Viruses represent one of the major environmental agents that cause human illness and disease. However, the ability to diagnose viral infections is limited by detection capability and scope. Here we describe several emerging technologies that provide rapid and/or high-quality viral diagnostic information. Two technologies, novel CRISPR-based diagnostics and a portable DNA sequencing instrument, are uniquely suited to increase the number of viral agents analyzed, even in point of care settings. We also discuss a phage-based method for generating comprehensive viral profiles of previous exposure/infection and a fluid-phase immunoassay that yields highly quantitative viral antibody analyses. Future applications of these approaches will accelerate on-site clinical diagnosis of viral infections and provide insights into the role viruses play in complex diseases.