Hand hygiene and the use of personal protective equipment (PPE) are among the recommended measures to prevent the spread of antimicrobial multidrug-resistant microorganisms (MDR) in health services. Objectives: To evaluate the impact of a multimodal intervention on hand hygiene practices, PPE use by health professionals, HAI density, and patient colonization by MDR.

A quasi-experimental study conducted in an adult ICU at a hospital in São Paulo, developed over three periods: pre-intervention (08/01–10/31/2023), multimodal intervention (11/01/2023–04/30/2024), and post-intervention (05/01–10/31/2024). In the first period, professionals maintained their usual hand hygiene and PPE practices for MDR contact precautions. During the intervention, trainings were conducted; educational videos and leaflets were provided; supplies for hand hygiene were made available (one bottle of alcohol gel per bed); reminder posters were placed in the unit; and feedback on evaluation results was given. In the post period, the implemented measures were maintained. Hand hygiene was considered “compliant” when performed according to the WHO’s 5 moments and without wearing jewelry/adornments. PPE use was considered “compliant” when the correct sequence of donning and/or doffing was observed. HAIs were reported according to ANVISA criteria. To identify patients colonized with MDR, rectal swabs were collected upon ICU admission and weekly until discharge. ICU-acquired colonization was defined as a positive culture from the 3rd day of ICU stay onward.

A total of 1,188 hand hygiene evaluations were performed; mean adherence by study period was 50%, 52.67%, and 66.5% (p > 0.05), respectively. Regarding PPE use, 356 observations were made; means were 32.33%, 46.17%, and 45.17% (p = NS). Mean HAI densities due to MDR per 1,000 patient-days were 2.23, 5.45, and 3.83 (p = NS). Mean MDR colonization densities per 1,000 patient-days were 19.5, 11.43, and 8.03 (p < 0.001).

The multimodal intervention contributed to better professional practices related to HAI prevention measures and had a significant impact on reducing MDR colonization density.