Science

Asthma on the rise in U.S.

A national survey in 2009 shows 8.2 per cent of Americans have asthma. The rate had been holding under eight per cent for the previous four years.

Treatment seems to be improving

Federal health officials in the U.S. say asthma seems to be increasing a little, and that nearly one in 12 Americans now say they have the disease.   

The Centers for Disease Control and Prevention said Wednesday that 8.2 per cent of Americans had asthma in a 2009 national survey of about 40,000 individuals. That's nearly 25 million people with asthma. 

The rate had been holding steady at a little under eight per cent for the previous four years.

CDC officials said better diagnostic efforts could be part of the reason for the increase.

Treatment seems to be improving, with 52 per cent of asthma patients in the 2009 survey saying they suffered an attack in the previous year, down from 60 per cent at the beginning of the decade.