Antibodies In Cord Blood Research Articles

Antibody status at delivery and pregnancy outcomes during the first Danish COVID-19 wave.

We aimed to investigate the prevalence of SARS-CoV-2 infection and SARS-CoV-2 antibodies in parturient women and their newborns during the first Danish COVID-19 wave and to identify associations with maternal background characteristics, self-reported symptoms, and pregnancy outcomes. In a single-centre, prospective cohort study from Denmark, we invited 1,883 women with singleton pregnancies giving live birth from 25 May 2020 to 2 November 2020. Hereof, 953 (50.6%) women were included. Nasopharyngeal swabs, maternal and umbilical cord blood samples, and questionnaires were collected. Medical records were available for participants and non-participants. SARS-CoV-2 antibodies were found in 1.3% of the women. All newborns of seropositive women had SARS-CoV-2 antibodies in cord blood. No association was found between SARS-CoV-2 antibodies and pregnancy outcomes. Self-reported loss of smell correlated with seropositivity (p less-than 0.001). No women were hospitalised due to COVID-19 during pregnancy or had a positive nasopharyngeal swab intrapartum. The prevalence of COVID-19 in pregnancy was low during the first wave. Maternal SARS-CoV-2 antibodies were associated with antibodies in cord blood, loss of smell and positive SARS-CoV-2 swab during pregnancy, but not with any adverse pregnancy outcomes. Ferring Pharmaceuticals funded part of the study. The study was approved by the Regional Committee on Health Research Ethics (H-20028002) and the Danish Data Protection Agency (P-2020-264).

COVID-19 Vaccination and Infection: Effect on Maternal and Cord Blood Antibody Levels at Delivery

COVID-19 Vaccination and Infection: Effect on Maternal and Cord Blood Antibody Levels at Delivery

SARS CoV-2 Antibodies in Cord Blood of Neonates Delivered to Pregnant Mothers Vaccinated for COVID-19

Background: The recent novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) pandemic has been responsible for millions of deaths globally. Several vaccines against the SARS-CoV-2 virus have been developed. Objective: To estimate the proportion of newborns who acquire IgG anti-SARS-CoV-2 antibodies from mothers vaccinated against COVID-19. Methods: Eligible study subjects seeking care in the Obstetrics & Gynecology department for delivery were recruited in this cross-sectional analytic study. Demographic and clinical characteristics of the study subjects were noted and around 3–5 mL venous blood was collected from each study participant duo (mother and newborn) to detect IgG antibodies to SARS-CoV2 “S” protein. Results: Over the entire study period, 125 pregnant ladies who were vaccinated with two doses of any COVID-19 vaccine were included in the study. A sizeable proportion (44.0%) of vaccinated pregnant women were seropositive for IgG antibodies to SARS-CoV2 “S” protein. A significantly high number of seropositive newborns (82.8%) were delivered to seropositive mothers as compared to seronegative mothers (OR 41.1; 95% confidence interval 14.6–116.1, p < .0001). Conclusions: The present study reveals that a substantial proportion of newborns acquired SARS-CoV-2 antibodies from their vaccinated seropositive mothers through transplacental transfer.

Maternal Seroprevalence and Placental Transfer of COVID-19 Antibodies in Pregnancy: A Hospital-Based Study.

