For How Long Is Someone Contagious With Swine Flu?

May 27, 2009 -- Question: For how long is someone contagious with swine flu?

Answer: It's not clear exactly how long the contagious period is for swine flu. However, researchers believe that it's similar to seasonal flu in that it lasts for one day before symptoms appear, and then seven days while the individual has symptoms. And this is not exactly clear whether it's the same for individuals of different ages. For example, it may be a longer period for children.