"Symptoms to a common cold are typically a short period of time, lasting a few days to a week, but a sinus infection will have other associated symptoms such as a fever or foul smell, and it tends to linger." Upper respiratory illnesses are more common during the winter season, and many people develop the sniffles. Sometimes those sniffles can progress into a sinus infection. Sinus infections , also called sinusitis, happens when fluid builds up in the air-filled pockets or sinuses, which a...