DETECTION OF SARS-COV-2 IN STOOL BUT NOT NARES OF NEWBORNS OF MOTHERS WITH COVID-19 DURING PREGNANCY

ABSTRACT

Purpose of Study To investigate potential evidence of in utero transmission of SARS-CoV-2 in the stool of newborns born to mothers with COVID-19 infection during pregnancy. Methods Used We investigated stool from 1 day to 2 months of age from 14 newborns born at 25-41 weeks whose mothers had COVID-19 during pregnancy. Newborns were admitted at delivery to the NICU or newborn nursery of our urban academic hospital from July 2020 to May 2021. A comparison group of 30 newborns had similar GAs and were born to mothers without COVID-19 during pregnancy. SARS-CoV-2 RNA was quantified with quantitative PCR using primers against SARS-CoV-2 envelope protein and non-structural protein 14 (NSP-14), spike protein with enzyme-linked immunosorbent assay (ELISA), and inflammatory cytokines interleukin- 6 (IL-6) and interferon-g (IFN-γ) elicited by stool homogenates in mouse bone marrow macrophages. This study was IRB approved with parental consent. Summary of Results Despite negative nasal PCRs from all newborns, viral RNAs and spike protein were detected in the stool of 11 out of 14 newborns as early as the first day of life (range 0-2 months, figure 2A and 2B). Stool RNA and spike protein levels increased over time in 2 and 4 newborns, respectively. Stool homogenates from all newborns elicited elevated inflammatory cytokines, IL-6 and IFN-γ, from mouse macrophages (figure 1). Most newborns were clinically well except for one death from gestational autoimmune liver disease and one with necrotizing enterocolitis. Conclusions These novel findings suggest risk of in utero SARS-CoV-2 transmission to the premature and term fetal intestine during gestation despite negative postnatal nasal PCRs. It is unclear if the presence of viral RNA and protein within the gut microbiome represents active virus in newborns with clinical hospital courses typical of their gestational age in 12 out of 14 cases. However, increasing levels of viral RNA and protein over time suggest replication in some infants, and their gut microbiome induced inflammation in mouse models. The presence of SARS-CoV-2 RNA and spike protein in the intestines of newborns may potentially impact development of the gut microbiome and the immune system and should be further investigated. (Figure Presented).