Tdap Vaccine Research Articles

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

BackgroundAssessment 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. ObjectiveTo 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. MethodsFemale 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. ResultsOf 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. ConclusionsIn 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.

Interventions to Improve Knowledge, Attitudes, and Uptake of Recommended Vaccines during Pregnancy and Postpartum: A Scoping Review.

Tetanus, pertussis, influenza, and COVID-19 vaccines are recommended for the prevention of related morbidity and mortality during pregnancy and postpartum. Despite the established benefits of vaccination for prenatal and postnatal women, maternal vaccination is not universally included in routine antenatal programs, especially in low- and middle-income countries. Furthermore, the uptake of recommended vaccines among pregnant and postpartum women remains below optimum globally. This review aimed to map the evidence on interventions to improve knowledge, attitudes, and uptake of recommended vaccines among pregnant and postpartum women. We conducted a comprehensive and systematic search for relevant literature in PubMed, Scopus, Web of Science, EBSCOhost, and Google Scholar. Overall, 29 studies published between 2010 and 2023 were included in this review. The majority (n = 27) of these studies were from high-income countries. A total of 14 studies focused on the influenza vaccine, 6 on the Tdap vaccine, 8 on both influenza and Tdap vaccines, and only one study on the COVID-19 vaccine. Patient-centered interventions predominated the evidence base (66%), followed by provider-focused (7%), health system-focused (10%), and multilevel interventions (17%). Overall, the effect of these interventions on knowledge, attitudes, and uptake of maternal vaccines was variable.

Acceptance of Routine Vaccines in Pregnancy during the COVID-19 Pandemic.

This study aimed to evaluate the rates of vaccination against infectious diseases (Tetanus, Diphtheria, and Pertussis [Tdap] and influenza) in pregnancy during the coronavirus disease 2019 (COVID-19) pandemic compared to contemporary historical controls. This was a retrospective cohort study comparing rates of Tdap and influenza vaccination in pregnant people who received care at NYU Langone Health and delivered from September 1, 2020, to January 31, 2021 ("COVID cohort") to the same period the prior year ("2019 cohort"). Demographic information, trimester of initiation of prenatal care, insurance status, and medical comorbidities were evaluated. Outcomes were analyzed using chi-square, Fisher's exact test, and multivariable logistic regression, with significance of p < 0.05. In total, 1,713 pregnant people were included. Compared to historical controls, the COVID cohort differed in age, race, timing of initiation of prenatal care, insurance status, and medical comorbidities. After adjusting for these covariates, pregnant people were significantly more likely to accept influenza vaccine in the COVID cohort (adjusted odds ratio [aOR] 1.7, 95% confidence interval [CI] 1.27-2.29) and had similar Tdap acceptance (aOR 1.5, 95% CI 0.99-2.17). However, this trend was not observed for the entire obstetric population; public insurance status and medical comorbidities were associated with lower vaccine rates during the pandemic. For those who had public insurance, rates of influenza vaccination decreased from 83% in 2019 to 40% during COVID (aOR 0.16, 95% CI 0.10-0.24) and for Tdap rates decreased from 93 to 54% (aOR 0.13, 95% CI 0.08-0.21). During the COVID-19 pandemic era, pregnant people at large were more likely to accept the influenza vaccine. However, this trend did not apply to Tdap, and high-risk groups with public insurance and medical comorbidities. This study highlights potential disparities in vaccination rates, which need to be accounted for when evaluating national vaccine trends. These data support increased efforts in vaccine counseling for high-risk populations. · Antenatal flu vaccination increased during the pandemic.. · Antenatal Tdap vaccination was unchanged during the pandemic.. · High-risk pregnant patients had decreased vaccine uptake.. · High-risk subgroups were not included in overarching vaccination trends..

HPV Vaccine Usage Among the U.S. Military Academy Corps ofCadets (2018-2025).

