maternal influenza vaccination during pregnancy and adverse birth outcomes in the United States: Pregnancy risk Assessment Monitoring System (PRAMS)

OBJECTIVE

Influenza vaccination during pregnancy is highly recommended. We examined the association between maternal influenza vaccination and adverse birth outcomes.

METHODS

This cross-sectional study used data from the Pregnancy Risk Assessment Monitoring System (PRAMS) during 2012-2017. The primary exposure was the receipt of influenza vaccination during pregnancy. Low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA) were the primary outcomes. We conducted multivariable logistic regression models to estimate the adjusted odds ratios (AOR) and 95% confidence intervals (CI). Covariates used to adjust confounding included maternal age, marital status, education, race and ethnicity, insurance status before pregnancy, and smoking status. For a subgroup in 2012-2015, we analyzed the association between influenza vaccination in each trimester and adverse birth outcomes.

RESULTS

During 2012-2017, compared with unvaccinated women, women vaccinated during pregnancy had a lower risk of LBW and PTB. During 2012-2015, maternal influenza vaccination in the 1st and 3rd trimesters was associated with a reduced risk of LBW and PTB, and vaccination in the 3rd trimester had a greater protective effect than in the 1st trimester. Influenza vaccination was not associated with SGA regardless of trimester.

CONCLUSIONS

Our findings suggest that influenza vaccination during pregnancy is a safe and effective way to protect newborns.

Maternity care provider acceptance of a future Group B Streptococcus vaccine - A qualitative study in three countries

INTRODUCTION

There are vaccines in clinical trials that target the bacterium Group B Streptococcus (GBS). When approved, GBS vaccines will be intended for administration to pregnant women to prevent infection in their infants. The success of any vaccine will depend on its' uptake in the population. Experience with prior maternal vaccines, e.g. influenza, Tdap and COVID-19 vaccines, teaches us that acceptance of vaccines, especially if novel, is challenging for pregnant women, and that provider recommendation is a key driver of vaccine uptake.

METHODS

This study investigated attitudes of maternity care providers towards the introduction of a GBS vaccine in three countries (the United States (US), Ireland, and the Dominican Republic (DR)) with different GBS prevalence and prevention practices. Semi-structured interviews with maternity care providers were transcribed and coded for themes. The constant comparative method, and inductive theory building were used to develop conclusions.

RESULTS

Thirty-eight obstetricians, 18 general practitioners and 14 midwives participated. There was variability in provider attitudes towards a hypothetical GBS vaccine. Responses ranged from enthusiasm to doubts over the need for a vaccine. Attitudes were influenced by perceived additional benefits of a vaccine over current strategy and confidence in the safety of vaccines during pregnancy. Knowledge, experience and approaches to GBS prevention differed geographically and according to provider type, and influenced how participants assessed the risks and benefits of a GBS vaccine.

CONCLUSION

Maternity care providers are engaged in the topic of GBS management and there is opportunity to leverage attitudes and beliefs that will support a strong recommendation for a GBS vaccine. However, knowledge of GBS, and of the limitations of current prevention strategies vary among providers in different regions, and between different provider types. Targeted educational efforts with antenatal providers should focus on highlighting safety data the potential benefits of vaccination over current strategies.

Association Between Influenza Vaccination During Pregnancy and Infant Influenza Vaccination

OBJECTIVE

To examine the association between influenza vaccination during pregnancy and infant influenza vaccination.

METHODS

We conducted a retrospective analysis of individuals aged 15-49 years who were continually privately insured from August 2017 to May 2019 and had singleton live births between September 2017 and February 2018 and their infants. Influenza vaccination coverage was assessed for pregnant people during the 2017-2018 influenza season and for their infants during the 2018-2019 season using the 2017-2019 MarketScan data. Multivariate log-binomial regressions were conducted to examine the association between influenza vaccination during pregnancy and infant influenza vaccination.

