The flu is mostly spread through spit and mucus, so definitely don't kiss him
. Since the odds are high that he's carrying germs on his face, too, it's prob best to avoid smooching him on the cheek as well.
…But You Can Get Busy
That said, if he's feeling up for it, you could have sex
and be okay. Just know that if you're that close you him you're probably breathing his germy air, too, so it's safest to stick with a position like reverse cowgirl where your mouth is facing away from him.
Air Your Dirty Laundry
If you're sharing a bed with your man, wash the sheets, and especially the pillow cases, often. Also, try to sleep with your back to him to prevent him from coughing in your face in the middle of the night.
Drink, Drink, Drink
The faster he gets better, the sooner your next makeout sesh will be. Make sure he's drinking plenty of fluids—and do the same to keep yourself healthy.
Scrubbing your hands frequently with good old soap and water is better for sickness prevention than squirts of hand sanitizer. Just make sure you're washing up right—sing the "Happy Birthday" song in your head while you're sudsing up. When you're finished, it's okay to rinse.
Don't Share Anything
Bottom line: Don't put your mouth where his mouth has been and make sure he's not putting his kisser where it shouldn't be (like swigging directly from the mouthwash bottle that you share).