Virals are people that have been infected by a Virus and work in the service of them; such as Lieutenant Chauncy, Herr Doktor, and Scuzzy. Virals do not have a choice about working for a virus - once infected they lose the ability to choose and follow orders instead. They must do whatever the virus demands of them.
Megabyte's viral servants were infected in body alone. They could think what they liked about the virus; some hated him, some liked him. But when given orders their body would obey. Almost all of Megabyte's servants were binomes, he had a vast army of them and took every opportunity to infect more. Hack and Slash were robotic servants for Megabyte because they were programed to be his servants, they were not actually infected.
Although Scuzzy worked for Hexadecimal, it is unknown if she infected him or if he simply worked for her willingly. Scuzzy is unendingly loyal to Hex, even when she mistreats him. Although he occasionally disagrees with her actions and insane plots, he is very aware that Hex is strange. It is unknown what Scuzzy's origins are. Hexadecimal had no other servants. For a short time Mike the TV lived with her, but he soon left and returned to running Mainframe's TV network. When she becomes the net's only benign virus, Hex infects Little Enzo's icon as a parting gift, in that it allows his father to reassert his personality from his null state. This infection leaves Little Enzo's will intact, and his icon returns to normal once his father takes what he needs from the infection.
Daemon's viral servants consisted mostly of infected Guardians. Her infection was in mind alone. She did not have control of their bodies, but their mind was turned to be completely loyal to her. When given an order they were all happy to follow it. The leader of her army was Daecon, who willingly deleted himself when she asked him to.
For a complete list of Virals see: Category:Virals