No alcohol (unless you're using it to install a Zagg cover), no perfume. It won't damage it, per se, but it will diminish the ability of it to fight off fingerprints and smudges for the first leg of its life.
Remember, you have far more germs than your iDevice. Making sure to wash your hands before you eat, after you sneeze, after going to the restroom, etc. is a better protection than a sterile wipe on your device could ever be.
From
this article, I like the final paragraph. The most pertinent sentences (only using this small snippet for copyright reasons) are
Linked article said:
Infection is certainly a concern, but since we aren’t even taking this as seriously as the NHS in the UK, we still all walk around with petri-dishes we call white-coats, long sleeve shirts, ties, etc. A sealed non-porous surface such as glass or the aluminum case are pretty easily cleaned.
My advice, don't worry. Keep your normal hygienic routine and when you're sick make sure to wash your hands every time you touch near a mucus membrane (eyes, nose, mouth, privy bits, etc.).