When I set out to produce a QUEST story on the latest research on the causes of childhood asthma, I didn't expect to discover how little researchers know about this question. They do understand the lung disease's mechanisms: a chronic inflammation of the airways causes an overreaction to allergens like pollen and dust mites, which in turn brings on symptoms like wheezing, coughing and a dangerous tightening of the chest and shortness of breath.
But asthma researchers are still very much working to figure out what, besides changes in the way asthma is diagnosed, might account for the 160 percent rise in the rate of asthma in children younger than 5 that took place between 1980 and 1994. Our QUEST TV story looks at one interesting hypothesis, called the "hygiene hypothesis." The hypothesis proposes that as certain types of bacteria have become less and less present in our lives, we have developed allergic diseases in response.
I also asked researchers if their findings allowed them to make recommendations to parents on what they might be able to do to help reduce the risk of their children developing asthma. Although our two interviewees were careful to caution how little scientists know with certainty at this point, they were willing to venture some advice, which you'll see in our web-only video.