Coronavirus disease 2019 (COVID-19) is a relatively new disease with high morbidity and mortality.Information about the prevalence of infections in pregnancy could help identify herd immunity, project epidemics, and decide policy guidelines. The aim of this study was to determine the infection susceptibility risk of COVID-19 in pregnancy, to determine the prevalence of COVID-19 antibodies (IgG & IgM), and to evaluate the determinants of COVID-19 antibody positivity in pregnancy. This was an analytical cross-sectional study involving 258 consenting pregnant women recruited at Irrua Specialist Teaching Hospital, Edo State, Nigeria. Of these, 179 participants were recruited from the antenatal clinic, and 79 from the gynecology emergency unit. A structured questionnaire was administered at baseline. Venous blood was obtained at enrolment to test for total antibodies using ELISA. A nasopharyngeal swab was simultaneously obtained for COVID-19 PCR for all participants. Umbilical cord blood was taken after delivery in those who had positive serology. Socio-demographic variables and clinical presentation of respondents were considered as exposure variables, and this was cross-tabulated with outcome variables in bivariate analysis using chi-square with a level of significance at a P-value less than 0.05. Variables in bivariate analysis of chi-square that have a P-value less than 0.2 were entered into a logistic regression using multivariate logistic models. The study detected active COVID-19 infections among 7.4% (19/258) of the study participants. The study demonstrated a seroprevalence of COVID-19 antibodies in 62.4% (161/258) of the participants at recruitment and showed a strong correlation between working in the healthcare setting and living in an urban environment. Our study also reported 5.3% (8/152) of cord blood antibody positivity among study participants. The concentration of maternal immunoglobulin strongly and positively correlated with cord blood seropositivity. Prevalence estimates are an underestimate of the actual proportion of pregnant women with prior COVID-19 exposure as observed in the study discrepancy of confirmed PCR infection and evidence of previous infection from serology. The study also highlighted a low efficiency of placental transfer of COVID-19 antibodies at birth among those who were seropositive at baseline and showed that maternal antibody levels play an important role in determining the efficiency of placenta transfer of COVID-19 antibodies in pregnancy.

A stockpile of neonatal antibodies pertaining to SARS Covid (COVID 19) ascertained in cord blood after complete vaccination of covishield in mother- An observational study

Maternal antibodies are a vital component of neonatal immunity. These antibodies give the baby a head start in building their immune system and fighting off diseases. The study was carried out to check the presence of IgG antibodies in cord blood of a completely vaccinated mother with Covishield and to find out if any side effects occurred during their vaccination. It was clear from the study that all the cord blood samples showed presence of antibodies and only limited side effects were observed in the vaccinated mothers. An observational study was done in the gynecology department of a tertiary care hospital in Trivandrum from November 2022 to April 2023 (6 months duration) with 40 cord blood samples taken from completely vaccinated mothers. A total of 40 women were included who had completed two doses of Covishield vaccine. Presence of umbilical cord blood IgG was found in all the 40 samples, i.e. Covid IgG > 17.8 BAU/mL. Among the 40 samples, 75% of them had not experienced any side effects after their vaccination while the remaining 25% had experienced minor side effects.The findings made from this study can be used to prove that vaccines are capable of producing antibodies in mother which will be transferred to her baby through the cord blood. It is also evident that the vaccine has produced only minor side effects.

Immunogenicity and reactogenicity of heterologous COVID-19 vaccination in pregnant women

ABSTRACT This open-labeled non-inferiority trial evaluated immunogenicity and reactogenicity of heterologous and homologous COVID-19 vaccination schedules in pregnant Thai women. 18–45-year-old pregnant women with no history of COVID-19 infection or vaccination and a gestational age of ≥12 weeks were randomized 1:1:1 into three two-dose primary series scheduled 4 weeks apart: BNT162b2-BNT162b2 (Group 1), ChAdOx1-BNT162b2 (Group 2), and CoronaVac-BNT162b2 (Group 3). Serum antibody responses, maternal and cord blood antibody levels at delivery, and adverse events (AEs) following vaccination until delivery were assessed. The 124 enrolled participants had a median age of 31 (interquartile range [IQR] 26.0–35.5) years and gestational age of 23.5 (IQR 18.0–30.0) weeks. No significant difference in anti-receptor binding domain (RBD) IgG were observed across arms at 2 weeks after the second dose. Neutralizing antibody geometric mean titers against the ancestral Wuhan strain were highest in Group 3 (258.22, 95% CI [187.53, 355.56]), followed by Groups 1 (187.47, 95% CI [135.15, 260.03]) and 2 (166.63, 95% CI [124.60, 222.84]). Cord blood anti-RBD IgG was correlated with, and equal to or higher than, maternal levels at delivery (r = 0.719, P < .001) and inversely correlated with elapsed time after the second vaccination (r = −0.366, P < .001). No significant difference in cord blood antibody levels between groups were observed. Local and systemic AEs were mild-to-moderate and more frequent in Group 2. Heterologous schedules of CoronaVac-BNT162b2 or ChAdOx1-BNT162b2 induced immunogenicity on-par with BNT162b2-BNT162b2 and may be considered as alternative schedules for primary series in pregnant women in mRNA-limited vaccine settings.

