Asthma is a chronic condition in which the lungs overreact to triggers like viruses, exercise, cold air, cigarette smoke, and strong fragrances, as well as to allergens like pollen, ragweed, and dust mites. During an attack, the child's airways becomes swollen and inflamed, the cells lining the airways produce excess mucus, and the muscles surrounding them constrict, making breathing difficult. Repeated attacks may cause permanent lung damage; severe, acute ones can be life-threatening. And in babies and young kids, whose airways are very small to begin with, it takes only a little bit of swelling to make it harder for them to breathe.
We don't know exactly why more and more kids (especially those under 4) seem to have asthma these days. (In fact it's the most common childhood chronic condition -- affecting more than 6 million kids, which is twice as many as 30 years ago.) But there are likely several reasons why asthma is on the rise, including:
• Awareness: Now that doctors, parents, and teachers are aware of asthma symptoms, more children are being diagnosed.
• Allergies, which can trigger asthma, are increasing too. This may be related to environmental factors like global warming and poor air quality.
• The hygiene hypothesis: More vaccinations and increased sanitation have left our immune systems less busy attacking germs, leaving them ready to respond to more mild triggers that can lead to allergies and asthma. --Marguerite Lamb
Originally published in American Baby magazine, April 2005.