Placental Sampling for Understanding Viral Infections - A Simplified Protocol for the COVID-19 Pandemic

Abstract Objective The coronavirus disease 2019 (COVID-19) is a pandemic viral disease, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The impact of the disease among the obstetric population remains unclear, and the study of the placenta can provide valuable information. Adequate sampling of the placental tissue can help characterize the pathways of viral infections. Methods A protocol of placental sampling is proposed, aiming at guaranteeing representativity of the placenta and describing the adequate conservation of samples and their integrity for future analysis. The protocol is presented in its complete and simplified versions, allowing its implementation in different complexity settings. Results Sampling with the minimum possible interval from childbirth is the key for adequate sampling and storage. This protocol has already been implemented during the Zika virus outbreak. Conclusion A protocol for adequate sampling and storage of placental tissue is fundamental for adequate evaluation of viral infections on the placenta. During the COVID-19 pandemic, implementation of this protocol may help to elucidate critical aspects of the SARS-CoV-2 infection.

## 摘要
### 研究目的
新型冠状病毒肺炎（coronavirus disease 2019, COVID-19）是一种由严重急性呼吸综合征冠状病毒2型（severe acute respiratory syndrome coronavirus 2, SARS-CoV-2）引发的大流行性病毒性疾病。目前该疾病在产科人群中的影响仍不明确，而胎盘相关研究可提供极具价值的参考信息。对胎盘组织开展充分采样，有助于明确病毒感染的相关作用通路。

### 研究方法
本研究提出一套胎盘组织采样方案，旨在确保所采样本具备胎盘组织的代表性，并明确样本的合理保存方式与完整性保障要求，以供后续分析使用。该方案同时提供完整版本与简化版本，可适配不同复杂程度的实验场景开展实施。

### 研究结果
分娩后以尽可能短的间隔实施采样，是保障采样与存储合理性的核心要点。该方案已在寨卡病毒（Zika virus）暴发期间得到实际应用。

### 研究结论
一套规范的胎盘组织采样与存储方案，是对胎盘病毒感染情况进行充分评估的必要基础。在新型冠状病毒肺炎大流行期间，落实该方案将有助于阐明严重急性呼吸综合征冠状病毒2型感染的关键病理特征。