Note: I'm not a doctor so consult your physician about any health concerns, especially if traveling to regions where serious threats lurk.
1. Don't fly when you're sick
This sounds so obvious but many of us do fly sick because pricy airline change fees (up to $200) offer little incentive to stay home. If you must fly, be courteous to fellow travelers and carry a family-size supply of tissues (but do not stuff the used ones in the seat-back pocket). Consider a face mask to keep your germs from infecting others. Wait - if you're feeling bad enough to consider a face mask, to heck with the change fee and just stay home.
2. Drink lots of water.
You already know to do this but, remember, you can't get water through security in a container larger than 3.4 ounces so don't bring water from home but an empty bottle is OK (just fill it up after the checkpoint). Or buy a container as big as you like in the shops near your gate.
3. Don't drink alcohol.
4. Wash hands scrupulously.
5. Carry hand sanitizers.
Too bad airplanes don't offer anti-bacterial wipes the way some supermarkets do (I've even seen some at the local library). Bring your own and use as follows:
• Wipe down your tray table. Even if flu-ridden fingers haven't touched it, I've seen too many photos on Passenger Shaming of folks with their feet on these trays!
• Wipe off the armrests. Again, see Passenger Shaming.
• Wipe off the top of the seat in front of you. Not sure how much good it will do on fabric as opposed to hard plastic, but the tops of seats are something people always grab when they stand up and I figure it couldn't hurt.
Goodness knows where it has been.
Opinions expressed in this column do not reflect the views of ABC News.