Human papillomavirus (HPV) is a common sexually transmitted virus that infects over 13 million people every year. Over 80% of sexually active adults will acquire HPV at some point in their lives, which is concerning since certain high-risk strains of HPV can cause six types of cancer. Vaccination against HPV is safe and effective, but despite high vaccine efficacy, vaccination rates are low among both service members and civilians. We conducted a retrospective, cross-sectional study to identify the percentage of United States Military Academy (USMA) Cadets who had received at least one HPV vaccine and those who completed the vaccine series. Deidentified vaccination and demographic data were retrieved from the Defense Health Agency Military Health System Data Repository (MDR) for all Cadets who were enrolled at USMA between January 2018 and May 2022 (graduating classes of 2018-2025). To identify the population of Cadets for our study and confirm presence of "any" vaccine in the MDR, Tdap vaccination information was also retrieved. The study population was defined as any Cadet who was enrolled at USMA between January 2018 and May 2022 (graduating classes of 2018-2025) and had record of an HPV and/or Tdap vaccine in the MDR. We compared demographic information between the identified population and known demographics of the USMA population to confirm that the retrieved data were consistent with population demographics. Descriptive statistics were performed to identify demographic differences based on vaccinated and unvaccinated Cadets and to determine the percentage of Cadets who received at least one HPV vaccine. Vaccine series completion was defined as the receipt of three HPV vaccine doses among those who reported receiving at least one dose of HPV vaccine or two doses if vaccinated before the age 15. A total of 9,567 Cadets were assessed for eligibility with 9,433 having Tdap and/or HPV vaccine on record. Of these Cadets, 5,738/9,433 (60.8%) had received at least one HPV vaccine. Of those starting the series, 4,492 completed the two- or three-dose series for a completion rate of 47.6%. We found HPV vaccine completion rate among female Cadets (55.6%) is higher than that of male Cadets (45.2%). More Cadets from minority groups received one vaccine; however, full completion rates were similar for both the groups (48.1%). In contrast, the percentage of Cadets vaccinated against Tdap was 97.2%. Most of those vaccinated received their first vaccine between the ages of 11 and 15 (53.0%) and their final vaccine after they turned 16 (68.9%). Though the vaccination rate among the Corps of Cadets is comparable to the public, it is still less than the 80.0% goal set by the Healthy People 2030 objective. Based on these results, we recommend that the USMA modify its policy on HPV vaccine administration to encourage more vaccine uptake. We also conclude that further studies on the rationale for avoiding the vaccine are necessary to better inform educational campaigns and mitigate stigma.

Quantitative mechanistic model reveals key determinants of placental IgG transfer and informs prenatal immunization strategies.

Transplacental antibody transfer is crucially important in shaping neonatal immunity. Recently, prenatal maternal immunization has been employed to boost pathogen-specific immunoglobulin G (IgG) transfer to the fetus. Multiple factors have been implicated in antibody transfer, but how these key regulators work together to elicit selective transfer is pertinent to engineering vaccines for mothers to optimally immunize their newborns. Here, we present the first quantitative mechanistic model to uncover the determinants of placental antibody transfer and inform personalized immunization approaches. We identified placental FcγRIIb expressed by endothelial cells as a limiting factor in receptor-mediated transfer, which plays a key role in promoting preferential transport of subclasses IgG1, IgG3, and IgG4, but not IgG2. Integrated computational modeling and in vitro experiments reveal that IgG subclass abundance, Fc receptor (FcR) binding affinity, and FcR abundance in syncytiotrophoblasts and endothelial cells contribute to inter-subclass competition and potentially inter- and intra-patient antibody transfer heterogeneity. We developed an in silico prenatal vaccine testbed by combining a computational model of maternal vaccination with this placental transfer model using the tetanus, diphtheria, and acellular pertussis (Tdap) vaccine as a case study. Model simulations unveiled precision prenatal immunization opportunities that account for a patient's anticipated gestational length, placental size, and FcR expression by modulating vaccine timing, dosage, and adjuvant. This computational approach provides new perspectives on the dynamics of maternal-fetal antibody transfer in humans and potential avenues to optimize prenatal vaccinations that promote neonatal immunity.

