The flu virus spreads from person to person through respiratory droplets, or when you breathe in germs transmitted in the coughs or sneezes of someone who has the flu. It is also spread when you touch something with the virus on it, and then touch your mouth, nose, or eyes. This is why it’s important to cover your cough, frequently wash your hands, and stay home if you are experiencing any flu symptoms. The typical incubation period for the flu is one to four days, with symptoms lasting anywhere from a few days to over a week. Adults can be contagious anywhere from the day before symptoms begin to 10 days after symptoms first appeared. The flu spreads quickly and easily, often striking a particular community all at once. Students or workers who haven’t received a flu shot generally become sick within two or three weeks of the flu’s arrival in a school or workplace.