Vertical transmission and COVID-19: a scoping review

ABSTRACT Objective: Analyze available evidence related to SARS-CoV-2 infection and vertical transmission. Methods: Scoping review, according to the Joanna Briggs Institute and PRISMA-ScR. Searches were conducted in five electronic databases to find publications about coronavirus infection and vertical transmission. Data were extracted, analyzed and synthesized by three independent researchers using a descriptive approach. Results: The search resulted in 76 publications. After selective steps, 15 articles – retrospective descriptive or case studies – were analyzed, all in English. In order to track the infection, specimens were collected from neonates through nasal swabs and C-reactive protein from breast milk, cord blood, amniotic fluid, placenta and vaginal secretion was analyzed. A small percentage of neonates tested positive for COVID-19, but these cases were not attributed to vertical transmission. Conclusion: Vertical transmission could not be demonstrated. Research protocol registered with the Open Science Framework (https://osf.io/fawmv).

摘要
研究目的：分析与严重急性呼吸综合征冠状病毒2（SARS-CoV-2）感染及垂直传播相关的现有研究证据。
研究方法：本研究为范围综述（scoping review），严格遵循乔安娜·布里格斯研究所（Joanna Briggs Institute）及范围综述系统评价首选报告条目（PRISMA-ScR）的规范开展。研究团队在五个电子数据库中开展文献检索，以获取与冠状病毒感染及垂直传播相关的研究成果。由三名独立研究者采用描述性研究方法，对提取的数据进行分析与综合整理。
研究结果：本次检索共获取76篇相关文献，经筛选流程后纳入15篇均以英文发表的回顾性描述性研究或案例研究进行分析。为追踪感染情况，研究人员通过鼻拭子采集新生儿标本，并对母乳、脐带血、羊水、胎盘及阴道分泌物中的C反应蛋白（C-reactive protein）进行检测分析。仅极少数新生儿的新冠病毒检测结果呈阳性，但此类病例均未被归因于垂直传播。
研究结论：本研究未证实垂直传播的存在。本研究方案已在开放科学框架（Open Science Framework，https://osf.io/fawmv）完成注册。