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\begin{document}

\title{Blockchain-based Solution for COVID-19 Digital Medical Passports and
Immunity Certificates}



\author[1]{Haya R. Hasan }%
\author[1]{Khaled Salah }%
\author[1]{Raja Jayaraman }%
\author[1]{Junaid Arshad }%
\author[2,2]{Ibrar Yaqoob }%
\author[1]{Mohammed Omar }%
\author[1]{Samer Ellahham }%
\affil[1]{Affiliation not available}%
\affil[2]{Khalifa University of Science and Technology}%


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  \date{June 15, 2024}


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\begin{abstract}
COVID-19 has emerged as a highly contagious disease which has caused a
devastating impact across the world with a very large number of
infections and deaths. Timely and accurate testing is paramount to an
effective response to this pandemic as it helps identify infections and
therefore mitigate (isolate/cure) them. In this paper, we investigate
this challenge and contribute by presenting a blockchain-based solution
that incorporates self-sovereign identity, re-encryption proxies, and
decentralized storage, such as the interplanetary file systems (IPFS).
Our solution implements digital medical passports (DMP) and immunity
certificates for COVID-19 test-takers. We present smart contracts based
on the Ethereum blockchain written and tested successfully to maintain a
digital medical identity for test-takers that help in a prompt trusted
response directly by the relevant medical authorities. We reduce the
response time of the medical facilities, alleviate the spread of false
information by using immutable trusted blockchain, and curb the spread
of the disease through DMP. We present a detailed description of the
system design, development, and evaluation (cost and security analysis)
for the proposed solution. Since our code leverages the use of the
on-chain events, the cost of our design is almost negligible. We have
made our smart contract codes publicly available on Github.%
\end{abstract}%



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