Cord blood antibodies following BBIBP-CorV (Sinopharm) vaccination during pregnancy.

This study aimed to evaluate the maternal and umbilical cord blood antibody levels, after COVID vaccination during pregnancy. The women who received the COVID-19 vaccine (Sinopharm) during pregnancy were included. Maternal and cord blood samples were tested to detect the severe acute respiratory syndrome coronavirus 2 receptor binding domain (RBD) specific antibodies. In addition, obstetric information and side effects after vaccination were gathered. A total of 23 women were included. Eleven pregnant women took two doses and 12 cases received a single dose of the vaccine. No IgM antibody was detected in any maternal blood or cord blood samples. The RBD-specific Immunoglobulin G (IgG) antibody was positive in mothers receiving 2 doses of the vaccine and their infants. But the antibody titers were under the positive cut-off threshold for the other 12 women who were vaccinated with a single dose. Women who received both doses of vaccine had significantly higher IgG levels than a single dose of Sinopharm (p = .025). The same result was demonstrated in infants born to these mothers (p = .019). There was a significant correlation between maternal and neonatal IgG concentrations. Although, receiving both doses of the BBIBP-CorV vaccine (not 1 dose) during pregnancy is highly beneficial for increasing humoral immunity for the mother and fetus.

Pilot Study for Immunogenicity of SARS-CoV-2 Vaccine with Seasonal Influenza and Pertussis Vaccines in Pregnant Women.

Background: It is well known that the implementation of routine immunizations to prevent vaccine-preventable diseases has a significant impact on the health and well-being of infants, children, and pregnant women. We aimed to evaluate the influence of influenza, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine on the immunogenicity of SARS-CoV-2 vaccine among pregnant women, the priority population recommended for vaccination. Methods: We conducted a prospective study among pregnant women without previous SARS-CoV-2 infection in Taiwan. Maternal and umbilical cord blood samples at delivery were analyzed for the percentage of inhibition of neutralizing antibodies (NAbs) against the original strain, Delta, and Omicron variants of SARS-CoV-2 as well as the total antibody to the SARS-CoV-2 spike protein. We examined the association between different doses of SARS-CoV-2 vaccine in combination with influenza and Tdap vaccination, and two-dose SARS-CoV-2 vaccination with or without influenza and Tdap vaccines via a two-sample t-test. Results of p < 0.05 were considered to be statistically significant. Results: 98 pregnant women were enrolled in our study, with 32 receiving two doses of SARS-CoV-2 mRNA-1273 vaccine, 60 receiving three-dose of mRNA-1273, and 6 receiving one-dose of ChAdOx1 and two-dose of mRNA-1273. Twenty-one participants were immunized with SARS-CoV-2, influenza, and Tdap vaccines. Of these 21 individuals, there were no significant NAbs levels in maternal and cord blood samples against the Omicron variant, regardless of doses or type of SARS-CoV-2 vaccine. However, antibody responses against the wild-type and Delta variant were significantly lower in all maternal sera in the two-dose SARS-CoV-2 vaccine group. Among 32 women receiving two-dose mRNA-1273, significantly lower levels of NAbs in maternal sera were observed against the Delta variant and total antibody both in maternal sera and cord blood were observed in individuals receiving SARS-CoV-2 and influenza vaccine. Conclusion: This is the pilot study to demonstrate the effects of influenza and the Tdap vaccine on the immunogenicity of the SARS-CoV-2 vaccine among pregnant women. These results suggest that combination vaccination during pregnancy may result in immunogenic interactions.

