Finding of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) within Placental Tissue 11 Weeks after Maternal Infection.

Trophoblast destruction may act as a potential mechanism to allow the virus to penetrate the chorionic villi and, once it has reached the fetal vessels, to become widespread in the fetal circulation, persisting in fetal vessels and macrophages, as shown (Figure, D). Besides confirming the pathogenesis of damage previously hypothesized, our findings add new relevant information about how long SARS-CoV-2 can survive in human placentas. Chronic histiocytic intervillositis with trophoblast necrosis are risk factors associated with placental infection from coronavirus disease 2019 (COVID19) and intrauterine maternal-fetal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission in liveborn and stillborn infants [published online December 31, 2020]. The authors have no relevant financial interest in the products or companies described in this article. doi: 10.5858/arpa.2021-0076-LE In Reply.-I was very pleased to read the Letter to the Editor by Toto et al in response to our recent article.1 Their description of an 11-week interval between the initial confirmed maternal coronavirus disease 2019 (COVID-19) infection and delivery in which the placenta was found to have immunohistochemical evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein staining is interesting. The placenta has multiple innate immune mechanisms to protect the fetus from infection: these include production of antiviral molecules that can inhibit viral infections;pattern recognition receptors including Toll-like receptors and RIG-I-like receptors that induce antimicrobial signaling pathways;production of type III interferons (IFN-ks) and C19MC microRNAs that restrict viral infections;active transport of antibodies to the fetus through expression of IgG (immunoglobulin G) receptors neonatal FcRn and FcyRIII that are present on the syncytiotrophoblast surface;and physical structure of the syncytiotrophoblastic barrier. Chronic histiocytic intervillositis with trophoblast necrosis are risk factors associated with placental infection from coronavirus disease 2019 (COVID19) and intrauterine maternal-fetal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission in liveborn and stillborn infants [published online December 31, 2020].