Can screening and decontamination procedures performed on an outpatient basis reduce the colonization with Staphylococcus aureus and mitigate associated complications in patients undergoing elective hospital procedures? A controlled intervention study (STAUfrei).

Background: Staphylococcus aureus (SA) colonisation increases the risk of wound infections in surgical procedures. Prevention strategies to date have focused primarily on the hospital, although there are recommendations for pre-hospital decontamination at home, which can be performed by patients themselves. The current study aimed to shift the process of screening and decontamination of SA (methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA)) out of the hospital setting.

Methods: Between April 2019 and March 2022, N=8054 (Intervention Group=3390) patients (>18 years) undergoing elective procedures in a hospital in Baden-Württemberg (Germany) were recruited for the study. The intervention consisted of a 5-day decontamination carried out by patients (or their caregivers) in their domestic environment. The analysis comprised a simple arm comparison of colonisation rates at admission between study groups as well as adjusted logistic regressions.

Results: After adjustment for relevant risk factors the intervention reduced the risk of SA colonisation at admission statistically significant by 14% (odds ratio: 0.86 (95 % CI: 0.74-0.10; p= 0.046). Rehospitalizations were also significantly less frequent in the intervention group. Signs of wound infection and recolonisation after invasive procedures did not differ significantly between the study groups.

Conclusions: The outpatient decontamination measures point towards effectiveness compared to routine care. As results from logistic regressions are based on the Methicillin-Sensitive SA (MSSA), considering it in clinical hygiene management should be discussed. Strict adherence during the pandemic was challenging, potentially underestimating the intervention's overall impact.