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Burn patients are susceptible to infections due to impaired natural defences when the epidermal barrier is damaged. Moreover, the trauma affects the patient's immune system through local and systemic inflammatory reactions. Adding to that, the need for intensive care treatment with multiple surgical interventions increases the risk of infection. The need for vascular, airway, etc. catheterisations further strains the burned patient. Microbes, especially those with extraordinary survival properties in the healthcare environment, are essential sources of infections in burn wounds.

This thesis aimed to investigate microbiological aspects in burn care, including bacterial colonisation, transmission and possible measures to combat this and reduce infection rates.

In paper I, we investigated Staphylococcus aureus-colonisation in burn patients. Thirty-nine (48.8%) patients were S. aureus positive, and 41 (51.3%) negative at admission. Whole-genome sequencing of the 53 (39 + 14) S. aureus positive showed that the patients carried unique isolates, most likely due to their flora at admission and not by cross-contamination.

In paper II, through a systematic investigation, we showed that higher awareness and education of contamination routes increased healthcare workers' compliance with hand hygiene and dress code. Intensified cleaning procedures of the environment and equipment could successfully be established, which significantly contributed to stopping the further spread of Acinetobacter baumannii in the burn unit.

In paper III, we observed that the decontamination-efficacy of Ultraviolet–C (UVC) of bacteria in fabrics in a clinical setting is not as effective as laundering and, thus, it´s not an alternative to UVC decontamination.

In paper IV, we established that received UVC dose varied with the device's location when decontaminating a wardroom. The validation of single-use UVC dose indicators showed their usefulness in ensuring adequate decontamination doses. 

This thesis shows that the patient’s colonisation of S. aureus during the burn treatment is primarily due to the S. aureus carried at admission and not due to transmission. It also shows that a high level of knowledge about transmission routes, infection prevention, and cleaning protocols is essential to burn care. Decontamination using UVC light seems a plausible adjunct to routine cleaning.