2129. Maternal Transmission of SARS-CoV-2-specific Antibodies, but not Cytokines/Chemokines to Neonates Following Infection and Vaccination During Pregnancy

Abstract Background Despite extensive studies of human immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) vaccination, research examining protective correlates of vertical transmission following maternal exposure in pregnancy remain limited. Here, we characterized antibody and cytokine responses in maternal and cord blood following infection or vaccination at various timepoints during gestation. Methods Spike S1 protein-specific binding antibodies and antibodies capable of blocking the interaction between the receptor binding domain (RBD) and the angiotensin converting enzyme 2 (ACE2) were measured in maternal and cord blood by ELISA. Serum concentrations of 74 cytokines/chemokines were measured by multiplex assay. Humoral responses and cytokine levels from matched maternal and fetal cord sera were compared and examined for potential correlations. Results We observed a highly significant correlation between Spike S1-specific antibody titer and RBD-ACE2 blocking antibody activity between maternal and fetal cord serum (p &amp;lt; 2.2e-16, R &amp;gt; 0.90). Blocking antibody activity was significantly higher for mothers infected during the 3rd trimester compared to earlier trimesters; however, vaccinated mothers developed and transferred higher antibody titers with greater RBD-ACE2 blocking antibody activity to their neonates than infected mothers. Furthermore, vaccine-induced Spike S1 IgG transfer ratios (fetal cord/maternal) were significantly higher than those induced by infection (p = 0.002). Multiplex assay showed significantly elevated levels of 33 cytokines/chemokines, mainly pro-inflammatory in infected maternal serum samples, while the paired fetal cord samples exhibited an anti-inflammatory cytokine predominance. Conclusion Our data support selective vertical transmission of potentially protective humoral responses against SARS-CoV-2, especially following vaccination in the 3rd trimester. The anti-inflammatory cytokine predominance in cord blood that persists despite maternal SARS-CoV-2 infection may offset the adverse outcomes of inflammation in pregnancy for the neonate. Disclosures All Authors: No reported disclosures.

577. Cord Blood Protective Antibodies Seroprevalence against Diphtheria, Pertussis, Measles, Mumps and Rubella at Birth among Healthy Term Indian Neonates

Abstract Background The resurgence of vaccine preventable diseases in young infants is a matter of concern worldwide. Cord blood antibodies seroprevalence against various vaccine preventable diseases could reflect protection rates among adults, which could be important in providing protection in early infancy of newborn baby. Tdap vaccination is not yet part of immunization program for pregnant women in India. Methods Apparently healthy term newborns, delivered at a tertiary care hospital in Northern India, over two-year period were enrolled after taking informed written consent from their parents, and their cord blood sample was collected at birth. Ethical clearance was obtained from Institute Ethics Committee before starting enrollment. Results A total of 160 newborns (M:F=86:74) were enrolled. In our study, antibodies (IgG) against diphtheria toxin (DT) were &amp;gt;0.1 IU/ml in 44.4% (71/160), 0.01 to 0.1 IU/ml in 53.1% (85/160) and &amp;lt; 0.01 IU/ml in 2.5% (4/160). Only 44.4% of them were fully protected at birth against diphtheria. Antibodies (IgG) against pertussis toxin (PT) &amp;gt;40 U/ml were seen in 41.2% (66/160). Out of these 66 children, 23 had titers &amp;gt;100 U/ml. Total of 58.8% (94/160) children had antibodies &amp;lt; 40 U/ml. Out of these 94 children, 48 had titers &amp;lt; 20 U/ml. Since correlates of protection in pertussis are not defined; those having titers &amp;gt;100 U/ml i.e. 14.3% were most protected; while those having titers &amp;lt; 20 U/ml were least protected. Antibodies (IgG) against measles antigen were &amp;gt;12 IU/ml in 88.8% (142/160). Antibodies (IgG) against mumps antigen were &amp;gt;12 IU/ml in 83.1% (133/160). Antibodies (IgG) against rubella antigen were &amp;gt;12 IU/ml in 83.7% (134/160). Conclusion Protective antibodies against diphtheria and pertussis toxins were less in the studied newborns at birth making them susceptible to these diseases in early infancy, before primary vaccination commences. Tdap vaccination for pregnant mothers in India could help in improving these titers and protection in early infancy. Protective antibodies against measles, mumps and rubella in studied newborns at birth were satisfactory. For further enhancing protection, especially against rubella, one dose of MMR vaccine may be advised for women in child bearing age. Acknowledgement: PGI Intramural Research Grant Disclosures All Authors: No reported disclosures.

