One hospital has undergone comprehensive assessment – a hospital building within the University of Chicago. This began in 2013 when a research group undertook swabbing of various nooks and crannies, and subjected the samples to genetic testing. The aim was to construct a map of the hospital microbiome (where microbiome refers to the microorganisms and their genetic material within a given ecological niche).
The Chicago project forms part of a wider initiative called the Hospital Microbiome Project. The reason relates to an assessment of infection risk from specific environments. The U.S. Centers for Disease Control and Prevention has identified 1.5 million cases of environmentally-contracted notifiable diseases in the U.S., of which 15,743 resulted in death (around 1 percent.)
How microbial communities persist and change in indoor environments is of immense interest to public health bodies and scientists, and there is sufficient data to suggest that different types of setting differ significantly (in that a hospital will differ to a restaurant) and that different geographical areas will also show significant differences in microbial population and diversity. Differences arise from building materials; air handling systems; and the human population residing within the built environment.
When people are in hospital, as patients, their immune system is often weakened, meaning patients can be prone to infections. Research suggests that hospital-acquired infections (or ‘nosocomial infections’) are typically acquired between 48 hours and 4 days after a patient has been admitted to the hospital. The infection rates vary globally; in the U.S. the infection rate is around 5 percent of the patient population.
Until the new project was launched been no systematic analysis of the source, presence, and development of either pathogenic or non-pathogenic microbial reservoirs in hospital environments. The purpose of such an analysis is to understand the extent of pathogenic organisms (and the degree to which these are antimicrobial resistant) and the areas within the hospital where they are most commonly found. By gaining such knowledge, cleaning can be better targeted or personnel practices can be reviewed. Such data can also assist with building design allowing for a review of physical conditions (such as humidity or temperature), as well as building materials.
Other areas of interest include:
Differences between patient population, and whether duration of stay makes a difference.
The number of patients to a ward.
What influence medical and healthcare personnel have in influencing the microbiome.
How microbial communities change over time.
What the ‘natural’ microbial community is compared to that introduced by patients or staff.
Discussing this further, Jack Gilbert, a leader of the Hospital Microbiome Project and a microbial ecologist at Argonne National Laboratory told The Atlantic: “There are many unexplained diseases that occur in hospitals—sepsis, infections—and although we can identify a bacterium most associated with those events, we still fail to understand the specifics of the transfer of organisms in the hospital.”
The findings have yet to be published in a peer reviewed journal reveal that certain types of bacteria commonly found on human skin, such as some species of Staphylococcus, Streptococcus, and Corynebacterium, became much more abundant after the hospital opened. Meanwhile, a pathogen like some species of Pseudomonas, which can cause bladder, wound, and lung infections, became less plentiful. That indicates the hospital environment is largely shaped by the humans within it, and the way people interact fosters the exchange of bacteria.
