SARS-CoV-2 positivity in offspring and timing of mother-to-child transmission: living systematic review and meta-analysis

SARS-CoV-2 (COVID-19) as a possible risk factor for neurodevelopmental disorders

Pregnant women constitute one of the most vulnerable populations to be affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the cause of coronavirus disease 2019. SARS-CoV-2 infection during pregnancy could negatively impact fetal brain development via multiple mechanisms. Accumulating evidence indicates that mother to fetus transmission of SARS-CoV-2 does occur, albeit rarely. When it does occur, there is a potential for neuroinvasion via immune cells, retrograde axonal transport, and olfactory bulb and lymphatic pathways. In the absence of maternal to fetal transmission, there is still the potential for negative neurodevelopmental outcomes as a consequence of disrupted placental development and function leading to preeclampsia, preterm birth, and intrauterine growth restriction. In addition, maternal immune activation may lead to hypomyelination, microglial activation, white matter damage, and reduced neurogenesis in the developing fetus. Moreover, maternal immune activation can disrupt the maternal or fetal hypothalamic-pituitary-adrenal (HPA) axis leading to altered neurodevelopment. Finally, pro-inflammatory cytokines can potentially alter epigenetic processes within the developing brain. In this review, we address each of these potential mechanisms. We propose that SARS-CoV-2 could lead to neurodevelopmental disorders in a subset of pregnant women and that long-term studies are warranted.

The Essentials about Neonatal Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Coronavirus Disease: A Narrative Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can occur in neonates as the virus can be transmitted both horizontally (from the environment) and vertically (during the pregnancy or at the delivery). Compared to the adult outbreak, neonatal infections do not represent a public health problem. Nonetheless, severe and life-threatening cases may rarely occur and both obstetricians and neonatologists should have a good knowledge of perinatal SARS-CoV-2 infection and related consequences. A high suspicion index must be applied and ruling out neonatal SARS-CoV-2 infection must become a part of the routine clinical workout. Moreover, neonates may be affected by the multisystem inflammatory syndrome, due to a dysregulated host response in the absence of any SARS-CoV-2 infection. We performed a narrative review to summarize here the available literature describing the essentials that should be known by every neonatologist and obstetrician, starting from what has been discovered in 2020 and adding what has been learned in the following years. The paper describes the mechanisms of transmission, clinical features, diagnostic tools, and criteria, as well as possible treatment and prevention strategies. The goal is to provide the practical points to be remembered at the bedside while caring for a pregnant woman or a neonate with suspected or proven coronavirus disease 2019 or multisystem inflammatory syndrome. KEY POINTS: · SARS-CoV-2 neonatal infections occur both vertically (30%) and horizontally (70%).. · Approximately, half of patients do not have clinical manifestations; clinical and laboratory signs are similar to those of adults but usually milder.. · Remdesivir and steroids can be used as a treatment..

Six-Month Outcomes of Infants Born to People With SARS-CoV-2 in Pregnancy

OBJECTIVES

To assess the 6-month incidence of laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, postnatal care, hospitalization, and mortality among infants born to people with laboratory-confirmed SARS-CoV-2 infection during pregnancy by timing of maternal infection.

METHODS

Using a cohort of liveborn infants from pregnancies with SARS-CoV-2 infections in the year 2020 from 10 United States jurisdictions in the Surveillance for Emerging Threats to Mother and Babies Network, we describe weighted estimates of infant outcomes from birth through 6 months of age from electronic health and laboratory records.

RESULTS

Of 6601 exposed infants with laboratory information through 6 months of age, 1.0% (95% confidence interval: 0.8-1.1) tested positive, 19.1% (17.5-20.6) tested negative, and 80.0% (78.4-81.6) were not known to be tested for SARS-CoV-2. Among those ≤14 days of age, SARS-CoV-2 infection occurred only with maternal infection ≤14 days before delivery. Of 3967 infants with medical record abstraction, breastmilk feeding initiation was lower when maternal infection occurred ≤14 days before delivery compared with >14 days (77.6% [72.5-82.6] versus 88.3% [84.7-92.0]). Six-month all-cause hospitalization was 4.1% (2.0-6.2). All-cause mortality was higher among infants born to people with infection ≤14 days (1.0% [0.4-1.6]) than >14 days (0.3% [0.1-0.5]) before delivery.

