The year 2020 has witnessed the emergence of coronavirus disease (COVID-19) that has rapidly spread and adversely affected the global economy, health, and human lives. The COVID-19 pandemic has exposed the limitations of existing healthcare systems regarding its inadequacy to timely and efficiently handle public health emergencies. A large portion of today's healthcare systems are centralized and fall short in providing necessary information security and privacy, data immutability, transparency, and traceability features to detect frauds related to COVID-19 vaccination certification, anti-body testing, and medical supplies. Blockchain technology can assist to combat the COVID-19 pandemic by assuring safe and reliable medical supplies, accurate identification of virus hot spots, and establishing data provenance to verify the genuine personal protective equipment that is decentralized, trustworthy, traceable, and transparent. In this paper, we discuss the potential blockchain applications for the COVID-19 pandemic. We present the high-level design of three blockchain-based systems to enable the governments and medical professionals to efficiently handle health emergencies caused by COVID-19. We discuss the important ongoing blockchain-based research projects to demonstrate the adoption of blockchain technology for the COVID-19. Finally, we identify and discuss future research challenges along with their key causes and guidelines.