Viral detection and identification in 20 minutes by rapid single-particle fluorescence in-situ hybridization of viral RNA

The increasing risk from viral outbreaks such as the ongoing COVID-19 pandemic exacerbates the need for rapid, affordable and sensitive methods for virus detection, identification and quantification; however, existing methods for detecting virus particles in biological samples usually depend on multistep protocols that take considerable time to yield a result. Here, we introduce a rapid fluorescence in situ hybridization (FISH) protocol capable of detecting influenza virus, avian infectious bronchitis virus and SARS-CoV-2 specifically and quantitatively in approximately 20 minutes, in both virus cultures and combined throat and nasal swabs without previous purification. This fast and facile workflow is applicable to a wide range of enveloped viruses and can be adapted both as a lab technique and a future diagnostic tool.