Researchers at the University of Colorado in the United States have found, after analyzing 1,200 homes, that houses have about 9,000 different species of microbes. This is the average of types of bacteria and fungi found in the dust of a common home.
The study is part of the project “The Wildlife of Our Houses“, in which volunteers sent samples of the dust accumulated in the gutters of the doors, places that are often ignored during a cleanup, scientists said.
“We have known for a long time that microbes inhabit our homes. What we are doing now is applying old and good science to see how they vary according to the space where they are found, “said Noah Fierer , a professor of ecology and evolutionary biology.
The team concluded that a common home usually has more than two thousand different types of fungi and that its type varies according to the location of the residence.
“Most of the fungi found apparently come from outside. They enter through clothing or through windows and open doors. So the best way to predict what kind of fungus lives in a house is to know where it is, “he added.
In addition, the researchers found an average of 7,000 different bacteria in each home . Some of them are related to the human skin, but were found species related to the feces. In this case, the variety depends not on the location of the residence, but on who inhabits it.
“We found different bacteria in women-occupied dwellings than in those inhabited only by men. There are types of bacteria usually associated with the female body rather than the male and we could see this in the dust, “he explained.
The presence of pets also influenced the variety of microbes.
“Having a cat or a dog has a significant impact on the types of bacteria found in a home. It was surprising for us to find such a big influence, bigger than any other factor. ”
Although the study was conducted in the United States, the scientist says the results are relevant to other parts of the world.
Now, researchers want to find out how these microorganisms can affect human health. Although some are linked to illnesses and allergies, most are probably harmless and may even be beneficial .
“People do not have to worry about microbes in their homes. They are all around us, in our skins, in our homes – and most of them do no harm, “concludes Fierer.