CONCLUSIONS

Results are reassuring, with low incidences of most health outcomes examined. Incidence of infant SARS-CoV-2, breastmilk feeding initiation, and all-cause mortality differed by timing of maternal infection. Strategies to prevent infections and support pregnant people with coronavirus disease 2019 may improve infant outcomes.

Characteristics and Outcomes of SARS-CoV-2 Positivity in Neonates Born to Mothers with COVID-19 in Klang Valley, Malaysia: A Retrospective Observational Study

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There is a proven risk of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) positivity in neonates born to mothers with coronavirus disease 2019 (COVID-19).

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An increased incidence of prematurity was observed in neonates of mothers with COVID-19.

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Exposure to a mother with COVID-19 post-delivery increases the vertical transmission risk.

Objective

The aim of this study was to analyze the clinical characteristics of neonates born to mothers with coronavirus disease 2019 (COVID-19), along with the incidence and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) positivity in Klang Valley, Malaysia.

Methods

The clinical records of all neonates born to mothers with COVID-19 who were admitted to Sungai Buloh Hospital, Selangor, Malaysia from October 1, 2020 to September 30, 2021 were reviewed retrospectively. Data collected included demographic details and the incidence, risk factors, and clinical outcomes of neonates with SARS-CoV-2 positivity.

Results

A total of 766 neonates from 753 mothers with COVID-19 were included. Overall, 23 (3%) neonates tested positive by nasopharyngeal swab SARS-CoV-2 PCR taken within the first 8 days of life. There were three (0.4%) confirmed and four (0.5%) probable neonatal infections acquired intrapartum, seven (0.9%) confirmed neonatal infections acquired postpartum, and nine (1.2%) cases that did not fit within the classification. The rate of preterm delivery was 25% among all neonates born to mothers with COVID-19 and 39.1% among SARS-CoV-2-positive neonates. Of the SARS-CoV-2-positive neonates, 43.5% required ventilatory support. Factors identified to have a significant association with neonate SARS-CoV-2 positivity included maternal antepartum hemorrhage (odds ratio (OR) 7.33, P = 0.014), place of delivery in a non-designated COVID-19 center (OR 7.64, P < 0.001), exposure to the mother post-delivery (OR 4.13, P = 0.014), and a higher 5-minute Apgar score (score 6–10; OR 0.20, P = 0.0037).

Conclusions

This study identified a risk of SARS-CoV-2 transmission from mothers with COVID-19 to their offspring, with infection acquired predominantly postpartum. A higher incidence of preterm delivery and ventilatory support were observed among SARS-CoV-2-positive neonates.

Observational cohort study of perinatal outcomes of women with COVID-19

BACKGROUND

Understanding the impact of SARS-CoV-2 infection on pregnancy outcomes and of pregnancy on COVID-19 outcomes is critical for ensuring proper prenatal and antenatal care. No similar studies have been published in Saudi Arabia.

METHODS

We performed a prospective cohort study of pregnant women with confirmed SARS-CoV-2 infection who presented at King Faisal Specialist Hospital and Research Center (KFSHRC) in Riyadh, Kingdom of Saudi Arabia. COVID-19 staging was performed, pregnancy-related complications were assessed, and neonatal infection was evaluated.

RESULTS

We enrolled 81 patients (mean age 31.75 years, SD 5.25) of which there were 17 cases in the first trimester, 20 in the second trimester, and 34 in the third trimester. The distribution of COVID-19 severity was 40 patients with Stage A, 36 with Stage B, 4 with Stage C, and 1 with Stage D. Complications were pregnancy loss in 2 patients (one in each first and second trimester) and 1 fetal death after 20 weeks of pregnancy, 7 patients with fetal growth restriction, and 8 with pre-term delivery.

CONCLUSIONS

We did not observe an unusual frequency of pregnancy-related complications due to SARS-CoV-2 infection in this high-risk obstetric population and there was no evidence of vertical transmission in newborns from women who delivered while positive for the virus.

