The Dirt on Clean - Katherine Ashenburg [103]
On a very real level, germs concern us because the world has become a significantly more perilous place of late. In recent years, many normal activities, such as eating beef and chicken, travelling on public transit and being treated in a hospital, have turned out to be extremely dangerous in certain places. Arrogantly and ignorantly, we assumed that epidemics such as the Spanish flu of 1918 could not happen again. SARS proved us wrong, and now we dread bird flu or a yet unnamed pandemic. Our fearfulness is heightened rather than lessened by the abundance of information and misinformation available at our fingertips on the Internet.
The Clean Shopper prevents babies from touching germ-laden supermarket carts.
On a more symbolic level, since September 11, 2001, we know that we live in a world that harbours deadly, hidden dangers—terrorists are like germs in that way. The American writer Allen Salkin asks, “Is it only a coincidence that the same places where Americans most fear terrorism—airplanes, schools, mass transit, water supplies and computers—they also fear germs?” Probably not, and what at least some of this overwrought avoidance of germs really demonstrates is our wish to be protected, to be safe in a world that seems increasingly unsafe.
In 2006, the Museum of Modern Art in New York City was selling some unlikely stuffed toys in its gift shop. Not lambs or bunnies, they were microbes—a dust mite, a bedbug, a stomach ache virus and a common cold virus. These cuddly playthings in bright colours were perplexing: are microbes our friends? For 125 years, educated opinion would have said no. Now, surprisingly and with increasing frequency, the answer seems to be “some of them” and “sometimes.”
Cleanliness in the twenty—first century has more than one face. While some of its aspects, such as the new germ phobia, are charging ahead in one direction, others stand still or take some steps in the opposite direction. The most unexpected example in the last category began surfacing almost twenty years ago. In 1989, a British epidemiologist, D. P. Strachan, published a groundbreaking article in the British Medical Journal called “Hay Fever, Hygiene, and Household Size.” In it, he suggested that unhygienic contact and infections, both of which are facilitated by large families, might prevent the development of allergies. The so—called Hygiene Hypothesis, first voiced by Strachan, is that our immune system needs a certain amount of bacteria on which to flex its muscles. Deprived of it, the white cells that are designed to fight bacteria, called ThI lymphocytes, fail to develop, and the other white cells, Th2 lymphocytes—those designed to make antibodies to defend the body against microbial dangers as well as to produce allergic reaction—will take over.
That imbalance in the two types of white cells is “like a set of scales that sometimes tips sharply enough to send a person’s health tumbling,” as a science writer, Siri Carpenter, put it. Without the check of healthy ThI lymphocytes, “the Th2 system flourishes and the immune system teeters toward allergic responses.” In the view of Strachan and the dozens of researchers who followed him in trying to understand the late twentieth century’s baffling rise in asthma and other allergies, the likely culprit is the scrupulous cleanliness of the developed world. Unlike Dr. Gerba, who seeks to eliminate or avoid bacteria as much as possible, these scientists see value in bacteria.
Also in the late 1980s, a German doctor, Erika von Mutius, compared the incidence of allergies and asthma in children from East Berlin and West Berlin. She expected to find that children living in unhygienic, polluted and economically disadvantaged East Berlin would have higher rates than the children from the same genetic background who lived in clean, prosperous West Berlin. She found just the opposite. The West Berlin children had significantly more asthma and allergic reactions.
The research of von Mutius, Strachan and others interested in