“Colds spread easily, especially within homes, classrooms and workplaces. A cold is a contagious upper respiratory infection that affects your nose, throat, sinuses and windpipe (trachea). More than 200 different viruses can cause colds. There’s no cure but there are prevention tips for a common cold, but it usually goes away within a week to 10 days. If you don’t feel better in 10 days, see a healthcare provider. Now take Flu season — when cases of the flu go up dramatically — in the Northern Hemisphere (which includes the U.S.) is October through May. The highest number of cases (peak) usually happen between December and February. Every flu season, about 20 to 40 million people in the U.S. catch the flu. Symptoms can be similar. How to tell the difference? Your provider diagnoses the flu by listening to your symptoms and testing a sample of mucus from your nose. They’ll put a long stick with a soft tip (swab) in your nose to test for influenza. Results may take a few minutes or your provider may send the sample to a lab, where you’ll get results in a day or two.”
Cleveland Clinic (https://my.clevelandclinic.org/health/diseases/4335-influenza-flu)