Early Adverse Events and Immune Response Following Second and Third COVID-19 Vaccination in Pregnancy

A scoping review of active, participant centred, digital adverse events following immunization (AEFI) surveillance of WHO approved COVID-19 vaccines: A Canadian immunization Research Network study

This scoping review examines the role of digital solutions in active, participant-centered surveillance of adverse events following initial release of COVID-19 vaccines. The goals of this paper were to examine the existing literature surrounding digital solutions and technology used for active, participant centered, AEFI surveillance of novel COVID-19 vaccines approved by WHO. This paper also aimed to identify gaps in literature surrounding digital, active, participant centered AEFI surveillance systems and to identify and describe the core components of active, participant centered, digital surveillance systems being used for post-market AEFI surveillance of WHO approved COVID-19 vaccines, with a focus on the digital solutions and technology being used, the type of AEFI detected, and the populations under surveillance. The findings highlight the need for customized surveillance systems based on local contexts and the lessons learned to improve future vaccine monitoring and pandemic preparedness.

Safety of COVID-19 Vaccination in Pregnancy: A Systematic Review

The COVID-19 pandemic has posed significant risks to pregnant women and those recently pregnant, leading to heightened mortality and morbidity rates. Vaccination has emerged as a pivotal strategy in reducing COVID-19-related deaths and illnesses worldwide. However, the initial exclusion of pregnant individuals from most clinical trials raised concerns about vaccine safety in this population, contributing to vaccine hesitancy. This review aims to consolidate the existing literature to assess the safety and efficacy of COVID-19 vaccination in pregnant populations and neonatal outcomes. Diverse studies were included evaluating various aspects of safety for women and their newborns, encompassing mild to severe symptoms across different vaccines. The findings indicate the overall safety and efficacy of COVID-19 vaccination, with minimal adverse outcomes observed, including mild side effects like pain and fever. Although most studies reported the absence of severe adverse outcomes, isolated case reports have raised concerns about potential associations between maternal COVID-19 vaccination and conditions such as fetal supraventricular tachycardia and immune-mediated diseases. Our review underscores the importance of ongoing surveillance and monitoring to ensure vaccine safety in pregnant women. Overall, COVID-19 vaccination during pregnancy remains a safe and effective strategy, emphasizing the need for continued research and vigilance to safeguard maternal and fetal health.

COVID-19 vaccination during pregnancy and adverse perinatal outcomes: a systematic review and meta-analysis

We aimed to estimate the associations between coronavirus disease 2019 (COVID-19) vaccination during pregnancy and the risks of adverse perinatal outcomes. We performed a literature search in PubMed, Web of Science and Embase to identify eligible studies published up to 24 September 2023, yielding 39 included studies. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated with a random effects model. The pooled results showed that COVID-19 vaccination during pregnancy (any type or dose of COVID-19 vaccination during any trimester) was not associated with an increased risk of adverse perinatal outcomes. In particular, COVID-19 vaccination in the third trimester was associated with a decreased risk of preterm birth (<37 weeks) (RR 0.85 [95% CI 0.74 to 0.98]), 5-min Apgar <7 (RR 0.87 [95% CI 0.78 to 0.97]) and neonatal intensive care unit (NICU) admission (RR 0.90 [95% CI 0.86 to 0.95]). The inverse associations were also found in analysis of one-dose vaccination during pregnancy and the risk of miscarriage (RR 0.83 [95% CI 0.72 to 0.96]) and preterm birth (<37 weeks) (RR 0.90 [95% CI 0.80 to 1.00]) and two-dose vaccination during pregnancy and the risk of NICU admission (RR 0.86 [95% CI 0.76 to 0.96]). COVID-19 vaccination during pregnancy does not increase the risk of negative outcomes for the mother or baby.

Defining and reporting adverse events of special interest in comparative maternal vaccine studies: a systematic review

Introduction

The GAIA (Global Alignment on Immunisation Safety Assessment in Pregnancy) consortium was established in 2014 with the aim of creating a standardised, globally coordinated approach to monitoring the safety of vaccines administered in pregnancy. The consortium developed twenty-six standardised definitions for classifying obstetric and infant adverse events. This systematic review sought to evaluate the current state of adverse event reporting in maternal vaccine trials following the publication of the case definitions by GAIA, and the extent to which these case definitions have been adopted in maternal vaccine safety research.

