Biophysical approaches for studying viral entry

Viruses infect all living organisms and have been responsible for major epidemics and pandemics. Their ongoing evolutionary battle with host defenses creates a constant need for improved tools to study viral behavior. Advancing methods to probe viral attachment, fusion, and genome release deepen our understanding of how infections begin and support the development of effective antiviral strategies. In this graphical review, we provide an overview of selected microscopy-based biophysical methods, most relying on extracellular experimental systems, that allow interrogation of the various steps leading to viral entry in both enveloped and non-enveloped viruses.