Being contagious with cold and flu is almost the same. For a flu virus for adults, usually we are contagious a day before symptoms show up. Then we continue to be contagious for about a week, seven days. For children though, they can be contagious up to four days prior to symptoms showing up. That's why it seems to spread with them so quickly, but then they also continue for about seven days. With the cold virus though, most of the time, children and adults are contagious for about a day ahead. Then they continue to be contagious ... two to three days, is the maximum spreading time for that, where most infections do occur. After seven days though, you're no longer contagious.