Methods

A comprehensive search of published literature was undertaken to identify maternal vaccine research studies. PubMed, EMBASE, Web of Science, and Cochrane were searched using a combination of MeSH terms and keyword searches to identify observational or interventional studies that examined vaccine safety in pregnant women with a comparator group. A two-reviewer screening process was undertaken, and a narrative synthesis of the results presented.

Results

14,737 titles were identified from database searches, 435 titles were selected as potentially relevant, 256 were excluded, the remaining 116 papers were included. Influenza vaccine was the most studied (25.0%), followed by TDaP (20.7%) and SARS-CoV-2 (12.9%).Ninety-one studies (78.4%) were conducted in high-income settings. Forty-eight (41.4%) utilised electronic health-records. The majority focused on reporting adverse events of special interest (AESI) in pregnancy (65.0%) alone or in addition to reactogenicity (27.6%). The most frequently reported AESI were preterm birth, small for gestational age and hypertensive disorders. Fewer than 10 studies reported use of GAIA definitions. Gestational age assessment was poorly described; of 39 studies reporting stillbirths 30.8% provided no description of the gestational age threshold.

Conclusions

Low-income settings remain under-represented in comparative maternal vaccine safety research. There has been poor uptake of GAIA case definitions. A lack of harmonisation and standardisation persists limiting comparability of the generated safety data.

Effectiveness and safety of COVID-19 vaccines on maternal and perinatal outcomes: a systematic review and meta-analysis

OBJECTIVE

To assess the effects of COVID-19 vaccines in women before or during pregnancy on SARS-CoV-2 infection-related, pregnancy, offspring and reactogenicity outcomes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Major databases between December 2019 and January 2023.

STUDY SELECTION

Nine pairs of reviewers contributed to study selection. We included test-negative designs, comparative cohorts and randomised trials on effects of COVID-19 vaccines on infection-related and pregnancy outcomes. Non-comparative cohort studies reporting reactogenicity outcomes were also included.

QUALITY ASSESSMENT, DATA EXTRACTION AND ANALYSIS

Two reviewers independently assessed study quality and extracted data. We undertook random-effects meta-analysis and reported findings as HRs, risk ratios (RRs), ORs or rates with 95% CIs.

RESULTS

Sixty-seven studies (1 813 947 women) were included. Overall, in test-negative design studies, pregnant women fully vaccinated with any COVID-19 vaccine had 61% reduced odds of SARS-CoV-2 infection during pregnancy (OR 0.39, 95% CI 0.21 to 0.75; 4 studies, 23 927 women; I2=87.2%) and 94% reduced odds of hospital admission (OR 0.06, 95% CI 0.01 to 0.71; 2 studies, 868 women; I2=92%). In adjusted cohort studies, the risk of hypertensive disorders in pregnancy was reduced by 12% (RR 0.88, 95% CI 0.82 to 0.92; 2 studies; 115 085 women), while caesarean section was reduced by 9% (OR 0.91, 95% CI 0.85 to 0.98; 6 studies; 30 192 women). We observed an 8% reduction in the risk of neonatal intensive care unit admission (RR 0.92, 95% CI 0.87 to 0.97; 2 studies; 54 569 women) in babies born to vaccinated versus not vaccinated women. In general, vaccination during pregnancy was not associated with increased risk of adverse pregnancy or perinatal outcomes. Pain at the injection site was the most common side effect reported (77%, 95% CI 52% to 94%; 11 studies; 27 195 women).

CONCLUSION

COVID-19 vaccines are effective in preventing SARS-CoV-2 infection and related complications in pregnant women.

PROSPERO REGISTRATION NUMBER

CRD42020178076.

