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Background: Kinetics of Tdap-induced maternally-derived antibodies in infants are poorly understood. Pre-Tdap era data suggest that maternal pertussis antibodies in infants have a half-life of approximately 5-6 weeks., Methods: 34 mother-infant pairs had blood collected before maternal Tdap vaccination, 4 weeks later, at delivery (maternal and cord), and at infant ages 3 and 6 weeks from June 2014-March 2015. Immunoglobulin G (IgG) to pertussis toxin (PT), filamentous hemagglutinin (FHA), fimbrial proteins (FIM) and pertactin (PRN) was quantified by multiplex luminex assay (IU/ml). Geometric mean concentrations (GMCs) with 95% confidence intervals (C.I.) and half-life of pertussis antibodies were calculated., Results: Tdap was administered to 34 women (mean age 31.1 years) at mean gestation 30.7 weeks (28-32.7). Mean neonatal gestation was 39.1 weeks (36-41.1) and mean birthweight was 3379 g (2580-4584). Four weeks post-Tdap vaccination, maternal pertussis-specific IgG GMCs increased ≥4-fold in 59%, 41%, 29% and 44% of women for PT, FHA, FIM and PRN, respectively, and then waned. The transplacental transport ratio of pertussis antibodies was 1.35 for PT, 1.41 for FHA, 1.31 for FIM and 1.36 for PRN. Between birth and age 6 weeks, infant serum GMC for PT-specific IgG decreased from 55.1 IU/mL (38.6-78.6) to 21.1 IU/ml (14.7-30.2), and the proportion of infants with PT levels ≥10 IU/ml fell from 97% to 67%. Half-life of pertussis-specific IgG in infants in days was 29.4 (95% CI 27.3-31.7) for PT, 29.8 (95% CI 27.7-32.2) for FHA, 31.2 (95% CI 28.9-33.7) for PRN, and 35.8 (95% CI 30.1-44.3) for FIM., Conclusion: The half-life of pertussis-specific antibodies in infants induced by maternal Tdap vaccination (29-36 days) is shorter than previously reported. Understanding how the durability of passively-acquired antibodies impacts infant susceptibility to pertussis and response to primary vaccination is critical to refine prevention strategies., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: CMH has received research grants from Sanofi Pasteur and Novartis Vaccines and served on an Advisory Board for Novartis Vaccines, Pfizer Inc., and Novavax Inc. CJB is a consultant for Pfizer, Inc. All authors have approved the final article., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objectives: Tetanus, diphtheria and acellular pertussis (Tdap) and influenza vaccination is recommended during each pregnancy but uptake is suboptimal. We evaluated knowledge and acceptance of vaccination recommendations among pregnant women., Methods: Prospective, convenience survey of pregnant women presenting for antenatal care at the Pavilion for Women, Texas Children's Hospital, Houston, and their healthcare providers., Results: 796 of 825 (96.5%) of women and 63 of 87 (72.4%) providers completed surveys. Mean age of pregnant women was 30.2 (18-45) years. Self-identified race/ethnicity was 45% white, 26% Hispanic, 13% black, 12% Asian and 4% other. Most women had college degrees (84%) and private health insurance (83%). Mean gestation was 28.5 weeks with 4.8%, 37.8% and 57.4%, in the 1st, 2nd and 3rd trimesters, respectively. Women used various sources for pregnancy information (personal contacts, providers, print, audiovisual and online media) but 89.1% cited a provider as their most trusted source, predominantly (85.8%) their physician. 668 (84%) knew vaccines are recommended during pregnancy, specifically influenza (77%) and Tdap (61%) vaccines. 659 (83%) were willing to receive vaccines if recommended by their physician. Factors impacting vaccination decisions included safety for baby, safety for mother and sufficient information, scoring 4.7, 4.5 and 4.2, respectively, on a 5-point scale; less important were additional visit time (2.6), cost (1.9) or needle phobia (1). Women surveyed in the 3rd trimester showed greater acceptance than those earlier in gestation (87% vs 78%; P0.003). Maternal education, ethnicity, insurance, multiple gestation or history of serious illness in a prior infant did not affect willingness to receive vaccines., Conclusions: Pregnant women are willing to accept vaccination in pregnancy if recommended by their physician and if sufficient discussion of safety and rationale occurs. Strong physician recommendation, as reported for pediatric vaccination, is essential to optimizing uptake of vaccines during pregnancy., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objectives: Tetanus, diphtheria and acellular pertussis (Tdap) vaccine is recommended during each pregnancy, but national uptake is poor. We assessed Tdap uptake in a tertiary referral hospital served by university-affiliated and private obstetrical offices., Methods: Review of women delivering at Texas Children's Hospital Pavilion for Women, Houston, Texas, during April 2013-June 2014., Results: 6577 deliveries occurred during the study period. Mean maternal age was 29.8 years (range 13-49); race/ethnicity was 43.6% White, 27% Hispanic, 21% Black, 7.1% Asian, and 1.3% other. 252 were multiple gestations; 229 sets of twins, 21 triplets and 2 quadruplets. 3678 (56%) women received Tdap during pregnancy, 249 (3.8%) postpartum and 100 (1.5%) received Tdap pre-conception only. Tdap uptake during pregnancy increased from 36% in April 2013 to a sustained uptake of greater than 61% since November 2013, with increases noted coincidental with presentations highlighting Tdap maternal immunization recommendations at faculty and staff meetings, and the release of the ACOG "toolkit". When antenatal Tdap vaccine was administered, mean gestation at receipt of Tdap was 31.4 weeks and 95% of vaccinated women received Tdap at the recommended gestation interval of 27-36 weeks, 71.6% during the 28-32 week window believed optimal for placental transport and 98.5% at least 7 days before delivery. Of 19 women with two pregnancies during the study period, four (21%) had Tdap during both. Black women were less likely to receive antenatal Tdap than women of other race/ethnicity (41% versus 60%; P<0.001)., Conclusions: Sustained antenatal Tdap uptake rates exceeding 61% were achieved after strategies to increase awareness of recommendations were introduced and 95% of women were immunized at a gestation optimal for efficient maternal antibody placental transport. Further increases in uptake will require system changes such as best practice alerts in electronic medical records., (Copyright © 2015. Published by Elsevier Ltd.)

