What is the microbiome of the human home?

There is currently little known about the range and diversity of microorganisms in the indoor home, particularly in the context of modern airtight homes. People spend a great deal of time in their homes, especially those at the extremes of age, and it is possible that the indoor microbiome could impact upon human health in ways not yet understood. This project aimed to systematically screen sites in 100 houses in the Lanarkshire community in order to determine the amount and type of cultivable aerobic bacteria and fungi in the home. It was hoped to be able to characterise the microbiome of the ?normal? home. Chosen sites were: indoor bathroom handle; telephone; kettle handle; bedside table; top of bedroom door; TV remote; toilet handle; and bedroom window sill (Table 1). These sites were screened using double-sided dipslides coated with nutrient and staphylococcal selective agars (Figure 1). Bacteria and fungi were quantified for each site and staphylococci and Gram- negative bacilli identified if possible. Each of the eight sampled sites revealed its own distinct microbiological character, both in the type and amount of cultivable microbes. Human pathogens, particularly S.aureus, were more likely to be associated with commonly touched sites such as TV remote, kettle handle and telephone. Whole houses also demonstrated unique microbiological characteristics, with morphologically similar and identifiable microbes observed at multiple sites within the same home. Each home thus displayed it own unique microbiome but with identifiable similarities between other homes according to site.