The global prevalence of asthma, already the world's largest respiratory killer, has increased steadily over the past 20 years due mostly to urban development, particularly in the region.

"This problem is set to worsen as Asian populations become more urbanised, unless measures are taken now to improve treatment," the Asia Asthma Development Board (AADB) said at the World Asthma Meeting held here this week.

Experts at the conference, attended by hundreds of scientists and doctors, warned that sufferers in Asia are particularly at risk because doctors are failing to address the chronic condition.

"Asthma is becoming more of a concern in Asia ... and there is a growing problem with asthma related to people living in cities," said Richard Beasley of the Wellington School of Medicine, who co-authored a global strategy for asthma management and prevention.

Urgent and immediate attention is needed in the region to close the widening treatment gap for the growing number of Asian asthmatics, he said.

While several theories about the cause of asthma are in circulation, "undoubtedly one of the factors could be the use of motor vehicles and their emissions," said Eric Bateman, a professor at the University of Cape Town's Lung Institute.

Control of the condition hinges on preventative treatment regimes such as inhaled cortico-steroids, but Asian doctors are often unaware of new medical treatments and control procedures or are reluctant to use them.

The AADB said that poor treatment standards in the region "are leading to some of the highest mortality rates in the world; figures from China suggest that 36.7 of every 100,000 asthma patients will die."

By comparison, in the United States' the death rate is 5.2 per 100,000 and in Canada 1.6.

Singapore, with 16.1 deaths per 100,000, is also an area of concern in Asia and highlights the belief that urban areas are home to abnormally high numbers of asthma sufferers.

Medical professor Nan-Shan Zhong, who heads the China Asthma Society, cast doubt on the AADB figure for China, but conceded asthma had reached alarming levels in the world's largest nation.

In the southern city of Guangzhou, asthma prevalence in 13-14 year-olds jumped from 2.7 percent in 1994 to 3.8 percent in 2002, he said.

"In towns and rural areas, very few doctors know how to treat asthma patients," he added.

AADB chairman Christopher Lai from Hong Kong said the condition can be brought to heel.

"It can be completely controlled ... but patients and doctors have a low expectation of asthma control and many of them do not realize asthma can be treated to such an extent," he told AFP.

The recent emergence of Severe Acute Respiratory Syndrome (SARS), which killed nearly 800 people and infected 8,000 last year, and the ongoing bird flu epidemic has dominated health experts' attention, he said.

Asthma, a chronic condition of the lungs in which airways become inflamed and swollen, is second to cancer as the major cause of adult death and disability worldwide, with 180,000 preventable deaths per year, according to the AADB.

TERRA.WIRE