[antegamisou]

IDK why some smartasses, who probably have not taken Biology in HS, decided to bury your comment but some subtypes of T cells are indeed able to attack virus-infected cells.

https://en.wikipedia.org/wiki/T_cell

[bayesian_horse]

They "attack" them usually in the form of passing a message like "please destroy yourself".

[culi]

I think "attacking" and "relying on for nutrition" isn't the hardest distinction to make. You wouldn't call a Ukrainian tank a "Russovore", would you?