Trillions of bacteria colonise the human body. Collectively, these bacteria are called the human microbiome. Most bacteria of our microbiome are harmless or even beneficial to our health. However, bacteria that can cause infections are also part of the microbiome. In healthy individuals the immune system keeps these bacteria at bay, but patients in hospitals frequently develop infections with bacteria from their own microbiome. These infections are often difficult to treat as antibiotic resistance is particularly widespread among this group of bacteria.
In a recent study, Professor Van Schaik, with collaborators in the Netherlands and Finland, performed a study on the microbiome of patients in Intensive Care Units (ITUs). The gut microbiome of ITU patients was found to change rapidly after admittance to the ITU, presumably due to the patients’ critical illness and the use of antibiotics. Genes conferring antibiotic resistance were abundant in the patients’ microbiome, but, due to a novel therapy aimed at reducing infections in ITU patients, levels of the ‘hospital bug’ Escherichia coli remained low. The results of this study are used for the development of interventions that minimise or prevent the presence of antibiotic-resistant bacteria in the gut microbiome of critically ill patients, which, in turn, will reduce the number of hospital-acquired infections in these patients.