Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) universal screening in gravids during labor and delivery

Should pregnant women be screened for SARS-CoV-2 infection? A prospective multicenter cohort study

OBJECTIVE

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), ranges from asymptomatic to severe infection. We aimed to compare the prevalence of COVID-19 in asymptomatic pregnant versus nonpregnant women in order to establish recommendations for a COVID-19 screening strategy.

METHODS

A prospective multicenter cohort study was conducted. Asymptomatic pregnant or nonpregnant women after March 2020 (the time when COVID-19 was first detected in north Israel) were tested for SARS-CoV-2 using nasopharyngeal reverse transcription polymerase chain reaction test, anti-nucleocapsid IgG, and anti-spike IgG. Diagnosis was made if at least one test result was positive. Pregnant women were tested between 34 and 42 weeks, mostly at birth.

RESULTS

Among the 297 participating women, 152 were pregnant and 145 were nonpregnant. The prevalence of asymptomatic COVID-19 was similar between the groups (4 [2.6%] and 8 [5.5%], respectively; P = 0.2). All women with COVID-19 delivered healthy appropriate-for-gestational-age babies without malformations, at term.

CONCLUSIONS

The rate of asymptomatic COVID-19 in pregnant women is low and comparable to the rate among nonpregnant women. Pregnancy outcomes are favorable. Future screening programs should consider that one of 25 screened asymptomatic women will be positive.

Chest imaging in pregnant patients with COVID-19: Recommendations, justification, and optimization

Evaluation of COVID-19 related complication is challenging in pregnancy, due to concerns about ionizing radiation risk to mother and the fetus. Although there are instances when diagnostic imaging is clinically warranted for COVID-19 evaluation despite the minimal risks of radiation exposure, often there are concerns raised by the patients and sometimes by the attending physicians. This article reviews the current recommendations on indications of chest imaging in pregnant patients with COVID-19, the dose optimization strategies, and the risks related to imaging exposure during pregnancy. In clinical practice, these imaging strategies are key in addressing the complex obstetrical complications associated with COVID-19 pneumonia.

Universal Testing Policy for COVID-19 in Pregnancy: A Systematic Review

Background

The coronavirus disease (COVID-19) has spread at an accelerated rate. WHO reported that in the general population, the majority are either asymptomatic or mildly infected. In view of the high risk of SARS-CoV-2 transmission from a pregnant woman to her newborn, healthcare workers and other patients, it is a raised concern whether universal testing should be implemented in this targeted population. The current guidelines have not recommended a universal testing policy. In certain European countries, however, the policy was implemented by some hospitals in regions with high prevalence of COVID-19 infection.

Aim(s)

To assess the justification for universal screening of pregnant women for COVID-19 prior to admission in labor through systematic review of antenatal prevalence of asymptomatic infection, hence risk of inadvertent spread of infection.

Materials and Methods

Three databases confined to PubMed, Ovid and Science Direct were used to search for articles from November 2019 onwards published in the English language. The search was conducted using the keywords “COVID-19” or “coronavirus” or “SARS-CoV-2” and “pregnancy” or “pregnant” or “obstetric” or “labor” and “universal” or “testing” or “prevalence”. The review was registered with PROSPERO.

Results

The search result retrieved 34 studies, with the majority consisting of retrospective cohort studies, while other studies such as prospective cohort study, research letters and a case series were also identified. A total of 19,958 pregnant women were universally tested until the date of report. Overall, the prevalence of universal testing among pregnant women presenting to labor and delivery units are higher in Western regions. From the total number of pregnant women 5.3% tested positive and among these, the majority (75.5%) did not manifest any symptoms at the time of testing.

Conclusion

In areas with high prevalence of COVID-19 infection, the implementation of a universal testing policy among pregnant women presenting to labor and admission units may be cost effective in helping to curb disease transmission.

Systematic Trial Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020184248, PROSPERO: CRD42020184248.