Association between acceptance of routine pregnancy vaccinations and COVID-19 vaccine uptake in pregnant patients

COVID-19 vaccination is a key approach to reduce morbidity and mortality in pregnant patients and their newborns. Anti-vaccine sentiment has recently increased with unclear impact on pregnant patients. We examined the association between acceptance of tetanus-diphtheria-acellular pertussis (Tdap) and influenza vaccines, considered to be routine pregnancy vaccines, and COVID-19 vaccine acceptance. Secondarily, we identified other predictors of COVID-19 vaccine uptake and described pregnancy outcomes in patients who were and were not vaccinated during pregnancy. A retrospective cohort study of all patients who delivered at a single site from December 2020 - March 2022. Demographic, pregnancy, neonatal, and vaccination data were abstracted from the electronic medical record, which imports vaccine history from the California Immunization Registry. The relationship between influenza and Tdap vaccine acceptance, other baseline characteristics, and COVID-19 vaccine uptake was assessed using univariable and multivariable regression analysis. Of the 7857 patients who delivered during the study period, 4410 (56.1%) accepted the COVID-19 vaccine. Of those who received the COVID-19 vaccine, 3363 (97.6%) and 3049 (88.5%) received influenza and Tdap vaccines, respectively. Patients were more likely to receive the COVID-19 vaccine if they had advanced maternal age, obesity, Asian race, and private insurance. After adjustment for baseline differences, COVID vaccine acceptance was associated with receipt of Tdap (aOR 2.10, 95% CI 1.90-2.33) and influenza vaccines (aOR 2.83, 95% CI 2.55-3.14). There were no differences in preterm birth, low birthweight, and NICU admission between patients who received and did not receive the COVID-19 vaccine. Patients were more likely to accept COVID-19 vaccination if they received Tdap or influenza vaccinations. Older age, obesity, Asian race, and private insurance were independent predictors of vaccine uptake. Disparities in COVID-19 vaccination uptake bear further exploration to guide efforts in equitable and widespread vaccine distribution.

Safety and immunogenicity of SIIPL Tdap, a new tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine, in healthy subjects 4–65 years of age: A Phase II/III randomized, observer-blinded, active controlled, multicenter clinical study in Germany

BackgroundThis study assessed the safety and immunogenicity of a new booster vaccine against tetanus, diphtheria, and pertussis manufactured by Serum Institute of India Pvt. Ltd (SIIPL Tdap). MethodsThe Phase II/III trial was randomized (2:1), observer blinded and active controlled. Healthy subjects aged 4–65 years received a single dose of either SIIPL Tdap or comparator Tdap vaccine (Boostrix®, GlaxoSmithKline, Belgium), and were followed-up for 30 days. Blood samples for safety and immunogenicity assessments were collected pre-vaccination and on day 30 post-vaccination. The study assessed safety and reactogenicity of SIIPL Tdap compared to the comparator Tdap as well as the co-primary immunogenicity outcomes: (i) seroprotection rates against diphtheria toxoid (DT) and tetanus toxoid (TT) and (ii) the booster response rates against pertussis toxoid (PT), filamentous hemagglutinin (FHA) and pertactin (PRN) 30 days post-vaccination in all study subjects. A margin of −10 % was used for non-inferiority testing. Secondary outcomes included the booster response rates against DT and TT, seropositivity rates against pertussis antigens, and antibody geometric mean concentrations (GMCs) for all vaccine components. ResultsAt Day 30 post-vaccination, SIIPL Tdap was assessed as non-inferior to the comparator Tdap in terms of: i) seroprotection rates against DT (94.4 % vs. 94.9 %) and TT (99.9 % vs. 100 %) and ii) pertussis booster response rates (93.8 % vs. 88.4 % anti-PT, 89.7 % vs. 90.9 % anti-FHA and 86.3 % vs. 84.4 % anti-PRN), for SIIPL Tdap versus comparator Tdap, respectively. GMCs for anti-PT and anti-PRN were higher in subjects vaccinated with SIIPL Tdap compared to comparator Tdap. All other secondary outcomes were comparable. The overall frequency of local and systemic solicited AEs was comparable; no treatment related SAEs were reported. ConclusionsBooster vaccination with SIIPL Tdap was non-inferior to comparator Tdap with respect to the immunogenicity of the vaccine components and was equally well tolerated.EudraCT number: 2019-002706-46.

