In 2019, the pandemic induced by the rapid spread of the severe acute respiratory syndrome coronavirus-2 'SARS-CoV-2', also named coronavirus disease 'COVID-19', has rapidly caused serious health, economic, social, and political issues worldwide. This has been accentuated by asymptomatic carriers, fast viral mutations, incoherent lockdown policies, and limited methods of detection and treatment. Nucleic acid tests for COVID-19 are lengthy and complicated, and the rapid antibody tests produce false-negative diagnoses, particularly in the early stage of infection. Moreover, there are no specific and effective medicines available for treatment. Therefore, rapid diagnostics and therapeutics are urgently required. Here, we argue that nanozymes—enzyme-mimicking nanoparticles—could be used for faster, more sensitive, and accurate detection and treatment of the COVID-19. Indeed, nanozymes have high surface areas allowing easier bioconjugation for detection, and nanozymes possess integrated drug-functionalization for treatment. Moreover, the size, composition, and surface chemistry of nanozymes can be rationally designed for improved theranostic applications.