Detectable Antibodies in Newborn Cord Blood Following Maternal COVID-19 Infection Before Pregnancy: A Case Report

: In this report, we present a case of an infant with detectable antibodies in the umbilical cord blood who was born to a healthcare professional mother diagnosed with coronavirus disease 2019 (COVID-19) before pregnancy and recovered, and also discuss the antibody level in light of relevant literature. Data consisted of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) polymerase chain reaction (PCR) test and negative pre-pregnancy repeat real-time polymerase chain reaction (RT-PCR) test of a 29-year-old medical doctor mother, follow-up antibody test results in pregnancy, and antibodies detected in the cord blood of the newborn after birth. The study data were collected through face-to-face interviews with the mother. In conclusion, this case shows that SARS-CoV-2 immunoglobulin G (IgG) antibodies can be detected in the baby’s cord blood immediately after birth from a mother who was diagnosed with COVID-19 before becoming pregnant and subsequently recovered with pharmacological treatment.

SARS-CoV-2 IgG Antibody Levels in Women with IBD Vaccinated during Pregnancy.

Regulatory agencies supported vaccination of pregnant women with SARS-CoV-2 mRNA vaccines, including patients with IBD. No data exist regarding these vaccines in IBD during pregnancy. To assess the serologic response to two doses of the mRNA SARS-CoV-2 BNT162b2 vaccine in pregnant women with IBD vaccinated during pregnancy, compared to that of pregnant women without IBD, and non-pregnant women with IBD. Anti-spike antibody levels were assessed in all women and in cord blood of consenting women. From December 2020 to December 2021, 139 women were assessed: pregnant with IBD-36, pregnant without IBD-61, and not pregnant with IBD-42. Antibodies were assessed in cords of two and nine newborns of women with and without IBD, respectively. Mean gestational ages at administration of the second vaccine doses were 22.0 weeks in IBD and 23.2 weeks in non-IBD, respectively. Mean (SD) duration from the second vaccine dose to serology analysis in pregnant women with IBD, without IBD, and in non-pregnant women with IBD was 10.6 (4.9), 16.4 (6.3), and 4.3 (1.0) weeks, respectively. All women mounted a serologic response. In multivariable analysis, no correlation was found between the specific group and antibody levels. In both pregnancy groups, an inverse correlation between antibody levels and the interval from the second vaccine dose was demonstrated. Cord blood antibody levels exceeded maternal levels in women with and without IBD. All patients with IBD mounted a serologic response. The interval between vaccine administration to serology assessment was the most important factor determining antibody levels. A third vaccine dose should be considered in pregnant women with IBD vaccinated at early stages of pregnancy.

Detection of SARS-CoV-2 Neutralizing Antibodies in Vaccinated Pregnant Women and Neonates by Using a Lateral Flow Immunoassay Coupled with a Spectrum-Based Reader.

The focus of this study was to investigate the detection of neutralizing antibodies (Nabs) in maternal serum and cord blood as the targeted samples by employing a lateral flow immunoassay combined with a spectrum reader (LFI-SR) and the correlation of Nab protection against different types of SARS-CoV-2. We enrolled 20 pregnant women who were vaccinated with the Moderna (mRNA-1273) vaccine during pregnancy and collected 40 samples during delivery. We used an LFI-SR for the level of spike protein receptor binding domain antibody (SRBD IgG) as Nabs and examined the correlation of the SRBD IgG concentration and Nab inhibition rates (NabIR) via enzyme-linked immunosorbent assays (ELISA). The LFI-SR had high confidence for the SRBD IgG level (p < 0.0001). Better NabIR were found in wild-type SARS-CoV-2 (WT) compared to Delta-type (DT) and Omicron-type (OT). Women with two-dose vaccinations demonstrated greater NabIR than those with a single dose. The cut-off value of the SRBD IgG level by the LFI-SR for NabIR to DT (≥30%; ≥70%) was 60.15 and 150.21 ng/mL for mothers (both p = 0.005), and 156.31 (p = 0.011) and 230.20 ng/mL (p = 0.006) for babies, respectively. An additional vaccine booster may be considered for those mothers with SRBD IgG levels < 60.15 ng/mL, and close protection should be given for those neonates with SRBD IgG levels < 150.21 ng/mL, since there is no available vaccine for them.