A Multivariate Probit Regression of the Uptake of Adolescent Vaccines Among Racial/Ethnic Minority Adolescents Before and During the COVID-19 Pandemic

PurposeThe uptake of adolescent vaccines has improved over the years. However, research of the effects of the COVID-19 pandemic on this uptake among racial/ethnic minority adolescents has been limited. This study was conducted to compare the probability of uptake of the human papillomavirus (HPV); tetanus, diphtheria, and acellular pertussis (Tdap); and quadrivalent meningococcal conjugate (MenACWY) vaccines among racial/ethnic minority adolescents ages 13–17 years in 2019, 2020, and 2021. MethodsUsing a cross-sectional design to examine data from the National Immunization Survey–Teen (2019–2021), multivariate probit regression was used to model variation in uptake of these three adolescent vaccines (n = 38,128). The outcome measures were HPV, Tdap, and MenACWY vaccine uptake. ResultsThe probability of uptake of HPV vaccine was higher in 2020 (Coef = 0.09 [95% confidence interval (CI), 0.03–0.16]) and 2021 (Coef = 0.07 [95% CI, 0.00–0.15]) than in 2019. The probability of uptake of MenACWY vaccine was higher in 2020 (Coef = 0.08 [95% CI, 0.02–0.15]) than in 2019. The probability of uptake of recommended vaccines varied among racial/ethnic minorities with non-Hispanic Black adolescents exhibiting higher probability of uptake of HPV vaccine (Coef = 0.10 [95% CI, 0.01–0.19]) than Tdap vaccine. U.S. Census region and insurance status were associated with the uptake of all recommended vaccines. DiscussionProgress in the uptake of these recommended vaccines may not have been interrupted by the COVID-19 pandemic. Also, disparities in uptake of the recommended vaccines still exist despite increased uptake during the pandemic. Future research should examine the disparities as well as examine regional differences in the uptake of these three adolescent vaccines.

Group prenatal care for pregnant women with opioid use disorder: Preliminary evidence for acceptability and benefits compared with individual prenatal care.

The effectiveness of group prenatal care (G-PNC) compared with individual prenatal care (I-PNC) for women with opioid use disorder (OUD) is unknown. The objectives of this study were to (1) assess the acceptability of co-locating G-PNC at an opioid treatment program and (2) describe the maternal and infant characteristics and outcomes of pregnant women in treatment for OUD who participated in G-PNC and those who did not. This was a retrospective cohort study of 71 women (G-PNC n = 15; I-PNC n = 56) who were receiving treatment for OUD from one center and who delivered in 2019. Acceptability was determined by assessing the representativeness of the G-PNC cohorts, examining attendance at sessions, and using responses to a survey completed by G-PNC participants. The receipt of health services and healthcare use, behaviors, and infant health between those who participated in G-PNC and those who received I-PNC were described. G-PNC was successfully implemented among women with varying backgrounds (e.g., racial, ethnic, marital status) who self-selected into the group. All G-PNC participants reported that they were satisfied to very satisfied with the program. Increased rates of breastfeeding initiation, breastfeeding at hospital discharge, receipt of the Tdap vaccine, and postpartum visit attendance at 1-2 weeks and 4-8 weeks were observed in the G-PNC group compared with the I-PNC group. Fewer G-PNC reported postpartum depression symptomatology. Findings suggest that co-located G-PNC at an opioid treatment program is an acceptable model for pregnant women in treatment for OUD and may result in improved outcomes.

Immunogenicity of tetanus, diphtheria and acellular pertussis vaccination among pregnant women living with and without HIV.

Vaccination during pregnancy with tetanus-diphtheria-acellular pertussis (Tdap) vaccine is recommended to protect the young infants against pertussis. There is a paucity of data on immune responses to Tdap in pregnant women living with HIV (PWLWH), and its impact on the protection of their infants has not been described. In an open label phase IV clinical trial in South Africa, we evaluated the immunogenicity and safety of Tdap in PWLWH compared with HIV-uninfected women. Antigen-specific immunoglobulin G (IgG) to pertussis toxoid, filamentous hemagglutinin, pertactin, fimbriae, diphtheria and tetanus were measured by electrochemiluminescence-based multiplex assay. Overall 91 PWLWH and 136 HIV-uninfected pregnant women were enrolled. All PWLWH were on antiretroviral treatment and 94.5% had HIV viral loads <40 copies per millilitre. Antibody levels pre-vaccination were lower among PWLWH compared with HIV-uninfected women for all antigens. At one-month post-vaccination PWLWH compared with HIV-uninfected women had lower fold-increase and antibody concentrations for all epitopes. Also, a lower proportion of PWLWH achieved ≥4-fold increase from pre to post-vaccination for pertussis toxoid and pertactin, or diphtheria IgG levels ≥0.1IU/mL and ≥1IU/mL post-vaccination. Adverse events post-vaccination were similar in PWLWH and HIV-uninfected. Tdap vaccination was safe and immunogenic. PWLHW had, however, attenuated humoral immune responses, which could affect the effectiveness of protecting their infants against pertussis compared with those born to women without HIV. ClinicalTrials.gov identifier: NCT05264662.

