Metataxonomic analysis of milk samples from SARS-CoV-2- positive and SARS-CoV-2-negative women

Objective: To assess the impact of SARS-CoV-2 viral infection on the metataxonomic profile in breast milk and its evolution during the first month of lactationMethods: Milk samples from 37 women with term pregnancies and confirmed non- severe SARSCoV-2 infection (case group) and from 63 SARS-CoV-2 negative women in identical conditions (control group), provided in the 1st week and in the 5th week post-partum, were analysed in this work. Presence of SARS-CoV-2 RNA was assessed by reverse transcription polymerase chain reaction (RT-PCR) both in cases and controls. After DNA extraction, the V3-V4 hypervariable region of the gene 16S rRNA was amplified and sequenced using the MiSeq system of Illumina. After a quality control, the data were submitted to statistical and bioinformatics analyses.Conclusions: The results showed that, overall, the structure of the bacterial populations were very similar between both groups. This suggests that maternal infection by SARS- CoV-2 does not negatively impact on her human milk microbiota.