RESULTS

Of the 34,919 pregnant people in this analysis, 14,168 (40.6%) received influenza vaccination during pregnancy. Of the infants born to people vaccinated during pregnancy, 90.0% received at least one dose of influenza vaccine during the 2018-2019 season and 75.5% received at least two doses. Of the infants born to those not vaccinated during pregnancy, 66.3% received at least one dose of influenza vaccine and 51.8% received at least two doses. At-least-one-dose coverage was 35.7% higher (adjusted risk ratio [aRR] 1.34, 95% CI 1.33-1.36) and at-least-two-dose coverage was 45.8% higher (aRR 1.43, 95% CI 1.41-1.46) for infants born to people who received influenza vaccination during pregnancy compared with infants born to people who did not.

CONCLUSION

Our results show a positive and statistically significant relationship between influenza vaccination during pregnancy and infant influenza vaccination status in their first season eligible for vaccination. Interventions to increase influenza vaccination coverage among pregnant people may also increase infant influenza vaccination coverage, offering greater protection against serious complications of influenza in both vulnerable populations.

Surveillance Systems for Monitoring Vaccination Coverage with Vaccines Recommended for Pregnant Women, United States

Pregnant women* and their infants are at increased risk for serious influenza, pertussis, and COVID-19-related complications, including preterm birth, low-birth weight, and maternal and fetal death. The advisory committee on immunization practices recommends pregnant women receive tetanus-toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine during pregnancy, and influenza and COVID-19 vaccines before or during pregnancy. Vaccination coverage estimates and factors associated with maternal vaccination are measured by various surveillance systems. The objective of this report is to provide a detailed overview of the following surveillance systems that can be used to assess coverage of vaccines recommended for pregnant women: Internet panel survey, National Health Interview Survey, National Immunization Survey-Adult COVID Module, Behavioral Risk Factor Surveillance System, Pregnancy Risk Assessment Monitoring System, Vaccine Safety Datalink, and MarketScan. Influenza, Tdap, and COVID-19 vaccination coverage estimates vary by data source, and select estimates are presented. Each surveillance system differs in the population of pregnant women, time period, geographic area for which estimates can be obtained, how vaccination status is determined, and data collected regarding vaccine-related knowledge, attitudes, behaviors, and barriers. Thus, multiple systems are useful for a more complete understanding of maternal vaccination. Ongoing surveillance from the various systems to obtain vaccination coverage and information regarding disparities and barriers related to vaccination are needed to guide program and policy improvements.

Tetanus, Diphtheria, and Acellular Pertussis Vaccination Coverage Among Publicly Insured Pregnant Women, U.S., 2016-2019

Introduction

Vaccination with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine during pregnancy is highly effective against Bordetella pertussis in young infants. We aimed to evaluate the uptake of maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination during the recommended gestation period of 27 through 36 weeks among women enrolled in a public medical insurance plan in the U.S.

Methods

In this analysis using Centers for Medicare and Medicaid Services insurance claims data, we identified women aged 15 through 49 years who delivered a live-born infant from 2016 through 2019. We identified claims for tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination to calculate the proportion of women who were vaccinated during Weeks 27 through 36 of gestation in each calendar year. We also assessed the average annual maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis coverage by age group, race and ethnicity, U.S. Census region of residence, and plan type. Data were analyzed in 2021.

Results

Among 4,318,823 deliveries, the 4-year national average for tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccination was 26%, improving from 22% in 2016 to 31% in 2019 (p<0.001). Within subgroups, the lowest 4-year average coverage was among women aged 15 through 18 years (22%); Black, non-Hispanic (23%) and Hispanic women (24%); those residing in the South (18%); those enrolled in a Children's Health Insurance Program plan (22%); and those covered by a fee-for-service plan (19%). Coverage increased across all subgroups from 2016 through 2019.

Conclusions

Although maternal tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis coverage among publicly insured women in the U.S. increased from 2016 through 2019, it remained considerably lower than estimated national coverage, with notable differences by race and ethnicity.

Maternal Tetanus Toxoid, Reduced Diphtheria Toxoid, and Acellular Pertussis Vaccination During Pregnancy: Impact on Infant Anti-Pertussis Antibody Concentrations by Maternal Pertussis Priming Series

BACKGROUND

Acellular pertussis (aP) vaccines replaced whole-cell pertussis (wP) vaccines for the US childhood primary series in 1997. As women primed with aP vaccines enter childbearing age, protection of infants through tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccination during pregnancy may be impacted.

