When a person with asthma comes into contact with something that irritates their airways, the muscles around the walls of the airways tighten. The airways become narrower and the lining becomes inflamed and swollen. Sometimes, sticky mucus or phlegm builds up, which can cause further narrowing.
It’s a long-term condition with cough, wheezing and breathlessness.
In the UK, over 5 million people are on treatment for asthma ( 1 in every 12 adults – more commonly women - and 1 in 11 children ).
After childhood asthma, the symptoms may disappear during teenage years, and may return in adulthood ( especially if it was severe in childhood ). Asthma can develop at any age.
The cause of asthma is not fully understood, but you are more likely to have asthma if one or both of your parents has the condition.
Asthma attacks may require hospital treatment and can uncommonly be life-threatening.
Common “ triggers “ include house dust mites ( present throughout the world ), animal fur, pollen, tobacco smoke and air pollution, exercise, cold air and chest infections.
It can be made worse by dust and fumes at work. Occupational asthma is caused by exposure to specific substances at work. While there is no cure, treatment can control the condition, by keeping the air passages open.
It may be prevented by medicines, lifestyle advice and identifying, then avoiding, triggers.
Best estimates for asthma in the Philippines are for a similar number ( 5.5 million ) to the UK. A prevalence has been claimed of 1/8 children aged 13-14 years and about 1/5 in older age groups . Over 3,000 children in Metro Manila aged 13-14 years took part in the International Study of Asthma and Allergies in Children (ISAAC), in which the prevalence was about 1/10. ISAAC has shown that these conditions are increasing, especially in the developing world – more work needs to be done on causes and prevention.
Hay fever and eczema ( skin inflammation ) are related conditions. Millions of people in the UK get hay fever, during the summer or all year round ( 'perennial allergic rhinitis'). I don’t have figures for how common these are in the Philippines.
It’s usually seasonal in the UK ( 'seasonal allergic rhinitis' ). People with hay fever are allergic to pollen ( dust-like particles given off by trees, grasses, weeds and flowers ), or spores ( given off by fungi and moulds ).
Perennial allergic rhinitis is often caused by the same allergens present in everyday life which may cause asthma. These include house-dust mites, furry or feathery animals, certain chemicals or some foods. As soon as allergic people inhale them, or get eye contact, they irritate the linings of nose, throat and eyes. This causes the cold-like symptoms of hay fever, and - if air passages are involved - asthma. There are also effective drugs for hay fever ( antihistamines ).
