Asthma rates are rising around the world yet no one knows why, according to an expert on the disease in Bermuda this week.

The disease affects 12 percent of Bermuda's population – 9,000 people and last year King Edward VII Memorial Hospital's emergency department handled 1,500 visits due to asthma, half of which were children.

Speaking on World Asthma Awareness Day yesterday Professor Martyn Partridge, Professor of Respiratory Medicine at Imperial College London, said asthma was rising dramatically everywhere to almost epidemic levels.

He said he was glad experts were big enough to admit they were stumped at the cause of the asthma rise, rather than rush into a faulty solution which did nothing but waste time.

"What we know is people inherit a tendency for asthma and something in the environment switches it on."

Dr. Partridge said the problem was much worse than 30 years ago.

"But we won't have changed our genetic constitution in that 30 years. There is something in modern lifestyle."

And he said there was nothing anyone could do to prevent asthma developing in their children.

Asthma rates were higher in the richer countries but sufferers with the most severe cases were in poorer countries, said Dr. Partridge.

Diet, maternal smoking, pollution and indoor environments such as cooking methods and furnishings were all being looked at.

"It's very likely there are several factors working together."

There's a suggestion that breast feeding might reduce the likelihood of children developing non-allergic asthma, although most sufferers had something which set off a particular allergy such as house dust, pollen or cockroaches.

Dr. Partridge added: "We can't prevent asthma or cure it, but we can jolly well control it."

Experts say it's important those with the disease contained it and managed it so they didn't need to rush into emergency.

Bermuda Hospital's Board Asthma Nurse Educator Debbie Barboza urged asthma sufferers who had symptoms twice a week, such as coughing or a tight chest, to get in touch with her on 239-1652.