Objective: Adult vaccination coverage is low and current strategies are unlikely to achieve Healthy People 2020 targets. We determined the attitude of adult infant contacts toward recommended adult vaccines and their willingness to receive vaccines should they be available during hospital visits or prenatal or infant clinic appointments., Methods: Survey of predominantly Hispanic, underinsured and medically underserved infant contacts at a county hospital in Houston, Texas where a pertussis cocooning program is offered., Results: Two hundred and eighty-five contacts (mean age 32.8 years [18-73]; 94.8% Hispanic) participated. Most were fathers (58.2%), followed by aunts (19%), and grandparents (12.3%). Participants used many health information sources. 221 (77.5%) considered healthcare providers the most influential on their decisions but only 51.6% reported healthcare visits within the prior year. Forty-one (14.4%) discussed family vaccinations during prenatal visits. Preferred locations for adult vaccination were hospital or clinic-based (96.5%). Lack of knowledge (22.8%), fear of pain/needles (14.7%), work commitments (14%), lack of transport (11.2%), cost (10.2%) and fear of side effects (5.3%) were barriers to vaccination. More males than females reported fear of pain/needles and work commitments (P 0.01 and P 0.02, respectively), and more females lack of transport (P<0.001) as barriers. Most planned to (76.1%) or had received (7%) pertussis vaccine; if available, 73.3%, 53.3% and 50.5% expressed willingness to receive vaccines against influenza, pneumonia and meningitis, respectively. Age, ethnicity or education was not associated with willingness to be vaccinated. Vaccine acceptance was higher in females than males for pertussis (P 0.04), influenza (P 0.008), pneumonia (P 0.04), and meningitis (P 0.006) vaccines by multiple regression analysis., Conclusions: Most adults were willing to be vaccinated if offered during hospital visits or clinic appointments for mother or infant. Development and expansion of recommended immunization platforms, such as the cocooning platform, offers the opportunity to increase adult vaccination coverage., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objectives: Data are limited on whether providers understand parental attitudes to recommended childhood immunizations. We determined parental attitudes and assessed how accurately providers estimated parental opinions., Methods: Survey of parents and providers (pediatricians, nurses, medical assistants) in randomly selected practices in Houston, Texas. Surveys assessed demographics, perceptions of immunization importance, safety and efficacy, and acceptability of vaccine delivery. Providers estimated parental responses., Results: 401 parents (82% mothers, 12% fathers, 6% other) and 105 providers participated. Parents thought vaccines were important for health (median score 9.5; 0=not important, 10=extremely important) but also were concerned regarding vaccine safety and side effects (8.9 on 0-10 scale). 309 (77%) agreed that vaccines effectively prevent disease. Route of administration mattered to 147 (37%), who preferred injection (9.0) over oral (7.3) or intranasal (4.8) routes. Although parents would prefer three or fewer injections per visit, preventing more diseases (189 [47.6%]) was more important than number of injections (167 [42.3%]) when deciding the number of vaccines allowed per visit. White parents rated vaccines less important in preventing some illnesses than did non-white (P≤0.006 for meningitis, hepatitis, HPV, influenza and rotavirus) and rated number of injections per visit more important than number of diseases prevented (51.6% white versus 34.2% non-white; P 0.002). Providers underestimated parental attitudes toward vaccine importance (particularly influenza and HPV), and overestimated the proportion of parents who thought route of administration mattered (63%) and that number of injections per visit was the most important factor (76%) around parental vaccine decisions (P<0.001 for parent-provider mismatch)., Conclusions: Most surveyed parents believe vaccines are important for child health and rate disease prevention higher than number of injections entailed. Providers underestimate the importance of some vaccines to parents and overestimate parental concerns regarding route of administration. Future research should focus on how this mismatch impacts parental vaccine decisions., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

We provided CDC recommended postpartum tetanus, diphtheria, acellular pertussis (Tdap) immunization to medically underserved, uninsured women in Houston through a standing order protocol. From January 7-April 30, 2008, 1129 of 1570 (72%) postpartum women (93% Hispanic; 11% < or = 19 years) received Tdap before hospital discharge. Tdap uptake was 96.2% in women without self-reported contraindications. Recall of immunization history was inaccurate in 32% of unimmunized women who reported receiving antepartum immunization. Black women refused Tdap more often than other ethnicities (24% versus 8%; P=0.003). Postpartum Tdap immunization was successfully implemented in a high-risk population through a standing order protocol. Barriers to postpartum immunization include inaccurate immunization history and the need for ongoing targeted education.