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

ABSTRACT Many illnesses can become especially serious when contracted within the first year of life; pertussis remains quite deadly despite recent medical advances in disease prevention. Current guidance on vaccination in the United States includes 3 doses of the DTaP (diphtheria, tetanus toxoid, and acellular pertussis) vaccine beginning at 2 months of age, but this regimen leaves infants younger than that very vulnerable to illness. Research has shown both that vaccinating mothers with tetanus toxoid reduces tetanus, diphtheria, and pertussis (Tdap) between 27 and 36 weeks of gestation significantly reduces instances of pertussis in infants younger than 2 months, and that maternal vaccination rates have risen in the last few years. However, research is lacking in analyzing the relationship between vaccination rates in pregnant mothers and the burden of pertussis in infants in the United States. This study was designed to assess data from 2000 to 2019 and examine the association of Tdap vaccination during pregnancy with trends in infant pertussis. This analysis included data obtained from the National Notifiable Diseases Surveillance System between 2000 and 2019. This included a total of 57,460 cases of pertussis in infants younger than 1 year and a total of 19,322 cases in infants younger than 2 months. The rate of pertussis incidence for infants younger than 2 months in the time period before the implementation of prenatal Tdap was calculated to be 165.3 per 100,000 individuals, with no significant trend observed annually (P = 0.28). After the implementation of routine maternal Tdap, incidence decreased to 80.9 per 100,000 infants between 2017 and 2019. Accounting for both time periods, the mean annual incidence was calculated as 121.8 per 100,000 infants younger than 2 months. Annual incidence also showed a significant decreasing trend in the period after implementation of maternal Tdap vaccination (slope: −14.53 per 100,000 infants per year; P = 0.001). The change in trends before and after this implementation was also significant (P = 0.01). In a slightly older age group of 6 to 12 months of age, mean annual incidence of pertussis was 19.7 per 100,000 infants. In the time period before implementation of maternal Tdap, incidence among infants aged 6 to 12 months was consistently 4 to 12 times less than infants younger than 2 months and did not significantly change after the implementation of the maternal vaccine. Comparing the 2 age groups, there was no significant change in the difference in incidence between infants younger than 2 months and those between 6 and 12 months in the period before the maternal vaccine, and after its implementation, there was a significant decrease in the incidence difference between the 2 groups (P &lt; 0.001). These results suggest an association between the maternal Tdap vaccination and trends of pertussis incidence in infants younger than 2 months. This also indicates a possible reduction in disease burden attributable to maternal Tdap vaccination before delivery. Limitations of this study include limited availability of individual maternal vaccination status, as well as an inability to identify if any infants were vaccinated before the age of 2 months. Further research should focus on clinical impact of the Tdap vaccination in context with the later DTaP vaccination and on analyzing the trends in disease associated with both vaccinations. Clinical guidelines should also be examined to ensure that public health trends and individual health trends are in alignment.

Tdap vaccine in pregnancy and immunogenicity of pertussis and pneumococcal vaccines in children: What is the impact of different immunization schedules?