Human early syncytiotrophoblasts are highly susceptible to SARS-CoV-2 infection

Direct in vivo investigation of human placenta trophoblast's susceptibility to SARS-CoV-2 is challenging. Here we report that human trophoblast stem cells (hTSCs) and their derivatives are susceptible to SARS-CoV-2 infection, which reveals heterogeneity in hTSC cultures. Early syncytiotrophoblasts (eSTBs) generated from hTSCs have enriched transcriptomic features of peri-implantation trophoblasts, express high levels of angiotensin-converting enzyme 2 (ACE2), and are productively infected by SARS-CoV-2 and its Delta and Omicron variants to produce virions. Antiviral drugs suppress SARS-CoV-2 replication in eSTBs and antagonize the virus-induced blockage of STB maturation. Although less susceptible to SARS-CoV-2 infection, trophoblast organoids originating from hTSCs show detectable viral replication reminiscent of the uncommon placental infection. These findings implicate possible risk of COVID-19 infection in peri-implantation embryos, which may go unnoticed. Stem cell-derived human trophoblasts such as eSTBs can potentially provide unlimited amounts of normal and genome-edited cells and facilitate coronavirus research and antiviral discovery.

COVID-19 vaccine literacy and vaccine hesitancy among pregnant women and mothers of young children in Japan

BACKGROUND

Delays in the spread of vaccination have been recognized as an urgent public health issue in the context of the COVID-19 pandemic. Vaccine literacy (VL) is a critical determinant of vaccine uptake; however, little is known about VL among pregnant women and mothers of young children.

METHODS

We analyzed data from a nationwide, cross-sectional internet survey in Japan on VL and vaccine hesitancy, conducted with 1,639 pregnant women and 5,688 mothers of young children who had given birth after July 2019, between July 24 and August 30, 2021.

RESULTS

Vaccine hesitancy was observed in 51.1 % of pregnant women and 31.9 % of mothers of young children. The risk of vaccine hesitancy was significantly higher among pregnant women with lower interactive/critical skills (risk ratio [RR] 2.10, 95 % confidence interval [CI] 1.59, 2.78, p < 0.001), although functional skills did not significantly correlate with vaccine hesitancy. For mothers of young children, we found a significantly higher risk of vaccine hesitancy among those with low VL functional skills (RR 1.38, 95 % CI 1.19, 1.61), p < 0.001) and low interactive/critical skills (RR 1.29, 95 % CI 1.10, 1.50, p = 0.001).

CONCLUSIONS

Our findings suggest that aiding individuals to correctly evaluate vaccine-related information is critical for improving vaccine acceptance rates among both pregnant women and mothers of young children. Meanwhile, improving the comprehensibility of communication toolkits may be important for women with children but have a limited effect among pregnant women.

Maternal and Neonatal Outcomes in Pregnant Women With Coronavirus Disease 2019 in Korea

BACKGROUND

This study aimed to describe the maternal, obstetrical, and neonatal outcomes in pregnant women with coronavirus disease 2019 (COVID-19) and identify the predictors associated with the severity of COVID-19.

METHODS

This multicenter observational study included consecutive pregnant women admitted because of COVID-19 confirmed using reverse transcriptase-polymerase chain reaction (RT-PCR) test at 15 hospitals in the Republic of Korea between January 2020 and December 2021.

RESULTS

A total of 257 women with COVID-19 and 62 newborns were included in this study. Most of the patients developed this disease during the third trimester. Nine patients (7.4%) developed pregnancy-related complications. All pregnant women received inpatient treatment, of whom 9 (3.5%) required intensive care, but none of them died. The gestational age at COVID-19 diagnosis (odds ratio [OR], 1.096, 95% confidence interval [CI], 1.04-1.15) and parity (OR, 1.703, 95% CI, 1.13-2.57) were identified as significant risk factors of severe diseases. Among women who delivered, 78.5% underwent cesarean section. Preterm birth (38.5%), premature rupture of membranes (7.7%), and miscarriage (4.6%) occurred, but there was no stillbirth or neonatal death. The RT-PCR test of newborns' amniotic fluid and umbilical cord blood samples was negative for severe acute respiratory syndrome coronavirus 2.

