A Privacy-preserving Covid-19 Updatable Test Result and Vaccination Provenance based on Blockchain and Smart contract Justice Odoom Southwest University of Science and Technology Mianyang, China 0000-0003-2765-6977 Richlove Samuel Soglo Southwest University of Science and Technology Mianyang, China 0000-0001-9988-4106 Huang Xiaofang Southwest University of Science and Technology Mianyang, China huangxiaofang@swust.edu.cn Samuel Akwasi Danso Southwest University of Science and Technology Mianyang, China sdanso@gtuc.edu.gh Abstract— It is undisputable fact that Coronavirus pandemic will go into the annals of history as one of the devastating plagues. From the healthcare perspective, a lot of efforts are underway geared towards testing, management and vaccination whereas industry and research communities explore innovative solutions. Quite a number of solutions have emerged zooming in on contact tracing, combating misinformation, data aggregation and analysis as well as test result certification with blockchain technology been the core. Aside the reliance on centralized architectures and use of permissioned/consortium blockchain, conspicuously missing in existing solutions based on blockchain is the work around the immutability feature of the technology given the fact that a person’s test result is not static but dynamic. In this paper, we propose a solution using blockchain and smart contract that allows for state changes to be made by authorized entities. We leverage distributed storage technology using InterPlanetary File System (IPFS) for storage of user encrypted records and subsequent retrieval for verification purposes. We extend our solution by incorporating vaccination status to provide comprehensive source of information and show proof of concept. The full code of our proposed solution is made publicly available on GitHub. Keywords—blockchain, coronavirus, decentralization, privacy, smart contract. I. INTRODUCTION The Coronavirus (Covid-19) pandemic has devasted countries, disrupted a myriad of events and has revolutionized the way and manner individuals, organizations, communities and nations hitherto performed activities. The World Health Organization (WHO) states that over 71 million confirmed cases have been recorded with over a million fatalities [1]. It is therefore not surprising that frantic efforts have been made and currently underway by healthcare professionals, industry and academia alike to curb the pandemic. The quest to manage, test and carry out vaccination has resulted in a plethora of ideas and solutions. Currently, diverse technologies are being explored including Near Field Communication (NFC), Artificial Intelligence (AI) and blockchain [2, 3]. As part of the fight against the pandemic, these technologies are already being applied in contact tracing [4], combating misinformation [5], test kit and Personal Protective Equipment (PPE) supply chain transparency and authentication [2], data aggregation and analysis [3], and test result certification [6, 7] of which blockchain technology is leveraged for anchorage consequently providing a secured, © IEEE 2021. This article is free to access and download, along with rights for full text and data mining, re-use and analysis. decentralized, transparent, and immutable record. Inasmuch as these attributes are laudable and have widely been instrumental in radically transforming such as areas as finance, supply chain management, governance, healthcare [8-11] among others, its transparency and immutability features immediately raise some genuine misgivings specifically privacy and data protection concerns. Moreover, closely related is the fact that an individual’s test result status is not static but dynamic as a person can test negative today and positive at a later date as pointed out by the California blockchain working group [12]. It therefore becomes imperative that a solution that is privacy-focused and allows for record updates is sought so as not to trample on the right to privacy and free travel considering the fact that covid-19 test result certification acts as a provable health record for the purpose of travelling and entry into designated public facilities. The primary contributions of this paper are summarized as follows: • A blockchain-based privacy-preserving covid-19 test result certificate solution that supports update functionality as well as support for vaccination status all accomplished via a smart contract. • Integration of InterPlanetary File System (IPFS) into our solution consequently providing a decentralized storage hub to aid storage of encrypted data and result verification. • Proof of concept is demonstrated by way of development and full implementation of the smart contract with the full code made publicly available on GitHub. • Thorough system analysis by way of cost implications and security analysis are performed. The remainder of this paper is structured as follows. In Section II, a discussion of related work is done whereas Section III vivid details about our proposed solution. In Section IV we perform a robust system evaluation taking into consideration cost and possible security-related issues. Section V concludes the paper and provides an outlook on future work. 2019 International Conference on Mechatronics, Remote Sensing, Information Systems and Industrial Information Technologies (ICMRSISIIT) | 978-1-7281-0486-7/20/$31.00 ©2019 IEEE | DOI: 10.1109/ICMRSISIIT46373.2020.9405872