The novel coronavirus SARS-CoV-2 has emerged as one of the most compelling and concerning public health challenges of our time. To address the myriad issues generated by this pandemic, an interdisciplinary breadth of research, clinical and public health communities has rapidly engaged to collectively find answers and solutions. One area of active inquiry is understanding the mode(s) of SARS-CoV-2 transmission. Although respiratory droplets are a known mechanism of transmission, other mechanisms are likely. Of particular importance to global health is the possibility of vertical transmission from infected mothers to infants through breastfeeding or consumption of human milk. However, there is limited published literature related to vertical transmission of any human coronaviruses (including SARS-CoV-2) via human milk and/or breastfeeding. Results of the literature search reported here (finalized on 17 April 2020) revealed a single study providing some evidence of vertical transmission of human coronavirus 229E; a single study evaluating presence of SARS-CoV in human milk (it was negative); and no published data on MERS-CoV and human milk. We identified 13 studies reporting human milk tested for SARS-CoV-2; one study (a non-peer-reviewed preprint) detected the virus in one milk sample, and another study detected SARS-CoV-2 specific IgG in milk. Importantly, none of the studies on coronaviruses and human milk report validation of their collection and analytical methods for use in human milk. These reports are evaluated here, and their implications related to the possibility of vertical transmission of coronaviruses (in particular, SARS-CoV-2) during breastfeeding are discussed.

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SARS-CoV-2和母乳：有什么证据？

新型冠状病毒SARS-CoV-2已成为当今时代最引人注目的且关注的公共卫生挑战之一。为了解决由这种大流行引起的无数问题，跨学科的研究，临床和公共卫生界已迅速参与，共同寻找答案和解决方案。主动查询的一个领域是了解SARS-CoV-2传输的模式。尽管呼吸滴是一种已知的传播机制，但其他机制也是可能的。对于全球健康而言，特别重要的是可能通过母乳喂养或食用母乳从受感染的母亲向婴儿垂直传播。但是，关于通过人乳和/或母乳喂养任何人冠状病毒（包括SARS-CoV-2）的垂直传播的文献很少。此处报道的文献检索结果（于2020年4月17日完成）揭示了一项研究，该研究提供了人类冠状病毒229E垂直传播的一些证据。一项评估母乳中SARS冠状病毒的存在的单项研究（阴性）；尚未发布有关MERS-CoV和母乳的数据。我们确定了13项研究报告了检测SARS-CoV-2的人乳；一项研究（未经同行评审的预印本）在一个牛奶样品中检测到病毒，另一项研究在牛奶中检测到SARS-CoV-2特异性IgG。重要的是，关于冠状病毒和人乳的研究均未报道其用于人乳中的收集和分析方法的验证。本文对这些报告进行了评估，并讨论了它们与母乳喂养期间冠状病毒（特别是SARS-CoV-2）垂直传播的可能性有关的含义。