CONCLUSION

At the time of COVID-19 diagnosis, gestational age and parity of pregnant women were the risk factors of disease severity. Vertical transmission of COVID-19 was not observed, and maternal severity did not significantly affect the neonatal prognosis.

Immune Responses to SARS-CoV-2 in Pregnancy: Implications for the Health of the Next Generation

Widespread SARS-CoV-2 infection among pregnant individuals has led to a generation of fetuses exposed in utero, but the long-term impact of such exposure remains unknown. Although fetal infection is rare, children born to mothers with SARS-CoV-2 infection may be at increased risk for adverse neurodevelopmental and cardiometabolic outcomes. Fetal programming effects are likely to be mediated at least in part by maternal immune activation. In this review, we discuss recent evidence regarding the effects of prenatal SARS-CoV-2 infection on the maternal, placental, and fetal immune response, as well as the implications for the long-term health of offspring. Extrapolating from what is known about the impact of maternal immune activation in other contexts (e.g., obesity, HIV, influenza), we review the potential for neurodevelopmental and cardiometabolic morbidity in offspring. Based on available data suggesting potential increased neurodevelopmental risk, we highlight the importance of establishing large cohorts to monitor offspring born to SARS-CoV-2-positive mothers for neurodevelopmental and cardiometabolic sequelae.

SARS-CoV-2 modulates virus receptor expression in placenta and can induce trophoblast fusion, inflammation and endothelial permeability

SARS-CoV-2 is a devastating virus that induces a range of immunopathological mechanisms including cytokine storm, apoptosis, inflammation and complement and coagulation pathway hyperactivation. However, how the infection impacts pregnant mothers is still being worked out due to evidence of vertical transmission of the SARS-CoV-2, and higher incidence of pre-eclampsia, preterm birth, caesarian section, and fetal mortality. In this study, we assessed the levels of the three main receptors of SARS-CoV-2 (ACE2, TMPRSS2 and CD147) in placentae derived from SARS-CoV-2 positive and negative mothers. Moreover, we measured the effects of Spike protein on placental cell lines, in addition to their susceptibility to infection. SARS-CoV-2 negative placentae showed elevated levels of CD147 and considerably low amount of TMPRSS2, making them non-permissive to infection. SARS-CoV-2 presence upregulated TMPRSS2 expression in syncytiotrophoblast and cytotrophoblast cells, thereby rendering them amenable to infection. The non-permissiveness of placental cells can be due to their less fusogenicity due to infection. We also found that Spike protein was capable of inducing pro-inflammatory cytokine production, syncytiotrophoblast apoptosis and increased vascular permeability. These events can elicit pre-eclampsia-like syndrome that marks a high percentage of pregnancies when mothers are infected with SARS-CoV-2. Our study raises important points relevant to SARS-CoV-2 mediated adverse pregnancy outcomes.

Pregnancy and infant outcomes by trimester of SARS-CoV-2 infection in pregnancy-SET-NET, 22 jurisdictions, January 25, 2020-December 31, 2020

OBJECTIVES

We describe clinical characteristics, pregnancy, and infant outcomes in pregnant people with laboratory-confirmed SARS-CoV-2 infection by trimester of infection.

STUDY DESIGN

We analyzed data from the Surveillance for Emerging Threats to Mothers and Babies Network and included people with infection in 2020, with known timing of infection and pregnancy outcome. Outcomes are described by trimester of infection. Pregnancy outcomes included live birth and pregnancy loss (<20 weeks and ≥20 weeks gestation). Infant outcomes included preterm birth (<37 weeks gestation), small for gestational age, birth defects, and neonatal intensive care unit admission. Adjusted prevalence ratios (aPR) were calculated for pregnancy and selected infant outcomes by trimester of infection, controlling for demographics.

RESULTS

Of 35,200 people included in this analysis, 50.8% of pregnant people had infection in the third trimester, 30.8% in the second, and 18.3% in the first. Third trimester infection was associated with a higher frequency of preterm birth compared to first or second trimester infection combined (17.8% vs. 11.8%; aPR 1.44 95% CI: 1.35-1.54). Prevalence of birth defects was 553.4/10,000 live births, with no difference by trimester of infection.

