This past fall, experts gathered at an American Academy of Microbiology Colloquium in Washington, D.C. to discuss an important topic relevant to many parts of society: the microbiology of built environments. A summary of the experts’ answers to important questions surrounding this topic is now available as an FAQ report.
What, exactly, is the built environment? This is a term that refers to manmade structures – so this means buildings, of course, but also public transit, parking lots, playgrounds, and the infrastructure (water pipes, ventilation systems, etc.) that support these spaces. People in developed countries spend 90% of their time indoors, and the microbial occupants of these buildings are very different from those of unenclosed spaces. Not only are the temperature and humidity differently regulated indoors, but the microbial community is also highly influenced by the building’s inhabitants – humans, animals (think pets), and plants. The report covers important topics, from the range of built environment types to the variety of microbes that inhabit them (see left).
These microbial communities can influence our health and that of the surrounding environment. These indoor spaces contain many microbes from shed human microbiota, and some of these microbes can cause disease or confer antimicrobial resistance if passed to another person. This is a big concern in hospital and health-care environments, or places with immunocompromised residents, where susceptible people need to avoid unhealthy microbial exposure. These indoor microbes, combined with other exposures and genetic influences, also shape allergy and asthma development, demonstrating that we’re all products of our microbial environments.
A building’s health is also influenced by its resident microbes. Microbes, especially fungi, can contribute to structural deterioration if not kept in check. But indoor cleaning efforts can bias where microbial residents remain: less-frequently washed walls are more likely to harbor long-term microbial inhabitants than frequently-washed floors or countertops. Understanding who lives where can influence decisions about a building’s air and water systems, cleaning regimen, and inspection schedule.
Understanding the interaction of microbes and these built environments will also lead to changes in building structural materials and codes. For example, we know now that plaster is susceptible to fungal growth after flooding; knowing this, engineers and architects can choose other materials for building construction in flood-prone areas. More frequent maintenance of HVAC systems can minimize the number of fungal spores in the air we breathe. Better understanding of water systems and water treatment can prevent outbreaks of Legionella, Pseudomonas, and other water-dwelling bacteria – and these are only a few examples. With the recent call for a national microbiome initiative, we’re sure to learn more about the microbes that live with us and their effects on our lives. To learn more about the microbes of built environments, be sure to check out the full report!
Interested in learning more on this fascinating topic? Join the American Society of Microbiology Twitter account, @ASMicrobiology, on Thursday, May 19th from 10:00—11:00 am EST in a conversation about Microbes of the Built Environment! Use the hashtag #ASMChats to participate in the conversation!
-- Julie Wolf
All images were taken from the Academy FAQ Report