METHODS

Term infants born to women vaccinated with Tdap during pregnancy were included. Geometric mean concentrations (GMCs) of pertussis-specific immunoglobulin G antibodies (international units per milliliter) in cord blood of infants born to women born after 1997 (aP-primed) were compared with those born to women born before 1992 (wP-primed).

RESULTS

253 and 506 infants born to aP- and wP-primed women, respectively, were included. Compared with wP-primed women, aP-primed women were younger, more likely to be Hispanic or non-Hispanic Black, and had lower-birthweight infants (P < .01 for all). Antibodies against pertussis toxin (PT) and filamentous hemagglutinin (FHA) were lower among infants born to aP-primed vs wP-primed women (PT, 17.3 vs 36.4; GMC ratio, .475; 95% confidence interval [CI], .408-.552 and FHA, 104.6 vs 121.4; GMC ratio, 0.861; 95% CI, .776-.958). No differences were observed for anti-fimbriae or anti-pertactin antibodies.

CONCLUSIONS

Transplacental anti-pertussis antibody concentrations in infants of women vaccinated with Tdap during pregnancy differed by type of childhood vaccine the women received. Notably, anti-PT antibody levels, considered most important in preventing severe infant disease, were lower in infants born to aP-primed vs wP-primed women. Maternal Tdap vaccination may confer less protection against pertussis in infants born to aP-primed vs those born to wP-primed women.

Maternal vaccination-current status, challenges, and opportunities

AIM

Maternal vaccination is a promising strategy for protecting pregnant women and newborns against severe infections. This review aims to describe the current status and challenges associated with maternal vaccination against seasonal influenza, tetanus-diphtheria-pertussis (Tdap/DTaP), and novel coronavirus disease of 2019 (COVID-19) in Japan and other countries, mainly the United States and the United Kingdom.

METHODS

A literature search was conducted in PubMed and other public websites (e.g., Centers for Disease Control and Prevention) to obtain information on maternal vaccination.

RESULTS

Inactivated vaccines are recommended for pregnant women by gynecologic societies in Japan, the United States, and the United Kingdom. Among pregnant Japanese women, the influenza and COVID-19 (two doses) vaccine coverage rates were 27.0%-53.5% (six studies) and 73.6% (one study), respectively; there are no studies on maternal vaccination with DTaP. Concerns regarding vaccine safety are a major barrier to maternal vaccination across countries. Maternal vaccination is effective in preventing severe disease in pregnant women and protecting infants aged <6 months, is generally safe, and does not increase the risk of adverse maternal and fetal outcomes. Providing accurate information regarding vaccination through healthcare providers and the government and government funding for vaccines may help improve maternal vaccination rates in Japan.

CONCLUSION

Current coverage for maternal vaccination is still low globally mainly because of vaccine hesitancy among pregnant women. The government, drug-regulatory authorities, and healthcare professionals must educate pregnant women about the effectiveness and safety of maternal vaccines and encourage vaccination when the benefits outweigh the risks.

Disparities in Prenatal Immunization Rates in Rural and Urban US Areas by Indicators of Access to Care

PURPOSE

To evaluate disparities in urban-rural immunization rates among pregnant women by indicators of access to health care.

METHODS

We analyzed Phase 8 (2016-2018) Pregnant Risk Assessment Monitoring System data for 82,603 respondents who recently gave birth to a live infant. Uptake of influenza (33 states) or Tdap (19 states) vaccines was compared for rural versus urban areas of participating states. We compared the prevalence of immunization for rural versus urban areas by indicators of health care access using average marginal predictive values from multivariable regression models.

FINDINGS

Although nearly half (48.2%) of pregnant women in rural areas relied on Medicaid to fund prenatal care, rural-residing women were less likely to live in a state offering full coverage under Medicaid to pregnant women than urban-residing women (93.9% vs 98.0%, respectively). Among states with Medicaid programs not offering full access for pregnant women, influenza immunization coverage was 12% lower (aPR 0.88; 95% CI 0.82, 0.94) and Tdap immunization coverage was 20% lower (aPR 0.80; 95% CI 0.68, 0.95) for rural versus urban areas. Uninsured women in rural areas were less likely to receive influenza or Tdap vaccine compared to uninsured women in urban areas (aPR 0.65; 95% CI 0.50, 0.85 and aPR 0.73; 95% CI 0.57, 0.95, respectively).

