Germs and Dust May Protect Against Allergies and Asthma

Coming from a study carried out in Europe comes evidence that childrens immune systems work better if they are exposed to germs, dust and dirt from a young age. The studies were published in the September 19, 2002 publication of the New England Journal of Medicine, (NEJM), and in the August 28, 2002 publication of the Journal of the American Medical Association, (JAMA).

The article in the NEJM begins by stating, "It is understood that youngsters of elementary-school age who reside on a farm are less likely to have asthma than their counterparts from nonfarming households." The article in JAMA states, "Exposure to two or more dogs or cats in the first year of life may reduce subsequent risk of allergic sensitization to multiple allergens during childhood." What both these articles say is that it's a needed element of development for kids to be come across certain levels of germs and other irritants to ensure that their immune systems develop properly and provide adequate protection later in life. In the study, children from parts of Austria, Germany, and Switzerland where there were both farming and non-farming households were studied. The investigators related the amount of exposure to endotoxin (such as dust and germs), dependant on sampling dust from the mattresses where the children slept, to the prevalence of asthma and other associated conditions. The higher the endotoxin exposure, the less likely it was that youngsters had asthma.

These studies are in direct contrast of what most doctors were telling their patients within the last several decades. The results of the study indicated that just 3 % of farm children had the common form of asthma called atopic and 4 percent had hay fever. In non-farming households, 6 percent had atopic asthma and almost 11 percent hay fever. This indicated that exposure to farming in the first year of life was especially protective. In the U.S., the asthma rate rose about 74 percent between 1980 and 1996 but decreased slightly by 1999, the most recent year available, according to the Centers for Disease Control and Prevention. About 10.5 million Americans have asthma, and 24.8 million have hay fever. These findings, joined with similar findings from other studies, have borne a whole new form of thinking and theory. The idea is recognized as the "hygiene hypothesis". It holds that early exposure to some germs arms the maturing immune system against some allergic conditions. Some research, in fact, has suggested that children who are exposed early on to pets or to lots of other youngsters at day care are less likely to get colds or allergies later on. Supporters of the new theory suspect that indoor plumbing, cleaner and more airtight homes, and antibiotics have contributed to an explosion in allergies in industrialized countries.

Back to Articles List