Asymptomatic SARS-CoV-2 infection: A systematic review and meta-analysis

Quantification of asymptomatic infections is fundamental for effective public health responses to the COVID-19 pandemic. Discrepancies regarding the extent of asymptomaticity have arisen from inconsistent terminology as well as conflation of index and secondary cases which biases toward lower asymptomaticity. We searched PubMed, Embase, Web of Science, and World Health Organization Global Research Database on COVID-19 between January 1, 2020 and April 2, 2021 to identify studies that reported silent infections at the time of testing, whether presymptomatic or asymptomatic. Index cases were removed to minimize representational bias that would result in overestimation of symptomaticity. By analyzing over 350 studies, we estimate that the percentage of infections that never developed clinical symptoms, and thus were truly asymptomatic, was 35.1% (95% CI: 30.7 to 39.9%). At the time of testing, 42.8% (95% prediction interval: 5.2 to 91.1%) of cases exhibited no symptoms, a group comprising both asymptomatic and presymptomatic infections. Asymptomaticity was significantly lower among the elderly, at 19.7% (95% CI: 12.7 to 29.4%) compared with children at 46.7% (95% CI: 32.0 to 62.0%). We also found that cases with comorbidities had significantly lower asymptomaticity compared to cases with no underlying medical conditions. Without proactive policies to detect asymptomatic infections, such as rapid contact tracing, prolonged efforts for pandemic control may be needed even in the presence of vaccination.

A Comprehensive Analysis of Maternal and Newborn Disease and Related Control for COVID-19

The maternal-fetal/newborn unit is established at risk for COVID-19 infection. This narrative review summarizes the contemporary and cumulative publications which detail maternal infection, antenatal and newborn infections, and maternal/fetal/newborn management and prevention. There is a wide spectrum of maternal disease, but the potential for severe disease albeit in a minority is confirmed. COVID-19 carries risk for preterm delivery. Pregnant females can suffer multisystem disease, and co-morbidities play a significant role in risk. Congenital infection has been supported by several anecdotal reports, but strong confirmatory data are few. No typical congenital dysmorphisms are evident. Nevertheless, placental vascular compromise must be considered a risk for the fetus during advanced maternal infections. Clinical manifestations of newborn infection have been mild to moderate and relatively uncommon. Proven antiviral therapy is of yet lacking. The mode of delivery is a medical decision that must include patient risk assessment and patient directives. Both presymptomatic and asymptomatic mothers and offspring can complicate infection control management with the potential for spread to others in several regards. In the interim, infections of the maternal-fetal-newborn unit must be taken seriously both for the disease so caused and the potential for further dissemination of disease.

Screening of severe acute respiratory syndrome coronavirus-2 infection during labor and delivery using polymerase chain reaction and immunoglobulin testing

Aims

To assess severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during labor and delivery with polymerase chain reaction (PCR) and using immunoglobulin G and M testing to correlate with maternal and perinatal outcomes.

Main methods

Pregnant women admitted for labor and delivery at two Spanish hospitals were screened for SARS-CoV-2 infection by PCR test and by detection of serum immunoglobulins G and M. Maternal and perinatal outcomes were compared in women with laboratory evidence of SARS-CoV-2 infection with those with negative tests.

Key findings

Between March 31st and September 30th, 2020, 1211 pregnant women were screened for SARS-CoV-2 infection. The prevalence of laboratory evidence of SARS-CoV-2 infections was 5.4% (n = 65), corresponding to (i) 22 ongoing infections at admission, including two with mild clinical symptoms and 20 asymptomatic women; (ii) 43 cases of previous SARS-CoV-2 exposure; (iii) and 1146 women who were negative for both SARS-CoV-2 PCR and serological test. None of the screened mothers required hospital admission for coronavirus disease before or after delivery, nor were any of the newborns admitted to the intensive care unit. All newborns from mothers with positive PCR on admission were PCR negative. There were no significant differences in maternal or perinatal outcomes among the three studied groups.

Significance

Ongoing or previous SARS-CoV-2 infection with asymptomatic or mild clinical symptoms detected during screening in pregnant women at labor and delivery do not have a higher rate of adverse maternal or perinatal outcomes.

Immunological Changes in Pregnancy and Its Relation to COVID-19 Infection

This chapter describes the immunological adaptation to pregnancy. A special focus is drawn on the susceptibility to viral infections, especially COVID-19. Older literature refers to the pregnancy as an immunosuppressive state, while recent studies show an immunomodulation to adapt to the growing semiallograftic fetus. Despite this, pregnant women are not susceptible to all viral infections. Regarding influenza, pregnant women are not more susceptible to the infection, but more severe maternal courses. To prevent this, influenza vaccination is recommended for pregnant women. Based on the available evidence, pregnant patients are also not more susceptible to infection with regard to COVID-19 infection. Yet, more severe courses are described throughout gestation with the onset of obstetrical complications.