Was there a viral cause behind the depression one of my early clients struggled with?

This is very much the case and is why you have thought of it now. You have checked on this intuitively and you can see a connection with both his depression and his OCD-like symptoms. This is perturbation by a viral infection going on within the brain itself, so he would benefit greatly from the prayer work you have helped to devise as well as a revisit with the Lightworker Healing Protocol, to have that done on his behalf and then be repeated as a feature of its design on autopilot, so to speak. This would be a blessing, indeed, for him.