CONCLUSIONS

Pregnant women residing in rural areas more commonly rely on Medicaid to financially support prenatal care but are less likely to have expanded or full access to Medicaid coverage, potentially contributing to disparities vaccine uptake during pregnancy and increased rates of vaccine-preventable disease.

Protecting pregnant people & infants against influenza: A landscape review of influenza vaccine hesitancy during pregnancy and strategies for vaccine promotion

Before COVID-19, influenza vaccines were the most widely recommended vaccine during pregnancy worldwide. In response to immunization during pregnancy, maternal antibodies offer protection against potentially life-threatening disease in both pregnant people and their infants up to six months of age. Despite this, influenza vaccine hesitancy is common, with few countries reporting immunization rates in pregnant people above 50%. In this review, we highlight individual, institutional, and social factors associated with influenza vaccine hesitancy during pregnancy. In addition, we present an overview of the evidence evaluating interventions to address influenza vaccine hesitancy during pregnancy. While some studies have indicated promising results, no single intervention has consistently effectively increased influenza vaccine uptake during pregnancy. Using a social-ecological model of health framework, future strategies addressing multiple levels of vaccine hesitancy will be needed to realize the potential health benefits of prenatal immunization programs.

Pertussis and influenza immunization: perceived attitude and decision of postpartum patients

BACKGROUND

Vaccination of pregnant patients with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) and influenza vaccine during influenza season can reduce maternal and fetal morbidity and mortality; nevertheless, vaccination rates remain suboptimal in this patient population. To investigate the effect of a brief educational counseling session on maternal Tdap and influenza vaccination and determine factors influencing women's decision in regards to receiving Tdap and or influenza vaccine during their pregnancy.

METHODS

A face-to-face semi-structured cross-sectional survey was administered to postpartum patients on their anticipated day of discharge (June 11-August 21, 2018). A brief educational counseling session about maternal pertussis and Tdap vaccine was provided to interested patients after which the Tdap vaccine was offered to eligible patients who did not receive it during their pregnancy or upon hospital admission. Medical records were reviewed to determine if surveyed patients were vaccinated prior to discharge.

RESULTS

Two hundred postpartum patients were surveyed on their day of anticipated discharge. Of those who were surveyed, 103 (51.5%) had received Tdap and 80 (40.0%) had received influenza vaccinations prior to hospitalization. Among immunized patients, the common facilitators were doctor's recommendation (Tdap: 68, 54.4%; influenza: 3, 6.0%), to protect their baby (Tdap: 57, 45.6%; influenza: 17, 34.0%) and for self-protection (Tdap: 17, 13.6%; Influenza: 17, 34.0%). Of the 119 participants who had not received either Tdap or influenza vaccine prior to the survey, the barriers cited were that the vaccine was not offered by the provider (Tdap: 36, 52.2%; influenza: 29, 27.6%), belief that vaccination was unnecessary (Tdap: 5, 7.2%; influenza: 9, 8.5%), safety concerns for baby (Tdap: 4, 5.8%; influenza: 2, 1.9%). Of 97 patients who were not immunized with Tdap prior to admission but were eligible to receive vaccine, 24 (25%) were vaccinated prior to survey as part of routine hospital-based screening and vaccination program, 29 (38.2%) after our survey.

CONCLUSION

Interventions to educate pregnant patients about the benefits of vaccination for their baby, addressing patient safety concerns, and vaccine administration in obstetricians' offices may significantly improve maternal vaccination rates.

Mothers' Impressions and Beliefs About Taking a Booster Dose for COVID-19 Vaccine During Pregnancy and Lactation

OBJECTIVES

This study aimed to explore perceptions and willingness to get coronavirus disease 2019 (COVID-19) booster vaccination among pregnant and lactating women in Jordan.

