[HTML][HTML] Detection of SARS-CoV-2 in human breastmilk

R Groß, C Conzelmann, JA Müller, S Stenger… - The Lancet, 2020 - thelancet.com
R Groß, C Conzelmann, JA Müller, S Stenger, K Steinhart, F Kirchhoff, J Münch
The Lancet, 2020thelancet.com
It remains unclear whether severe acute respiratory syndrome corona virus 2 (SARSCoV2)
can be shed into breastmilk and transmitted to a child through breastfeeding. Recent
investigations have found no evidence of SARSCoV2 in human breastmilk, but sample sizes
were small. 1–3 We examined milk from two nursing mothers infected with SARSCoV2. Both
mothers were informed about the study and gave informed consent. Ethical approval for this
case study was waived by the Ethics Committee of Ulm University and all samples were …
It remains unclear whether severe acute respiratory syndrome corona virus 2 (SARSCoV2) can be shed into breastmilk and transmitted to a child through breastfeeding. Recent investigations have found no evidence of SARSCoV2 in human breastmilk, but sample sizes were small. 1–3 We examined milk from two nursing mothers infected with SARSCoV2. Both mothers were informed about the study and gave informed consent. Ethical approval for this case study was waived by the Ethics Committee of Ulm University and all samples were anonymised. Clinical data and the timecourse of infection in the two mothers is shown in figure 1. After feeding and nipple disinfection, milk was collected with pumps and stored in sterile containers at 4 C or–20 C until further analysis. We deter mined viral loads using RTqPCR for SARSCoV2 N and ORF1b-nsp14 genes4 in both whole and skimmed milk (obtained after removal of the lipid fraction). Further details of sample storage and processing are provided in the appendix. Following admission and delivery (day 0), four samples from Mother 1 tested negative (figure 2). By contrast, SARSCoV2 RNA was detected in milk from Mother 2 at days 10 (left and right breast), 12, and 13. Samples taken sub sequently were negative (figure 2). Ct values for SARSCoV2 N peaked at 29∙ 8 and 30∙ 4 in whole milk and skimmed milk, respectively, corresponding to 1∙ 32× 10⁵ copies per mL and 9∙ 48× 10⁴ copies per mL (mean of both isolations). Since milk components might affect RNA isolation and quantification, viral RNA recovery rates in milk spiked with serial dilutions of a SARSCoV2 stock were determined. We observed up to 89∙ 2% reduced recovery rate in whole milk and 51∙ 5% in skimmed milk (appendix), suggesting that the actual viral loads in whole milk of Mother 2 could be even higher than detected. We detected SARSCoV2 RNA in milk samples from Mother 2 for 4 consecutive days. Detection of viral RNA in milk from Mother 2 coincided with mild COVID19 symptoms and a SARSCoV2 positive diagnostic test of the newborn (Newborn 2). Mother 2 had been wearing a surgical mask since the onset of symptoms and followed safety precautions when handling or feeding the neonate (including proper hand and breast disinfection, strict washing,
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