A virus lasts 10 days to 2 weeks. When you have colds for a month or two it's because your immune system is low and you keep catching a new virus and when you get one on top of the other it's awful. So immune boosting is definitely in order however you decide to do that. But Mom & Grandma had it right with rest and lots of fluids. Thankfully, now we have echinachea and other great boosters.