METHODS

A cross-sectional study using a 29-item web-based questionnaire was conducted. Sociodemographic characteristics, vaccine acceptance, confidence in the booster dose of COVID-19 vaccine, perception of risk for COVID-19, and acceptance to participate in COVID-19 booster vaccine clinical trials were prospectively evaluated. Logistic regression was used to identify factors that might affect the participants' acceptance of a COVID-19 vaccine and their willingness to enroll in clinical trials of a booster dose of COVID-19 vaccine.

RESULTS

Among all participants (pregnant and lactating women, n = 584), 328 (56.2%) intended to receive the booster dose of the COVID-19 vaccine. Predictors of booster dose acceptance were a medical-related degree (OR 1.62, CI 1.06-2.5, p = 0.028), income (OR 0.677, CI 0.52-0.88, p = 0.004), living residency (OR 0.44, CI 0.32-0.60, p < 0.001), knowing pregnant/lactating women previously infected with infectious microbe (OR 1.539, CI 1.07-2.23, p = 0.022), commitment to immunization for children (OR 3.01, CI 1.03-8.82, p = 0.044), receiving an influenza vaccine (OR 1.46, CI 1.04-2.05, p = 0.031), and worried about infectious microbes (OR 1.32, CI 1.15-1.52, p < 0.001). Among participants, only 22.9% were willing to participate in clinical trials of the booster dose of COVID-19 vaccine. The biggest motivator for participation was the participants' desire to help find the best vaccine during pregnancy/lactation (57.5%) while the main barrier towards participation was not wanting to expose themselves and their babies to more side effects (88.0%).

CONCLUSION

This study reported reasonable acceptance of vaccination in a sample of pregnant/lactating women. Vaccination hesitancy for the booster dose was in-line with similar studies on the primary series around the globe, but the willingness to participate in clinical trials was lower than non-pregnant/non-lactating women.

Onge JE, Shafazand S, Potter J. Vaccination in pregnancy: Healthcare provider attitudes and practices

OBJECTIVE

To assess provider attitudes and practices regarding vaccination in pregnancy to discern strategies to increase vaccination rates in pregnancy, given that in the USA, various healthcare organizations recommend that pregnant individuals be vaccinated against influenza, pertussis, and SARS-CoV-2, but vaccination rates among gravidas remain suboptimal across these vaccines.

METHODS

An Institutional Review Board-approved survey was disseminated to obstetric healthcare providers by email from June through October 2021. Questions assessed provider demographics, attitudes, and practices surrounding vaccination in pregnancy. A total of 192 providers consented, 179 initiated the survey, and 153 completed it entirely. Statistical software (SAS) was used to perform descriptive statistics.

RESULTS

All providers strongly agreed/agreed that all pregnant individuals should receive vaccines in pregnancy. Following patient vaccination consent, 13% reported needing to refer patients to alternative sites for vaccine administration. Following patient vaccination decline, 13% did not determine reasons for refusal, 30% did not re-counsel at subsequent visits, and 92% did not ask another staff member to counsel the patient.

CONCLUSION

Despite provider support for maternal immunization, uptake of vaccines in gravidas remains suboptimal, demonstrating a gap between provider recommendations and patient uptake. These data highlight opportunities for intervention regarding counseling and vaccine availability to increase vaccine uptake in pregnancy.

Epidemiology, Clinical Characteristics, and Outcomes of Influenza-Associated Hospitalizations in US Children Over 9 Seasons Following the 2009 H1N1 Pandemic

BACKGROUND

Recent population-based data are limited regarding influenza-associated hospitalizations in US children.

METHODS

We identified children <18 years hospitalized with laboratory-confirmed influenza during 2010-2019 seasons, through the Centers for Disease Control and Prevention's Influenza Hospitalization Surveillance Network. Adjusted hospitalization and in-hospital mortality rates were calculated, and multivariable logistic regression was conducted to evaluate risk factors for pneumonia, intensive care unit (ICU) admission, mechanical ventilation, and death.

