 Further, endosomes transport the virus through the cell and ensure that no trace of the virus is left on the surface, which could be a substrate for immune recognition.A third and more specific example, is by simply attaching to the surface of the cell via receptors on the cell, and injecting only its genome into the cell, leaving the rest of the virus on the surface.This is restricted to viruses in which only the gene is required for infection of a cell (most positive-sense, single-stranded RNA viruses because they can be immediately translated) and further restricted to viruses that actually exhibit this behavior.