Placental Injury and Antibody Transfer after Coronavirus Disease 2019 in Pregnancy.

BackgroundWe examined the relationship between placental histopathology and transplacental antibody transfer in pregnant patients after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.MethodsDifferences in plasma concentrations of anti-receptor biding domain (RBD) immunoglobulin (Ig)G antibodies in maternal and cord blood were analyzed according to presence of placental injury.ResultsMedian anti-RBD IgG concentrations in cord blood with placental injury (n = 7) did not differ significantly from those without injury (n = 16) (median 2.7 [interquartile range {IQR}, 1.8–3.6] vs 2.7 [IQR, 2.4–2.9], P = 0.59). However, they were associated with lower transfer ratios (median 0.77 [IQR, 0.61–0.97] vs 0.97 [IQR, 0.80–1.01], P = 0.05).ConclusionsSARS-CoV-2 placental injury may mediate reduced maternal-fetal antibody transfer.

The Impact of Timing of Pertussis Vaccination During Pregnancy on Infant Antibody Levels at Birth: A Multi-Country Analysis.

BackgroundPertussis vaccination during pregnancy is an effective strategy at reducing pertussis-related morbidity and mortality in infancy and is recommended across several countries. However, the optimal timepoint for vaccination in pregnancy to afford maximal protection to newborns is yet to be elucidated. This multi-country analysis aimed to model the impact of timing of vaccination during pregnancy on infant antibody titers at birth.MethodsA multi-country analysis on a cohort of mother-infant pairs (n=698) vaccinated between 19.6-37.1 weeks gestation was conducted. Data taken from four parent studies on pertussis vaccination during pregnancy were modelled using natural cubic splines and linear mixed models to study the association of both gestational age at vaccination and the interval between vaccination and delivery with pertussis-specific cord blood antibody levels after pertussis vaccination during pregnancy.ResultsTerm born infants on average achieve the highest antibody levels at birth if women are vaccinated before 31 weeks’ gestation. When considering both term and preterm deliveries, an interval of at least 7.5 weeks between vaccination and delivery is required to achieve the highest cord blood antibody levels. The models show that vaccinating earlier than these timeframes will also provide the infant with equally high antibody levels at birth.ConclusionsVaccinating in the second and early third trimester results in the highest antibody levels at birth. Vaccinating earlier within this window is needed to provide equal benefits to both term and preterm born infants.

Risk of vertical transmission of SARS CoV-2 infection to neonates born to covid positive mothers: A pilot study from a tertiary care hospital of North India

ObjectivesTo assess the risk of neonatal SARS-CoV-2 infection born to the women with confirmed SARS-CoV-2 infection. Materials and methodsThis prospective study was conducted at single tertiary hospital from September 2020 and May 2021. 50 pregnant women with confirmed SARS-CoV-2 infection and 50 neonates were included for analysis. We performed comprehensive testing of all biological samples for vertical transmission including the cord blood immunoglobulin. ResultsWe detected SARS-CoV-2 in one fetal membrane and one amniotic fluid sample. We also demonstrated presence of anti-SARS-CoV-2 IgM antibodies in cord blood of 3 neonates. Though none of the samples of vaginal secretion, breast milk and nasopharyngeal swab from neonates were tested positive for covid infection via RT-PCR. We demonstrated presence of anti-SARS-CoV-2 IgG antibodies in the cord blood which had shown positive correlation with increasing disease to delivery interval and disease severity. ConclusionVertical transmission of SARS-CoV-2 is possible. As virus was not detected in cervicovaginal secretions and breast milk so vertical transmission through this mechanism seems unlikely. Presence of IgG in cord blood is suggestive of passive immunity acquired from mother. This finding has greater clinical implication as large number of expecting mothers are being vaccinated.

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

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. 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). 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. 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.

Vertical Transmission of SARS-CoV-2 during Pregnancy: A Prospective Italian Cohort Study.