BackgroundIn 2019, the 3 + 1 schedule for children’s vaccination (2–4–6–18 months old) was changed for a reduced 2 + 1 schedule (2–4–12 months old) in Quebec, Canada. We compared the post-booster anti-pertussis and anti-pneumococcus IgG antibody concentrations among children of Tdap-vaccinated and unvaccinated mothers for different vaccine schedules and vaccine formulations. MethodsWe conducted an observational cohort study. An invitation letter to potential participants was provided during a routine vaccination visit. Children’s blood samples were analyzed post-booster at 13 (2 + 1 schedule) or 19 (3 + 1 schedule) months of age for antibodies against pertussis antigens (pertussis toxin (PT), filamentous hemagglutinin (FHA) and pertactin (PRN)) and pneumococcal antigens (serotypes 4, 18C, 19A, and 19F). IgG concentrations among children of Tdap-vaccinated and unvaccinated mothers for each vaccination schedule were compared using geometric mean concentrations (GMCs) and GMC ratios (GMRs), adjusting for potentially immune-response-influencing factors (aGMR). Serotype-specific pneumococcal seroprotection rates were also compared. ResultsA total of 360 children were included for pertussis analysis and 248 for pneumococcal analysis. For the 2 + 1 schedule, 13-month-old children of Tdap-vaccinated mothers had lower GMCs against PT, FHA, and PRN, with aGMR (95 %CI) of 0.77 (0.65–0.90), 0.66 (0.55–0.79), 0.72 (0.52–0.99), respectively. For the 3 + 1 schedule, at 19 months old, the interference appeared to be attenuated (higher aGMR values). GMCs against PT were slightly higher in the 3 + 1 than the 2 + 1 schedule: 126.5 IU/ml vs 91.6 IU/ml; aGMR = 1.27. GMCs against PT, FHA and PRN were slightly higher among children who received Infanrix hexa® compared to those who received Pediacel® at 12 months old. For pneumococcal antibodies, at 13 months old, there was no strong evidence of immune interference in children of Tdap-vaccinated mothers. ConclusionInfant vaccination schedule may influence immune interference associated with maternal Tdap vaccination. More studies are needed to assess the clinical impact of this interference on children’s protection.

Are maternal vaccines effective and safe for mothers and infants? A systematic review and meta-analysis of randomised controlled trials

IntroductionMaternal vaccination is a promising strategy to reduce the burden of vaccine-preventable diseases for mothers and infants. We aimed to provide an up-to-date overview of the efficacy and safety of...

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.

COVID-19 Vaccination Recommendations and Practices for Women of Reproductive Age by Health Care Providers - Fall DocStyles Survey, United States, 2022.

Pregnant and postpartum women are at increased risk for severe illness from COVID-19 compared with nonpregnant women of reproductive age. COVID-19 vaccination is recommended for all persons ≥6 months of age. Health care providers (HCPs) have a unique opportunity to counsel women of reproductive age, including pregnant and postpartum patients, about the importance of receiving COVID-19, influenza, and tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccines. Data from the Fall 2022 DocStyles survey were analyzed to examine the prevalence of COVID-19 vaccination attitudes and practices among HCPs caring for women of reproductive age, and to determine whether providers recommended and offered or administered COVID-19 vaccines to women of reproductive age, including their pregnant patients. Overall, 82.9% of providers reported recommending COVID-19 vaccination to women of reproductive age, and 54.7% offered or administered the vaccine in their practice. Among HCPs who cared for pregnant patients, obstetrician-gynecologists were more likely to recommend COVID-19 vaccination to pregnant patients (94.2%) than were family practitioners or internists (82.1%) (adjusted prevalence ratio [aPR]=1.1). HCPs were more likely to offer or administer COVID-19 vaccination on-site to pregnant patients if they also offered or administered influenza (aPR=5.5) and Tdap vaccines (aPR=2.3). Encouraging HCPs to recommend, offer, and administer the COVID-19 vaccines along with influenza or Tdap vaccines might help reinforce vaccine confidence and increase coverage among women of reproductive age, including pregnant women.

The Effectiveness of a Mobile Health Clinic Delivering Mandatory and Elective Middle School Immunizations: A Descriptive Analysis.