RESULTS

Over 9 seasons, adjusted influenza-associated hospitalization incidence rates ranged from 10 to 375 per 100 000 persons each season and were highest among infants <6 months old. Rates decreased with increasing age. The highest in-hospital mortality rates were observed in children <6 months old (0.73 per 100 000 persons). Over time, antiviral treatment significantly increased, from 56% to 85% (P < .001), and influenza vaccination rates increased from 33% to 44% (P = .003). Among the 13 235 hospitalized children, 2676 (20%) were admitted to the ICU, 2262 (17%) had pneumonia, 690 (5%) required mechanical ventilation, and 72 (0.5%) died during hospitalization. Compared with those <6 months of age, hospitalized children ≥13 years old had higher odds of pneumonia (adjusted odds ratio, 2.7 [95% confidence interval, 2.1-3.4], ICU admission (1.6 [1.3-1.9]), mechanical ventilation (1.6 [1.1-2.2]), and death (3.3 [1.2-9.3]).

CONCLUSIONS

Hospitalization and death rates were greatest in younger children at the population level. Among hospitalized children, however, older children had a higher risk of severe outcomes. Continued efforts to prevent and attenuate influenza in children are needed.

Predicted effectiveness of vaccines and extended half-life monoclonal antibodies against RSV hospitalizations in children

Several vaccines and extended half-life monoclonal antibodies (mAbs) against respiratory syncytial virus (RSV) have shown promise in clinical trials. We used age-structured transmission models to predict the possible impact of various RSV prevention strategies including maternal immunization, live-attenuated vaccines, and long-lasting mAbs. Our results suggest that maternal immunization and long-lasting mAbs are likely to be highly effective in preventing RSV hospitalizations in infants under 6 months of age, averting more than half of RSV hospitalizations in neonates. Live-attenuated vaccines could reduce RSV hospitalizations in vaccinated age groups and are also predicted to have a modest effect in unvaccinated age groups because of disruptions to transmission. Compared to year-round vaccination, a seasonal vaccination program at the country level provides at most a minor advantage regarding efficiency. Our findings highlight the substantial public health impact that upcoming RSV prevention strategies may provide.

Perceptions and Attitudes toward COVID-19 Vaccination among Pregnant and Postpartum Individuals

OBJECTIVE

This study aimed to characterize attitudes toward novel coronavirus disease 2019 (COVID-19) vaccination and to evaluate factors associated with vaccine uptake among pregnant individuals.

STUDY DESIGN

An anonymous survey was distributed to a convenience sample of pregnant individuals receiving prenatal care at two large urban academic hospitals in a single health care network in Massachusetts. Individual demographic variables were included in the survey along with questions assessing attitudes toward COVID-19 and vaccination in pregnancy. Data were analyzed using parametric or nonparametric tests when appropriate, and associated odds ratios (OR) were calculated via univariable logistic regression.

RESULTS

There were 684 surveys distributed, and 477 pregnant and postpartum individuals completed the survey, for a response rate of 69.7%. Overall, 233 (49.3%) had received or were scheduled to receive a COVID-19 vaccine. Age, White race, non-Hispanic or Latinx ethnicity, working from home, and typical receipt of the influenza vaccine were associated with COVID-19 vaccination. Further, 276 respondents (58.4%) reported that their provider recommended the COVID-19 vaccine in pregnancy; these participants were more likely to have received a vaccine (OR = 5.82, 95% confidence interval [CI]: 3.68-9.26, p < 0.005). Vaccinated individuals were less likely to be worried about the effects of the vaccine on themselves (OR = 0.18, 95% CI: 0.12-0.27, p < 0.005) or their developing babies (OR = 0.17, 95% CI: 0.11-0.26, p < 0.005). Unvaccinated individuals were less likely to report that it is easy to schedule a COVID-19 vaccine (OR = 0.56, 95% CI: 0.34-0.93, p = 0.02), to travel to receive a vaccine (OR = 0.19, 95% CI: 0.10-0.36, p < 0.005), and to miss work to receive a vaccine (OR = 0.30, 95% CI: 0.18-0.48, p < 0.005).

CONCLUSION

Strategies are needed to improve patient education regarding vaccine side effects and safety in pregnancy. Policy changes should focus on making it feasible for patients to schedule a vaccine and miss work without loss of pay to get vaccinated.

KEY POINTS

· There were racial and ethnic disparities in COVID-19 vaccination.. · Unvaccinated respondents were more likely to be concerned about vaccine effects for themselves or their growing babies.. · Unvaccinated respondents cited work and scheduling-related barriers to vaccination, indicating areas for advocacy..

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.