SARS-CoV-2 infection in infants born from maternal COVID-19 cases during a period when the Omicron variant predominates

In a recent study published in Pediatrics Journal, Researchers find SARS-CoV-2 Omicron Variant of Concern (VOC) predominance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among infants born with SARS-CoV-2 We evaluated the incidence. positive mom.

They also investigated whether the duration of maternal SARS-CoV-2 infection affected neonatal susceptibility.

study: Predominance of omicron variants in infants born to SARS-CoV-2 infected individualsImage Credit: DaAntipina/Shutterstock.com

Background

The constant evolution of SARS-CoV-2 has given rise to several VOCs with varying infectivity, pathogenicity and immune evasion.

Omicrons are highly contagious, but do not cause severe infections among the general population. However, increased neonatal hospitalizations have been reported during the Omicron wave compared to previous VOC waves.

Maternal COVID-19 can transfer antibodies against SARS-CoV-2 across the placenta to the newborn. However, passively acquired humoral protection is rapidly lost within 6 months.

Furthermore, as the COVID-19 vaccine is not licensed for infants younger than 6.0 months of age, evaluation of the humoral immune response to the emerging SARS-CoV-2 VOC is an important tool for policymaking and reducing neonatal burden. Important to support strategy development. COVID19.

About research

In the current study, researchers evaluated COVID-19 incidence in newborns born to mothers infected with COVID-19 before and after the emergence of omicron.

Data on infants under 6 months of age born to SARS-CoV-2-positive mothers in 2020-2021 will be collected from the New Threats to Pregnant Individuals Monitor, regulated by the United States and six jurisdictions. documented by the Infant Network (SET-NET). (United States) Centers for Disease Control and Prevention (CDC).

The team will screen all polymerase chain reaction (PCR) reports (Missouri, Massachusetts, Tennessee, Puerto Rico, and throughout Philadelphia) for newborns meeting eligibility criteria or reporting samples randomly selected from the same population. ), we have included data obtained from jurisdictions that report

The incidence of first laboratory-confirmed COVID-19 in newborns before and after the appearance of omicron was calculated.

March 22, 2020 to December 18, 2021 is the Pre-Omicron Period, and December 19, 2021 to September 9, 2022 is the Omicron Dominant Period. In addition, incidence rate ratio (IRR) values ​​were calculated by comparing the two COVID-19 periods.

Additionally, the team performed a sub-analysis limiting the analysis to neonates born to mothers diagnosed with COVID-19 before December 5, 2021. law.

result

The timing of SARS-CoV-2-positive testing in this study paralleled the national course of the COVID-19 pandemic. In the pre-Omicron wave, 27,403 SARS-CoV-2 infections were documented, and the incidence of SARS-CoV-2-positive infants (born to mothers with COVID-19) under 6 months of age was 100. It was 3.10 per year.

During the Omicron dominance period, the infection rate increased to 15 per 100 years and 14,115 infections were recorded (IRR 5.0).

Restricting the analysis to neonates born to mothers with pre-omicron VOC infections increased the IRR value to 5.8. The proportion of neonates infected within 2.0 weeks after birth and the proportion of mothers infected with SARS-CoV-2 by 2.0 weeks before delivery decreased from 31.0% before Omicron dominance to 0.80% during Omicron dominance. bottom.

Findings indicated that the increase in COVID-19 incidence was not the result of an increase in perinatal SARS-CoV-2 infections.

Conclusion

Overall, the study results showed that COVID-19 in neonates born to SARS-CoV-2-positive mothers was five times greater during Omicron prevalence than during Omicron VOC prevalence.

The rising incidence of COVID-19 reflects the rate recorded for the general public and the increase in neonatal hospitalizations during that period.

In line with previous observations of reduced immunoprotection against omicron VOCs due to pleomicron VOC infection, the IRR was expanded by restricting the analysis to neonates of women who suffered from pleomicron VOC infection during pregnancy.

The findings suggest that SARS-CoV-2 transmission through other means, such as administering COVID-19 vaccine to pregnant and postpartum women, can be prevented to protect infants from COVID-19 and its adverse effects. Indicates that it is important.

Research restrictions

This study has some limitations. This study was limited to expecting women and newborns with PCR-confirmed COVID-19, which may underreport unmedicated asymptomatic SARS-CoV-2 infections .

However, a significant proportion (82%) of newborns were not tested for polymerase chain reaction, undermining the validity of the findings.

Furthermore, although home SARS-CoV-2 testing is approved for children under 2 years of age, its use in neonates has led to under-confirmation of neonatal SARS-CoV-2 infection, especially during the Omicron prevalence. may have resulted in

Furthermore, no genome sequencing was performed to confirm the causative VOCs. Finally, it may be greater during periods of omicron predominance, such as maternal SARS-CoV-2 vaccination status, and various infection control and preventive measures may be less during periods of omicron predominance. There may be time-based unmeasured confounders that influence the association, such as high period.