Possible Clues:

• Winter ailment
• Ordinary bitter makes one feel unwell
• Winter cause of sniffles and sneezes
• Public land is frozen and there's no remedy, so give it a rest
• Winter woe, for many
• Public land by college is ancient and has an infectious aspect for those picking it up
• Usual commuter's first getting on — there's no cure for it!
• A vulgar ailment