Asthma affects about 7 million children in America, and up to half of all children will develop wheezing by the time they are 3, putting them at a higher risk of later getting full-blown asthma. 

So where do pet dander, mouse droppings, cockroach allergens, and other bacteria come into play? Studies link higher rates of asthma to children living in houses with higher amounts of these substances — but with a catch. If infants below the age of 1 are exposed to pet dander, mice droppings, and roach allergens, they are much less likely to develop asthma! 

A study published in the Journal of Allergy and Clinical Immunology followed the health of 467 inner city newborns from Baltimore, Boston, New York, and St. Louis, and many of their houses were studied for bacterial content in dust. They not only found that infants exposed to some of these specific bacteria have much less chance of getting asthma later in life, but they also found that those exposed to all three allergens (pet, mouse and cockroach) had even less chance of getting asthma. 

To give you some numbers, infants who weren't exposed to the three allergens had a 51 percent chance of developing wheezing. Infants who were exposed to all three allergens only had a 17 percent chance of developing wheezing. 

Researchers also found that infants in homes with the greatest variety of bacteria, and the highest levels of allergens were the least likely to later develop asthma. 

Quite frankly, mouse droppings and cockroaches gross me out to the fullest, especially in the house. But the question this brings up in my mind is this: What type of bacteria would our infants be exposed to if we slept in open tents in the wild? Is it possible that there we would also be exposed to a wide range of bacteria from a young age that could have a protective benefit later in life? 

It's an interesting thought. 

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