The extent of vertical transmission (VT) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from mothers their fetuses or neonates is still uncertain. We aimed to determine the incidence of VT. In this prospective cohort study. All mother diagnosed with SARS-CoV-2 infection at the time of delivery or up to 1 week prior and their neonates, managed in a tertiary referral hospital for pregnancy complicated by coronavirus disease 2019 (COVID-19) in Rome, from April 2 to December 22, 2020, were included. Maternal infection was defined as nasopharyngeal swab test results positive for SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR). Biological samples were collected before, at, and after delivery to test positivity for SARS-CoV-2 RT-PCR and anti-SARS-CoV-2-specific antibodies. The cohort included 95 women and 96 neonates with documented SARS-CoV-2 test results. Four neonates (4.2%) tested positive. The incidence of VT, according to the guidance criteria for diagnosing perinatal SARS-CoV-2 infection, was 5.2%. Neonatal symptoms were due to prematurity or fetal distress: symptomatic infants had lower median (min-max) gestational age, 38.1 (29.3-40.6) versus 39.3 (33.9-41.9) weeks (p = 0.036), and 1-minute and 5-minute Apgar scores, 9 (3-9) versus 9 (7-10) (p = 0.036) and 10 (6-10) versus 10 (8-10) (p = 0.012), respectively, than asymptomatic infants and needed more frequent assistance in the delivery room (22.2 vs 2.5%; p = 0.008). Only six (7.1%) neonates had anti-SARS-CoV-2-specific antibodies, despite the ongoing maternal infection. The incidence of VT is low as is the detection of specific anti-SARS-CoV-2 antibodies in cord blood when infection is contracted late in pregnancy. This would suggest poor protection of infants against horizontal transmission of the virus. · VT of SARS-CoV-2 from pregnant mothers to fetuses or neonates can be possible.. · In this prospective cohort study, the incidence of VT is found to be 5.2%.. · VT is low but exists..

COVID-19 vaccines in pregnancy.

COVID-19 caused by SARS-CoV-2 coronavirus has been associated with severe illness in pregnant women. Furthermore, COVID-19 during pregnancy is associated with adverse fetal outcomes including preterm labor. Pregnant women were largely excluded from initial clinical trials investigating the safety and efficacy of COVID-19 vaccines; however, they have since been included as part of the routine roll-out of these vaccines. This narrative review synthesizes the evidence on the safety, immunogenicity, and effectiveness predominantly of the mRNA COVID-19 vaccines which have been most widely used in pregnant women.

Antibody Response and Maternofetal Antibody Transfer in SARS-CoV-2-Positive Pregnant Women: A Multicenter Observational Study

Introduction Awareness of SARS-CoV-2 infection in pregnant women and the potential risk for infection of their neonates is increasing. The aim of this study was to examine the immune status of affected women and evaluate the dynamics of placental antibody transfer. Materials and Methods The study included 176 women with SARS-CoV-2 infection during pregnancy who delivered between April 2020 and December 2021 at eight obstetric maternity sites. Demographic data, maternal and neonatal characteristics were summarized. Antibody testing for IgA and IgG in maternal blood sera and umbilical cord samples was evaluated and IgG transfer ratios were calculated. Values were related to the time of infection during pregnancy and birth. Results The percentage of IgG positive women increased from 29.0% (95% CI 23.8 – 37.8) at presentation with a positive PCR test result to 75.7% (95% CI 71.6 – 79.8), the percentage of IgG positive umbilical cord blood samples increased from 17.1% (95% CI 13.0 – 21.3) to 76.4% (95% CI 72.2 – 80.7) at more than six weeks after infection. Regression lines differed significantly between maternal and fetal IgG responses (p < 0.0001). Newborns react with a latency of about one week; umbilical cord blood antibody concentrations are highly correlated with maternal concentration levels (ρ = 0.8042; p < 0.0001). IgG transplacental transfer ratios were dependent on infection-to-birth interval. Two of the umbilical cord blood samples tested positive for IgA. Conclusions These findings confirm vertical SARS-CoV-2 transmission is rare; however, antibodies are transferred to the fetus soon after infection during pregnancy. Since transplacental antibody transfer might have a protective value for neonatal immunization this information may be helpful when counseling affected women.