Mobile health clinics serve a unique role in which they can offer affordable and adaptable care to the population they serve. The Edward Via College of Osteopathic Medicine (VCOM) mobile clinics began in 2020 as a partnership with the South Carolina Department of Health and Environmental Control (SCDHEC) to address the low vaccination rates that resulted from the COVID-19 pandemic. This study is a descriptive analysis that examines the number of vaccinations of tetanus, diphtheria, and pertussis (Tdap) and human papillomavirus (HPV) at different locations of administration including pediatrician offices, the novel VCOM mobile vaccination clinic, and the Spartanburg Health Department. The variables of interest and the study endpoints focused on Tdap and HPV vaccinations among students aged 11-12 years old in Spartanburg County according to the type of healthcare delivery location. From April to May of 2021, the VCOM mobile clinic was able to administer 279 Tdap vaccines and 189 HPV vaccines to students at local middle schools, which surpasses the number of vaccines administered at other sites from August 2020 to May 2021 when compared individually for both Tdap and HPV vaccinations. By assessing the total volume of vaccines administered by each group, the VCOM mobile clinic was established as an effective method of delivery and played a crucial role in the vaccination efforts of the Spartanburg community. Mobile medical units should be considered for similar efforts in providing care to resource-limited communities and those with limited access to care.

Adherence to Recommended Immunization Schedules in Patients with Inflammatory Bowel Disease on Biologics and Small Molecule Therapies

Introduction: Patients with inflammatory bowel disease (IBD) on biologic therapies are at increased risk of infections, emphasizing the importance of immunization. This study aimed to assess vaccination prevalence among patients with IBD on specific biologic therapies. Methods: A survey-based cross-sectional study was conducted at an IBD center, including patients receiving different biologic therapies from 1 January 2022 to the 30 April 2023. Demographic and vaccination data were collected using patient electronic records and patient interviews. Results: A total 394 patients (100%) received the measles, mumps, rubella (MMR), tetanus, reduced diphtheria, and acellular pertussis (Tdap) vaccine. A total of 79 patients (20%) received the influenza vaccine, 40 patients (10.2%) were vaccinated against hepatitis A (HAV), and 34 patients (8.6%) received the pneumococcal vaccine. From the 103 female patients who are eligible to take human papillomavirus (HPV) vaccine, only 7 (6.8%) received it. Out of the 100 eligible patients above the age of 50, only 9 (9%) received the herpes zoster (HZ) vaccine. Conclusion: The uptake of certain vaccines such as Hepatitis B (HBV), seasonal influenza, HAV, pneumococcal, HZ and HPV vaccines among patients with IBD were below expectations. These findings highlight the need for interventions to improve patients’ awareness and adherence to prevent infectious complications in patients with IBD.

Effectiveness of maternal immunisation with a three-component acellular pertussis vaccine at preventing pertussis in infants in the United States: Post-hoc analysis of a case-control study using Bayesian dynamic borrowing

BackgroundImmunisation during pregnancy with a tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine can protect infants against pertussis between birth and paediatric vaccination. We aimed to estimate the vaccine effectiveness (VE) of third-trimester pregnancy immunisation with the three-component acellular pertussis (Td3ap) vaccine at preventing pertussis in infants <2 months in the United States (US), to support a label update. MethodsWe performed a post-hoc sub-analysis of a case-control study conducted in six US Emerging Infections Program Network states between 2011 and 2014. Our analysis included only cases and controls whose mothers were either vaccinated with Td3ap or did not receive any Tdap vaccine. The association between Td3ap maternal immunisation and pertussis in infants was assessed for US data using a frequentist method with conditional logistic regression. A robustified analysis was conducted using Bayesian dynamic borrowing of non-US data, considering a mixing-weighted prior of 90% for historical non-US VE data, and of 10% for a vague prior. VE was estimated as (1-odds ratio) × 100%. Sensitivity analyses accounting for the impact of each non-US study, different mixing weights and missing/ambiguous data were performed. ResultsWe included 108 cases and 183 controls. Based on US data, the estimated VE of third-trimester maternal immunisation with Td3ap at preventing pertussis in infants <2 months was 78.0% (95% confidence interval: −38.0; 96.5). VE estimated by Bayesian dynamic borrowing of non-US data (with a 90% weight for historical data) was 83.4% (95% credible interval: 55.7; 92.5); sensitivity analyses produced similar VE estimates. ConclusionsEffectiveness of third-trimester pregnancy immunisation with Td3ap at preventing infant pertussis in the US is very likely to be ≥ 50% and is most likely ∼ 80%. Bayesian dynamic borrowing of non-US VE data allowed overcoming the limited power (due to small sample size) of a brand-specific sub-analysis by considering additional evidence.

