In the nineties, Erika von Mutius was one of the founders of hygiene hypothesis. Not an excess of dirt is primarily due to the increase of allergy and asthma. But a lack of natural dirt. In conversation, Germany’s leading asthma researcher explains how to prevent the national disease.
Asthma can be prevented, you have recently discovered with colleagues: if you live like a peasant in the 19th century. How would you describe that?
Just like on a time trip, so my visit to the Amish people in America actually occurred to me. They have no machines, no electricity, they use horse-drawn carriages instead of cars. We have compared this community with another, separated group, the Hutterians. The latter have similar genetic roots, similar living conditions, but six times higher asthmarates. This is enormous. While the Hutterians operate a modern agriculture, the Amish have always maintained their traditional methods, including very close contact with animals. Mothers take the children as babies into the stable, from there microbes are also carried home. This form of coexistence is probably the reason why the amics rarely develop hay fever or asthma.
How can this be explained?
I believe that the contact with possible allergens always depends on the context. To this end, one must know that the innate immune system of a child reacts first to all microbes that are found in the environment. The defense cells need only a certain training in order to be able to distinguish: signals a new, so-called antigen danger, which must be repelled? Or is it completely harmless? With this classification, it is, in my opinion, crucial in which context our immune system, for example, learns pollen. A pollinated corn polluted with pollutants from car exhaust gases is interpreted quite differently from the one encountered by the immune cells near a cow house.
At what age does the training of the immune system take place?
Of particular importance are the first three years of life. But it has also happened during pregnancy, which we observed in studies. When a farmer works in the stable, her child shows another immune response at birth. It is also important that the contact takes place over a certain period of time: the longer, the more solid the effect. Three weeks of holiday in the country are certainly not enough. For an excellent idea, however, I think the model of kindergarten on the farm, which is becoming more and more popular. Children do not always have to live among animals, already the contact as neighbor can reach.
What could German parents look like from the Amish?
Nothing, I’m afraid. You can neither turn the clock back nor take a cow home with you. The dirt in the barn is different from that in the town; If a child is eating dirt in the playground, it will not get the same protection. In Munich, we have also looked at whether the personal hygienic behavior makes a difference. To what extent does it matter how often someone is washing his hair, cutting his nails, and how clean the household is? All of this has nothing to do with allergy and asthma, we had to conclude.
Nevertheless, your studies could be summarized as a positive message: prevention is possible.
Yes that’s true. The development of an asthma disease is likely to be prevented if we learn to understand the mechanisms of nature better. We have the appropriate proofs, we also have the appropriate animal models. Now we just have to rauskriegen what exactly in the stable is responsible for these effects.
In order to prevent asthma and allergies, a lot has already been propagated. What does it really help?