With the development of the Internet, the amount of data generated by the medical industry each year has grown exponentially. The Electronic Health Record (EHR) manages the electronic data generated during the user's treatment process. Typically, an EHR data manager belongs to a medical institution. This traditional centralized data management model has many unreasonable or inconvenient aspects, such as difficulties in data sharing, and it is hard to verify the authenticity and integrity of the data. The decentralized, non-forgeable, data unalterable and traceable features of blockchain are in line with the application requirements of EHR. This paper takes the most common COVID-19 as the application scenario and designs a COVID-19 health system based on blockchain, which has extensive research and application value. Considering that the public and transparent nature of blockchain violates the privacy requirements of some health data, in the system design stage, from the perspective of practical application, the data is divided into public data and private data according to its characteristics. For private data, data encryption methods are adopted to ensure data privacy. The searchable encryption technology is combined with blockchain technology to achieve the retrieval function of encrypted data. Then, the proxy re-encryption technology is used to realize authorized access to data. In the system implementation part, based on the Hyperledger Fabric architecture, some functions of the system design are realized, including data upload, retrieval of the latest data and historical data. According to the environment provided by the development architecture, Go language chaincode (smart contract) is written to implement the relevant system functions.

翻译：随着互联网的发展，医疗行业每年产生的数据量呈指数级增长。电子健康记录（EHR）管理着用户在诊疗过程中产生的电子数据。通常，EHR数据管理者隶属于某个医疗机构。这种传统的中心化数据管理模式存在诸多不合理或不便利之处，例如数据共享困难，且难以验证数据的真实性与完整性。区块链所具有的去中心化、不可伪造、数据不可篡改和可追溯的特性，符合EHR的应用需求。本文以最常见的COVID-19为应用场景，设计了一个基于区块链的COVID-19健康系统，具有广泛的研究和应用价值。考虑到区块链公开透明的特性与部分健康数据的隐私要求相悖，在系统设计阶段，从实际应用角度出发，根据数据特性将其划分为公开数据与私有数据。对于私有数据，采用数据加密方法以确保数据隐私。将可搜索加密技术与区块链技术相结合，实现加密数据的检索功能。随后，利用代理重加密技术实现数据的授权访问。在系统实现部分，基于Hyperledger Fabric架构，实现了系统设计中的部分功能，包括数据上传、最新数据与历史数据的检索。根据开发架构提供的环境，编写Go语言链码（智能合约）以实现相关的系统功能。