((NOT TALKING FROM EXPERIENCE ON THE NEXT PARAGRAPH - ONLY SPECULATIONS))
alcohol is a bad idea for when you're having anything stronger than mild cold/infection because it acts on your blood system and heart - which are already working on emergency regime. you need all the blood you can get and dont want to load your liver with additional load.
as for the rest, onions and garlic are very strong natural antiviral medicines - as a matter of fact if you have a flu going in a house you can put garlic to a few corners and that'll make things harder on the bug. onions help sustain current illnesses and helps your immune system.
but the best cure is rest
