I'm Sarah Long. And this is Bob Doughty with the VOA Special English program SCIENCE IN THE NEWS.
Today, we tell about the disease asthma. It affects as many as one hundred fifty million people around the world.
Asthma is a serious lung disease that causes breathing problems. These problems, called asthma attacks, can kill. Asthma can affect people of all age groups but often begins in childhood. It can be controlled but not cured. Sufferers must deal with the disease every day.
Stavros Kontzias (cun-ZEE-ahs) is an eight-year-old boy living near Washington, D-C. He developed asthma when he was about two years old. His parents, Susie and Zack, say the breathing problems would appear whenever Stavros got sick with a cold or lung infection.
His father remembers those experiences as very frightening. He says Stavros coughed a lot. The boy struggled to breathe. His breathing became very loud and had a strange sound. That kind of breathing is called wheezing. Mr. Kontzias says his son never turned blue from a lack of oxygen. But, he says it was apparent that little air was getting into Stavros's lungs.
The Kontziases made several emergency visits to the hospital when Stavros became sick. Once there, doctors gave the boy drugs called steroids. Mr. Kontzias says the steroids worked very fast to open his son's air passages. But, he says he began to worry about long-term effects of high amounts of steroids as the trips to the hospital increased.
So, his parents took Stavros to a pulmonary pediatric specialist. That is a doctor who is an expert in diseases that affect children's lungs. The doctor listened to the boy's lungs. He also used measuring devices to test the child's airflow limitations. The combination of the test results and Stavros's medical history showed he had asthma.
Stavros began a treatment of four medicines a day to control his asthma. The Kontziases also took other steps to control their son's asthma. They removed all floor coverings in Stavros's room and most of the house. They also changed the activities he was involved in.
For example, the boy stopped playing European football, or soccer. The continuous running required to play the sport severely decreased his breathing ability. So Stavros began to play baseball instead. It gave him more time to rest and requires much less running.
Stavros and his family saw improvement in the boy's health over the next several years. His trips to the hospital emergency room grew increasingly rare. Also, Stavros's doctor slowly reduced the amount of medicine the boy took.
Recently, Zack and Suzie Kontzias reported good news. They say their son has not taken any steroid medicine since last summer. And they say he has not had an asthma attack. His parents also noted that those months included a season of American football, Stavros's latest interest. The Kontziases now hope the asthma may completely disappear as their son gets older.
Doctors do not know the cause of asthma. Yet they have identified most of its triggers. For example, the common cold can cause an asthma attack in a person who has the disease. There also are several air pollutants that can lead to an asthma attack. Pollen is one such pollutant. Pollen is a fine dust that comes from plants that produce seeds. However, almost any kind of dust can cause an asthma attack if enough of it is in the air. This includes common dust found in houses.
Air pollution from burning fuel also can cause an asthma attack. Tobacco smoke can do the same. Some kinds of animal hair are a trigger for asthma. And, even some insects in the home can lead to asthma attacks.
Several things happen in the lungs when an asthma sufferer has an attack. Cells in the air passages begin to produce too much of a thick, sticky substance called mucous. The mucous creates blocked areas in the air passages. The tissue that lines the air passages begins to expand at the same time. And, the muscles in the passages tighten.
All these changes cause the air passages to narrow. This reduces the amount of air that can flow in and out of the lungs. The sufferer can not get a good, deep, breath of air. The narrowed airways also cause coughing and a tight feeling in the chest.
Health experts say asthma cases are increasing around the world. The World Health Organization says asthma rates worldwide are increasing on average by fifty percent every ten years. W.H.O. officials say asthma cases in western Europe have increased by two times in ten years. They say the number of asthma sufferers has increased in the United States by about sixty percent in the past twenty years.
American experts give an even higher number. The American Academy of Allergy, Asthma and Immunology says the rise was seventy-five percent in about the same time period. It also says more than twenty million Americans report having the disease.
The number of deaths from asthma also has risen in the United States. The W.H.O. says about five thousand Americans die from asthma attacks each year. In the early nineteen-eighties, the yearly death rate from asthma in the United States was about half that.
The World Health Organization says asthma is not just a problem in industrial countries. It says the disease affects people in developing nations, too. However, the incidence of the disease differs greatly from area to area. W.H.O. officials say as many as twenty million people suffer from the disease in India.
The officials say an estimated fifteen percent of Indian children suffer from the disease. They also say almost twenty percent of children in Kenya show signs of asthma. Brazil, Costa Rica, Panama, Peru and Uruguay also have a high rate of childhood asthma. The W.H.O. says as many as thirty percent of children in those countries show signs of asthma.
Asthma kills about one hundred eighty thousand people a year. The W.H.O. says the disease also has huge economic costs. The costs linked to asthma are believed to be higher than those of tuberculosis and AIDS combined. The W.H.O. says the United States spends six thousand million dollars a year on health care and other economic costs of asthma. It says Britain spends almost a third of that on health care for the disease and lost productivity of workers.The World Health Organization says greater international action is needed to deal with asthma. It says asthma sufferers, healthcare providers and the general public must learn more about the disease and the problems linked to it. The W.H.O. says a worldwide system should be put into effect to observe and record asthma rates around the world. And, it says more research is needed to find the cause of asthma and develop new ways to treat it.
Medical experts have suspected for some time that there was a genetic link to asthma. A child has a greater chance of developing asthma if his or her parent is asthmatic. British and American scientists say they may have found a gene involved in the disease.
Three groups of researchers took part in the study. One group worked for Genome Therapeutics, a drug company in Waltham, Massachusetts. The other scientists were from the drug maker Schering-Plough and the University of Southampton in Britain.
The gene is called ADAM thirty-three. The scientists identified it through genetic testing of more than four-hundred families in the United States and Britain whose members have the disease. The scientists say the gene alone does not cause asthma. But, they say its presence appears to increase a person's chances of developing the disease.
They say the gene may be involved in the main condition of asthma — the narrowing of airway passages. However, the scientists say it is too early to say what percentage of asthma sufferers may have an abnormal gene.
Scientists say the finding could lead to new research about the causes of asthma and new drugs to treat the disease. It could also lead to methods to identify people most at risk for asthma and early treatment to help prevent the development of the disease.
This SCIENCE IN THE NEWS program was written by Caty Weaver. It was produced by Jill Moss. Dwayne Collins was our engineer. I'm Bob Doughty. And this is Sarah Long. Join us again next week for more news about science in Special English on the Voice of America.