CONCLUSIONS

There were no signals for increased birth defects among infants in this population relative to national baseline estimates, regardless of timing of infection. However, the prevalence of preterm birth in people with SARS-CoV-2 infection in pregnancy in our analysis was higher relative to national baseline data (10.0-10.2%), particularly among people with third trimester infection. Consequences of COVID-19 during pregnancy support recommended COVID-19 prevention strategies, including vaccination.

Unexpected Vertical Transmission of SARS-CoV-2: Discordant Clinical Course and Transmission from Mother to Newborn

Mother-to-newborn COVID-19 transmission is mainly postnatal, but single-case reports and small case series have also described SARS-CoV-2 transplacental transmission. Unfortunately, studies regarding vertical transmission of SARS-CoV-2 lack systematic approaches to diagnosis and classification. So far, scientific evidence seems to suggest that the severity of maternal infection increases the risk of vertical transmission. We report two neonates born from COVID-19-positive mothers, of which one of the newborns had a vertical infection. The placental involvement, and consequent intrauterine transmission of SARS-CoV-2, were inversely related to the severity of the maternal disease. The description of cases divergent from current evidence on this topic could provide new insights to better understand SARS-CoV-2 vertical transmission.

Characteristics of Living Systematic Review for COVID-19

Purpose

The systematic review aims to analyze and summarize the characteristics of living systematic review (LSR) for coronavirus disease 2019 (COVID-19).

Methods

Six databases including Medline, Excerpta Medica (Embase), Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Database and China Science, and Technology Journal Database (VIP), were searched as the source of basic information and methodology of LSR. Descriptive analytical methods were used to analyze the included COVID-19 LSRs, and the study characteristics of COVID-19 LSRs were further assessed.

Results

Sixty-four COVID-19 LSRs were included. Eighty-nine point one percent of LSRs were published on Science Citation Index (SCI) journals, and 64.1% publication with an impact factor (IF) >5 and 17.2% with an IF >15 among SCI journals. The first unit of the published LSRs for COVID-19 came from 19 countries, with the largest contribution from the UK (17.2%, 11/64). Forty point six percent of LSRs for COVID-19 were related to therapeutics topic which was considered the most concerned perspective for LSRs for COVID-19. Seventy-six point six percent of LSRs focused on the general population, with less attention to children, pregnant women and the elderly. However, the LSR for COVID-19 was reported incomplete on “living” process, including 40.6% of studies without search frequency, 79.7% of studies without screening frequency, 20.3% of studies without update frequency, and 65.6% of studies without the timing or criteria of transitioning LSR out of living mode.

Conclusion

Although researchers in many countries have applied LSRs to COVID-19, most of the LSRs for COVID-19 were incomplete in reporting on the “living” process and less focused on special populations. This could reduce the confidence of health-care providers and policy makers in the results of COVID-19 LSR, thereby hindering the translation of evidence on COVID-19 LSR into clinical practice. It was necessary to explicitly enact preferred reporting items for systematic reviews and meta-analyses (PRISMA) to improve the reporting quality of LSR and support ongoing efforts of therapeutics research for special patients with COVID-19.

Evaluation of transplacental transfer of mRNA vaccine products and functional antibodies during pregnancy and infancy

Studies are needed to evaluate the safety and effectiveness of mRNA SARS-CoV-2 vaccination during pregnancy, and the levels of protection provided to their newborns through placental transfer of antibodies. Here, we evaluate the transplacental transfer of mRNA vaccine products and functional anti-SARS-CoV-2 antibodies during pregnancy and early infancy in a cohort of 20 individuals vaccinated during late pregnancy. We find no evidence of mRNA vaccine products in maternal blood, placenta tissue, or cord blood at delivery. However, we find time-dependent efficient transfer of IgG and neutralizing antibodies to the neonate that persists during early infancy. Additionally, using phage immunoprecipitation sequencing, we find a vaccine-specific signature of SARS-CoV-2 Spike protein epitope binding that is transplacentally transferred during pregnancy. Timing of vaccination during pregnancy is critical to ensure transplacental transfer of protective antibodies during early infancy.

