Diverse microbial communities share our lives. They are found in our offices, gardens, homes, and of course in our own bodies. In a landmark study published in Proceedings B this week, the ecology of these communities in our homes has been mapped.
Collecting data via the citizen science project Wild Life of our Homes, researchers were able to identify differences and similarities in fungal and bacterial communities in our homes, and correlate these with biogeographic and local factors. Volunteers from over 1100 homes across the USA provided dust samples from upper door trims inside and outside of the house (these being the places least likely to be cleaned frequently) for the study. The same volunteers provided information about the inhabitants of the house – human and non-human – as well as the location which were then tested as predictors of bacterial and fungal species.
While the samples taken inside and outside the homes showed distinct communities, this was more pronounced for bacteria than for fungi. A large proportion of fungal microbes found indoors had outdoor origins and thus often matched the fungal community found outside of the same house. The fungal communities also showed distinct differences in biogeography, with certain types of fungi being more prevalent in particular geographic areas.
On the other hand, bacterial communities were more strongly influenced by the number and types of occupants in the home. This included the gender of inhabitants, as well as the presence of pets, and can have a predictable influence on the bacterial communities found in homes.
The study concludes that if you want to change your fungal exposure you need to move house (to somewhere far away) and to alter your bacterial exposure you need to get new housemates. Although, it’s probably easier to just do the cleaning…