Transcript for Flu now considered epidemic in US as hospitalizations climb during peak season
The flu reaching epidemic proportions with 49 states now reporting widespread flu activity. That announcement from the CDC the agency also stressing the most vulnerable groups remain people over the age of 65 and children younger than five because their immune systems are not as developed as those of older children everything in sight that kids tax in Idaho this situation so dire cleaning crews are working overtime after an and tie your school district shut down this week. In North Carolina this school also forced to close after 160. Students got sick kids want to share pencils to hear toys when that happens you're gonna a lot of German or action as well so doctors say to keep the virus to wait why shook hands often and carefully. And if you haven't get those flu shot also if you worked. Feeling sick. Don't assume it's too late to fight the bug with anti viral drugs like Tamiflu. You've heard us in the past say they only work in the first 48 hours. New data out of the CDC suggests that is not true there is particularly as survival benefit in higher risk patients if given after that two day window. So treatment should not be withheld just because you're at 49 out. CDC officials say we are now probably at the peak of the flu season but the season could last for another thirteen weeks he'll remember officials say keep washing your hands. And get that flu shocked. With the Perry ABC news New York.
This transcript has been automatically generated and may not be 100% accurate.