Your problem is not likely to have been caused by a virus infection. If the DVD drive is not showing in BIOS Setup, check that the drive's data cable and power cable are properly and firmly connected.
If that makes no difference, it's possible that the DVD drive may have broken and you need to install a new one.
If you are referring to a laptop, I once had that problem on my son's laptop and noticed that the DVD drive was protruding slightly from the laptop edge (not the tray, the entire DVD drive itself). This means it is not properly connected inside. I gave it a firm push and that fixed it. But if it's already pushed in properly, you very probably need a new DVD drive.