VDTs (presumably Virtual Disease Transmissions) was a medical condition in the Real World that was speculated to result from an infection of the mind (through hacking or other means) while within the Matrix.
The only surviving record of a patient suspected of having VDTs is Bane, who had self-inflicted wounds on his arms, caused by Smith, who had taken control of his body in the Real World. Bane was the only survivor of the Caduceus, and appeared to be in a coma when he was rescued by the Mjolnir. The Mjolnir's medic Maggie noticed his injured arms, and wondered if it might be as a result of VDTs. She tested him for VDTs, but the results came back negative, instead showing unusual brain activity, including cross-synaptic firing, signs of recent trauma, and fresh fibrotic scarring throughout the cortex, presumably the result of Smith having taken over Bane's mind. When Bane (Smith) woke from the coma, he was questioned by the Mjolnir's Captain Roland, who asked about the cuts on his arms; Bane's reply was strange, making Roland also wonder whether this was as a result of VDTs.
- Maggie: "You see these cuts? I think they're self-inflicted."
- Trinity: "Why?"
- Maggie: "VDTs, maybe. I don't know."
- Roland: "What about the cuts on your arms? Those cuts are more than one day old."
- Bane: "Yeah, definitely. You're right about that, sir. They look like they might be self-inflicted. Why would I do something like that to myself? Unless, of course, I wasn't myself... but... if I'm not me, then who am I?"
- Roland: "Has this man been tested for VDTs?"
- Maggie: "Yes, sir, it was negative. But he is showing a lot of unusual neural activity. Some cross-synaptic firing as well as signs of recent trauma, with fresh fibrotic scarring throughout the cortex."
- The only mentions of VDTs are in The Matrix Revolutions, but it is only mentioned twice, in passing, with no clear explanation of the condition, nor what the abbreviation stands for.
- Delirium Tremens (generally abbreviated to "DTs") is an out-of-universe condition, an alcohol withdrawal symptom, which can cause confusion, shaking and hallucinations. Because of the similarity of abbreviation (and the fact that the symptoms are close enough to be a possible match for what the crew of the Mjolnir thought may have happened to Bane) it is assumed that VDTs stands for "Virtual Delirium Tremens", with the "Virtual" indicating that it was caused by withdrawal from the Matrix, rather than alcohol, though there is no proof of this.
- Despite no official sources that directly state what VDTs stands for, some official translations do support "Virtual Delirium Tremens", such as the German use of "virtuelles Delirium", rather than giving an abbreviation.
- While there's no known way of testing for a hangover or withdrawal other than observation, there are ways to test for viruses and hacks which - combined with the similarity to the term "STD" (Sexually Transmitted Disease) makes the term 'Virtual Disease Transmission" a more plausible explanation, suggesting that Mr Smith's mind hack of Bane would be equivalent to a zero day virus that evaded detection on egress from the Matrix.