An aggravation can be considered a job injury. A physical impact is not required. Nor is any physical contact with some object. As one judge recently stated:
“The law says an injury is thought of as a rupture or break in the physical structure of the body of a worker.” Judge Stenger quoting Brown v. Lumbermen's Mut. Cas. Co., 49 Ga. App. 99, 174 S.E. 359 (1934).
Certainly, your pre-existing disease that was NOT caused by your job can become aggravated by an incident at work making for a compensable injury.
The most important foundational case on this subject states the following:
It is not necessary, in order for an employee to recover compensation as an injured workman, that he must have been in perfect health or free from disease at the time he received the injury. Every workman brings with him to his employment certain infirmities; his employer takes him as he finds him and assumes the risk of diseased condition aggravated by injury.
This is the case of Griggs v. Lumbermen's Mut. Cas. Co, 61 Ga. App.449 (1939) and Harris v. Peach County Brd. of Commissioners, 296 Ga. App. 225, 674 S.E. 2d 36 (2009).
But, and this is a “big one”, the worker must also prove that the accident arose “out of” the employment AND “in the course of” employment. O.C.G.A. § 34-9-1 (4).
The bottom line here is don't let your supervisor, HR Department ot any other person in a position of authority to tell you that you are barred from filing a workers' compensation claim because of a pre-existing condition.