Describes the scenario as a virus called the melding plague

The Melding Plague is a nanotech virus that attacks anything that has nanotechnology present within it and does not discriminate between human and machine. It attempts to meld the nanomachines and implants that are commonly present in the bodies of humans, with the structure of their body on a cellular level. This results in horrific, uncontrollable modifications to the body of whoever is infected and almost inevitably leads to death.

[link to en.wikipedia.org]