Incidence and Nature of Short-Term Adverse Events following COVID-19 Second Boosters: Insights from Taiwan's Universal Vaccination Strategy

This study evaluates the incidence and characteristics of adverse events (AEs) following the second COVID-19 booster dose, leveraging Taiwan's distinctive approach of extending booster vaccinations to all citizens, unlike the targeted high-risk group strategies in other countries. Utilizing data from Taipei Veterans General Hospital's Vaccine Adverse Event Reporting System (VAERS) from 27 October 2022 to 19 January 2023, this research examines AEs in 441 out of 1711 booster recipients, considering factors like age, vaccine brands, and booster combinations. The findings revealed incidence rates (IRs) of 25.6% (95% CI: 21.1-30.8) after the first booster and 24.9% (95% CI: 20.5-30.0) after the second, mostly non-serious, with those having AEs post-first booster being five times more likely to report them again (incidence rate ratio, 5.02, p < 0.001). Significantly, switching from the mRNA1273 vaccine to another brand reduced AE risk by 18%. This study underscores that AEs are more repetitive than cumulative with additional booster doses, advocating for personalized vaccination strategies based on individual medical histories and previous vaccine reactions. These insights are valuable for healthcare providers in discussing potential AEs with patients, thereby improving vaccine compliance and public trust, and for policymakers in planning future booster vaccination strategies.

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

OBJECTIVE

This study aimed to evaluate the maternal and umbilical cord blood antibody levels, after COVID vaccination during pregnancy.

METHOD

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.

RESULT

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).

CONCLUSION

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.

Maternal and Neonatal Immune Responses Following COVID-19 Infection and Vaccinations in Pregnancy

The objective of the study was to compare the maternal and neonatal humoral immune responses among different groups of women, namely those vaccinated by the BNT162b2 vaccine, not vaccinated, and COVID-19-recovered parturient women at the time of delivery. This is a prospective cohort study of pregnant women, divided into four groups: Group A "Recovered"-recovered and not vaccinated. Group B "Second Vaccination"-first and second doses only. Group C "Third Vaccination"-third dose. Group D "No Third Vaccination"-women eligible for the third dose of the vaccine but did not receive it. Maternal and umbilical cord blood were sampled and tested for SARS-CoV-2 IgG antibodies on admittance to labor and immediately postpartum, respectively. Maternal serum SARS-CoV-2 IgG levels were significantly higher among Group C compared to Group B (741.6 (514.5-1069) vs. 333.5 (327-340.2), respectively). Both groups had higher antibody levels compared to Groups A and D (113.5 (61.62-209.1) and 57.99 (32.93-102.1), respectively). Similarly, umbilical cord blood SARS-CoV-2 IgG levels were also highest among Group C compared to the other three groups (1269 (953.4-1690) vs. Group B, 322.6 (305.6-340.5), Group A, 109 (49.01-242.6), and Group D, 103.9 (48.59-222), respectively). In conclusion, pregnant women who were fully vaccinated with three dosages before delivery generated the highest levels of maternal and neonatal SARS-CoV-2 IgG antibodies.

Complications of COVID-19 Vaccines during Pregnancy; a Systematic Review

INTRODUCTION

Rare serious complications have been documented after COVID-19 vaccination as clinical research proceeded and new target populations, such as children and ‎pregnant women, were included. In this study, we attempted to review the literature relevant to ‎pregnancy complications and maternal outcomes of COVID-19 immunization in pregnant women. ‎.

METHODS

We searched the databases of PubMed, Scopus, Cochrane, and Web of Science on 31 August 2022. The records were downloaded and underwent a two-step screening; 1) title/abstract and then 2) full-text screening to identify the eligible studies. We included English original studies that evaluated the adverse effects of COVID-19 vaccines during pregnancy. Information such as the type of ‎study, geographical location, type of vaccine injected, gestational age, maternal underlying diseases, and ‎complications following the vaccination were extracted into pre-designed tables.

RESULTS

According to the findings of included studies, in most of them vaccination had a positive impact and no negative effects were observed. Also, no medical history was reported in 11 articles, and pregnant women had no underlying diseases. Some serious adverse events were reported after ‎vaccination, including miscarriage, paresthesia, uterine contraction, vaginal bleeding, preterm birth, major ‎congenital anomalies, intrauterine growth restriction, and seizure. ‎.

CONCLUSION

Because of limited data availability and the cross-sectional design of most studies, we could neither infer ‎causation between vaccines and incidence of adverse effects nor comment with certainty about any ‎possible adverse outcome of COVID-19 vaccines in vaccinated pregnant women. Consequently, more longitudinal and experimental studies are needed to define the exact adverse effects of COVID-19 vaccines in pregnant women.