I do suspect a virus triggering dry eye, especially in those having low vitamin D. The body may even develop antibodies for the virus, bringing it under control

I do suspect a virus triggering dry eye, especially in those having low vitamin D. The body may even develop antibodies for the virus, bringing it under control, but the dry eye then persists. I feel this is not studied. EBV and CMV are on the top of my suspicion list. One should probably get tested for them, also for the herpes viruses. Some doctors are idiots and don't test for the correct types of antibodies, so doing it oneself after some research is probably more reliable.