Pertussis antibodies and vaccination coverage among healthcare professionals in Brazil is inadequate: A cross-sectional serological study

IntroductionWorldwide, tetanus-diphtheria-acellular pertussis (Tdap) vaccination coverage of healthcare professionals (HCPs) is below 40%, but this data is not available for Brazil. We hypothesize that a high number of HCPs are not immune to pertussis in Brazil. Main objective was to determine the seroprevalence of anti-pertussis toxin (anti-PT IgG) among HCPs. Secondary objectives were to evaluate Tdap vaccination coverage, to assess predictive factors associated with anti-PT IgG, and to estimate the decay of anti-PT IgG and time to Tdap vaccination. MethodsObservational cross-sectional serological study in 352 HCPs who worked at São Paulo Hospital - Federal University of São Paulo (UNIFESP) in 2020, approved by UNIFESP Ethics Committee. Data collected included sociodemographics, knowledge about Tdap, and vaccination status. Anti-PT IgG were quantified by ELISA: <10 IU/mL seronegative and ≥ 10–1000 IU/mL seropositive. Titers ≥ 10–50 IU/mL were classified low positivity, indicating no recent B. pertussis infection or Tdap vaccination; >50 IU/mL high positivity, indicating recent B. pertussis infection or Tdap vaccination, and > 100 IU/mL as acute B. pertussis infection or Tdap vaccination in the previous year. Comparisons were done by Chi-square test, multivariable logistic regression, and Pearsońs correlation, at 5% p-level. Results331/352 HCPs were not aware the Brazilian National Immunization Program recommends Tdap for all HCPs and pregnant women. 68/339 HCPs received Tdap (mean 3.1 ± 2.0 years). 55/352 were seronegative for pertussis, all unvaccinated. 56/271 with no history of Tdap vaccination had high positivity. The probability of anti-PT IgG > 50 IU/mL was 11.5 times higher in Tdap vaccinated HCPs than in non-vaccinated (p < 0.001). There was a weak but significant correlation between anti-PT IgG and interval of Tdap vaccination (r = 0.404; p = 0.001). Anti-PT IgG dropped 5 IU/mL/year (p = 0.001). ConclusionBetter education of HCPs on needs and benefits of Tdap vaccination is critical. Goals must be to improve HCPs vaccination coverage.

A comparison of electronic health records and the Oregon state immunization registry for human papilloma virus vaccine delivery (2005–2022)

IntroductionImmunization Information Systems (IIS) play an important information-sharing role at the point of care, and provide vital vaccination data for research studies and policy-makers. Previous validation studies comparing the accuracy of state registry data to health records have had mixed results. MethodsWe conducted a retrospective review of EHR vaccination data for 9–17 year-old patients from 10 Oregon primary care clinics who had at least one ambulatory care visit in the past 3 years from the date of validation data collection. Data on 100 age eligible youth were captured per clinic. We compared HPV and Tdap vaccinations captured in the EHR to the Oregon ALERT IIS. All clinics were located in rural areas with both family medicine (n = 7) and pediatric (n = 3) primary care clinics. ResultsOverall agreement for HPV vaccination between EHR and ALERT IIS was 89.4 % (k = 0.83; p < 0.05). For Tdap vaccination overall agreement was 80.8 % (k = 0.60; p < 0.05). Pediatric clinics showed a higher overall vaccine agreement for both HPV at 93.3 % (k = 0.89; p < 0.05) and Tdap at 95.3 % (k = 0.90; p < 0.05). Among clinics that used bidirectional data exchange (only family medicine clinics), HPV agreement was higher at 91 % (k = 0.85) versus 88 % (k = 0.81; p < 0.05) and was lower for Tdap 75 % with bidirectional data exchange (k = 0.50) versus 86 % without bidirectional data exchange (k = 0.70; p < 0.05). When the EHR and ALERT IIS disagreed, ALERT ISS usually had additional vaccines. ConclusionsALERT IIS data provides more accurate data than EHRs can provide when measuring vaccine delivery among adolescents in rural Oregon.