Flu viruses are spread mainly by droplets made when people sick with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are nearby. Less often, a person might also get the flu by touching a surface or object that has the flu virus on it and then touching their own mouth, nose, or possibly their eyes.
How long can someone spread the flu virus to others?
People with flu are most contagious in the first 3-4 days after their illness begins. However, some people can infect others before symptoms develop and up to 5-7 days after becoming sick. Some people, especially young children and those with weakened immune systems may be able to infect others for longer than 7