Viral exanthems are rashes that form after a viral illness
A viral exanthem is a rash that occurs in the setting of a viral illness. There are many viral illnesses that can result in a rash. Some of the more notable and common viruses include hand-foot-mouth disease (enterovirus), measles (paramyxovirus), chickenpox (varicella-zoster virus) and roseola (herpesvirus 6). A viral infection of any kind in children can cause a rash even if the exact virus is not known.