COVID-19 has lately emerged as one of the most difficult pandemics of the twentieth century, with lethal consequences and a high rate of replication. It emphasizes the critical importance of developing effective vaccines to prevent virus infection, early and rapid diagnosis using high sensitivity and selectivity diagnostic kits, and effective antiviral and protective therapeutics to reduce and eliminate viral load and tissue damage-related side effects. As a result, non-toxic antiviral nanoparticles (NPs) are being developed for therapeutic use in the prevention and treatment of COVID-19. Nanoparticles have shown considerable promise in the development of nano vaccines to combat viral diseases. In this paper, we look at the potential of nanoparticles as a medicine or as a platform for drug and vaccine repurposing and development. Meanwhile, sophisticated virus detection methodologies based on NPs will be detailed, with the goal of inspiring scientists to develop cost-effective Nano platforms for prevention, diagnosis, and therapy.