How Flu Spreads
A person who has the flu is contagious. That means they can spread viruses.
Adults can be contagious from a day before feeling sick to up to 7 days
after getting sick. Children can be contagious for longer than 7 days.
Influenza spreads quickly and easily. The first person who has it coughs or sneezes. This releases viruses into the air and other people inhale them. When these viruses enter the nose, throat or lungs, they begin to multiply and cause disease. The viruses can also be spread when a person touches a surface with flu viruses on it (for example, a door handle) and then touches his or her nose or mouth.
