Viral nucleic acid load in the milk of lactating mothers with COVID-19 and the prognosis of infants.

The global spread of the novel coronavirus disease 2019, caused by SARS-CoV-2 virus, impacts individuals of all age groups, including lactating women and children. Concerns have been raised regarding the potential transmission of SARS-CoV-2 from mother to child, following the discovery of SARS-CoV-2 RNA in human milk. Therefore, this study aims to investigate whether the Omicron novel coronavirus variants are transmitted through human milk. This study was conducted between March and May 2022 at Children's Medical Center, the First Hospital of Jilin University, Lequn Branch. Fourteen lactating mothers and their breastfed children hospitalized with COVID-19 (Omicron variant) formed mother-child pairs, which constituted the test group. Additional 11 non-breastfed children of the same age hospitalized with COVID-19 (Omicron variant) participated in the study as the control group. Their clinical manifestations were observed, and the milk of lactating mothers with COVID-19 was collected for SARS-CoV-2 RNA detection. Milk samples from each lactating mother were collected consecutively for 2-18 days and subjected to polymerase chain reaction (PCR) testing forSARS-CoV-2 RNA detection. The time span for sample collection ranged from admission to discharged. The symptoms observed in mothers and children infected with the Omicron variant of COVID-19 were primary upper respiratory tract infection, with fever and cough being the main clinical manifestations. In total, 104 breast milk samples were collected from 14 lactating mothers with COVID-19, and all samples were negative for SARS-CoV-2 RNA. This study found no evidence of Omicron variants transmission through breast milk and accepts the safety of breastfeeding for novel coronavirus-positive mothers when contact precautions are taken. Our findings provide additional support for recommendations that lactating women with COVID-19 continue to breastfeed while taking precautions.