The impact of withholding nitrous oxide in labour during the COVID-19 pandemic on maternal and neonatal outcomes

Nitrous oxide is commonly used in Australia for labour analgesia. Its use in labour is potentially associated with aerosol generation. During the first wave of the COVID-19 pandemic of 2020, nitrous oxide was suspended on many birthing units to reduce the risk of transmission. We aimed to determine the impact of withholding nitrous oxide for labour analgesia, during the COVID-19 pandemic, on epidural rates, opioid analgesia use, and maternal and neonatal outcomes. Withholding nitrous oxide for labour analgesia did not alter epidural rates but did significantly increase opioid analgesia use. Caesarean section rates, post-partum blood loss and neonatal APGAR scores did not change.

Obstetric-Neonatal Care during Birth and Postpartum in Symptomatic and Asymptomatic Women Infected with SARS-CoV-2: A Retrospective Multicenter Study

This study analyses the obstetric−neonatal outcomes of women in labour with symptomatic and asymptomatic COVID-19. A retrospective, multicenter, observational study was carried out between 1 March 2020 and 28 February 2021 in eight public hospitals in the Valencian community (Spain). The chi-squared test compared the obstetric−neonatal outcomes and general care for symptomatic and asymptomatic women. In total, 11,883 births were assisted in participating centers, with 10.9 per 1000 maternities (n = 130) infected with SARS-CoV-2. The 20.8% were symptomatic and had more complications both upon admission (p = 0.042) and during puerperium (p = 0.042), as well as transfer to the intensive care unit (ICU). The percentage of admission to the Neonatal Intensive Care Unit (NICU) was greater among offspring of symptomatic women compared to infants born of asymptomatic women (p < 0.001). Compared with asymptomatic women, those with symptoms underwent less labour companionship (p = 0.028), less early skin-to-skin contact (p = 0.029) and greater mother−infant separation (p = 0.005). The overall maternal mortality rate was 0.8%. No vertical transmission was recorded. In conclusion, symptomatic infected women are at increased risk of lack of labour companionship, mother−infant separation, and admission to the ICU, as well as to have preterm births and for NICU admissions.

Guidelines for the prevention and management of children and adolescents with COVID-19

Children are the future of the world, but their health and future are facing great uncertainty because of the coronavirus disease 2019 (COVID-19) pandemic. In order to improve the management of children with COVID-19, an international, multidisciplinary panel of experts developed a rapid advice guideline at the beginning of the outbreak of COVID-19 in 2020. After publishing the first version of the rapid advice guideline, the panel has updated the guideline by including additional stakeholders in the panel and a comprehensive search of the latest evidence. All recommendations were supported by systematic reviews and graded using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Expert judgment was used to develop good practice statements supplementary to the graded evidence-based recommendations. The updated guideline comprises nine recommendations and one good practice statement. It focuses on the key recommendations pertinent to the following issues: identification of prognostic factors for death or pediatric intensive care unit admission; the use of remdesivir, systemic glucocorticoids and antipyretics, intravenous immunoglobulin (IVIG) for multisystem inflammatory syndrome in children, and high-flow oxygen by nasal cannula or non-invasive ventilation for acute hypoxemic respiratory failure; breastfeeding; vaccination; and the management of pediatric mental health.

CONCLUSION

This updated evidence-based guideline intends to provide clinicians, pediatricians, patients and other stakeholders with evidence-based recommendations for the prevention and management of COVID-19 in children and adolescents. Larger studies with longer follow-up to determine the effectiveness and safety of systemic glucocorticoids, IVIG, noninvasive ventilation, and the vaccines for COVID-19 in children and adolescents are encouraged.

WHAT IS KNOWN

• Several clinical practice guidelines for children with COVID-19 have been developed, but only few of them have been recently updated. • We developed an evidence-based guideline at the beginning of the COVID-19 outbreak and have now updated it based on the results of a comprehensive search of the latest evidence.

WHAT IS NEW

• The updated guideline provides key recommendations pertinent to the following issues: identification of prognostic factors for death or pediatric intensive care unit admission; the use of remdesivir, systemic glucocorticoids and antipyretics, intravenous immunoglobulin for multisystem inflammatory syndrome in children, and high-flow oxygen by nasal cannula or non-invasive ventilation for acute hypoxemic respiratory failure; breastfeeding; vaccination; and the management of pediatric mental health.