THE ROOT OF ALL ASTHMA Ioana Esanu investigates if the hygiene hypothesis plays a role in developing asthma.
The human body is a wondrous thing. From organelles to cells to tissues and organs, you are a magical machine running mostly on oxygen and sugar.
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989. The Berlin Wall falls. Two sides of the same nation reunite, and just like that, the perfect opportunity arises for scientists across Germany. They could finally compare the effects of an Eastern versus a Western lifestyle on a large control group of genetically similar individuals. It was thus that Erika von Mutius discovered a rather strange occurrence. Children who had grown up in heavily polluted East Germany were much less likely to suffer from asthma or atopy compared to children growing up in well-developed West Germany. And this was not just some anomaly. 8,750km away, in Hong Kong, asthma rates are up to 15%. Little more than an hour away, in much more polluted Guangzhou, only about 3% of citizens suffer from the disease. The Hygiene Hypothesis Coincidence? Not really. Rather, a widespread theory known as the “hygiene hypothesis”. The origin of the theory lies in the London School of Hygiene and Tropical Medicine, where epidemiologist David Strachan concluded that the sanitary Western lifestyle might come with its disadvantages. People in the Western world are much less exposed to germs and other pathogens than those in low-land middle-income countries. Cleanliness and sanitation, key aspects of a developed nation, seem to have made our bodies more prone to allergies (and indeed asthma). The reduced exposure to infectious agents in childhood is believed to increase the likelihood of developing such diseases in adulthood. Once popular in the 1990s, the hygiene hypothesis is now standing on its last leg, as more and more statistics disprove it. In 2004, the Global Initiative for Asthma reported the prevalence of clinical asthma around the world, and a few surprises arose. South American countries like Brazil, Peru and Costa Rica recorded some of the highest numbers, even though pollution was high and sanitation was poor – their exposure to pathogens had not protected them against asthma. On the other end of the spectrum, hyper-hygienic Japan and Scandinavia had a moderate incidence of the disease, meaning that the cleanliness had not impacted their
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chance of atopy. All in all, scientists agree that there is more at work than just germs and dirty playgrounds. Breathing Matter What is the difference between children today and 70 years ago? TikTok. Or more generally, technology. When you think back to your afternoon schedule in primary school, you likely picture yourself sitting cross-legged on the floor in front of the TV. Your grandparents remember something else entirely: playing outside with their friends and running around until they had to be dragged back into the house. Thomas Platts-Mills, of the University of Virginia, claims there is a direct correlation between sedentarism and asthma rates. The USA saw a rise in cases after children’s TV shows became widespread – such as the Mickey Mouse Club in the mid-1950s.
and Rothia. It is interesting to note how babies actually acquire these microbes. Most of the time, they gather them from the surrounding environment. Others are unable to do so, due to circumstances of their birth, antibiotic exposure, and even lack of breastfeeding. The Pandemic Now this is all very interesting, but why should we care? After all, doctors understand
Platts-Mills’ research shows that the human body experiences a wholly different breathing pattern when watching TV compared to when reading, or more obviously, when exercising. A TV-watching child will sigh less and take shorter breaths, which in time will damage the smooth muscle in the bronchioles. This underactivity of the lungs is believed to increase the risk of asthma. What’s more, if a patient develops asthma as a result of their sedentary lifestyle, changing their habits will likely not improve their condition, but rather aggravate it. Exercising is one of the main triggers of an asthma attack, resulting in wheezing and shortness of breath. Have You Got the Guts? The human body is a wondrous thing. From organelles to cells to tissues and organs, you are a magical machine running mostly on oxygen and sugar. And it just so happens that most of you is not you, but rather bacteria. A few dozen trillion of them – good and bad – play a part in your life in many subtle ways. A recent human study from the University of British Columbia reveals that the first 100 days of life of an infant may be crucial to their likelihood of developing asthma. There are 4 gut microbes whose absence in infancy may cause the disease in later childhood: Lachnospira, Veillonella, Faecalibacterium,
artwork: Laurane Le Goff, Mantis Laurane Le Goff, Trametes Versicolor
