Multidrug-resistant microorganisms (MDR) can be found on medical equipment and surfaces near patients and may be related to hospital outbreaks. Frequent and adequate cleaning contributes to reduction of microbial load and MDR dissemination in healthcare services.

To evaluate the impact of a multimodal intervention on professional adherence to cleaning practices and environmental contamination rates by MDR.

Quasi-experimental study conducted in six adult ICUs in Greater São Paulo, developed in three periods: pre-intervention (08/01/23–10/31/23); multimodal intervention (11/01/23–04/31/24); and post-intervention (05/01/24–10/31/24). During the first period, professionals maintained routine cleaning. The intervention included training, provision of cleaning supplies (one disinfectant solution per bed, disposable multiuse cloths), and feedback on cleaning assessment results. During this period, professionals participated in evaluation of cleaning performed by researchers. In the post-intervention period, implemented measures were maintained. Cleaning assessment used a fluorescent substance applied to 10 predefined high-touch points and evaluated with ultraviolet light. Cleaning was considered compliant when all marked points showed no fluorescence or substantial reduction of the fluorescent marker. Environmental contamination assessment involved cultures collected from the same 10 high-touch points. Samples were collected monthly from two beds per ICU.

A total of 2,587 cleaning evaluations were performed. Mean adherence rates by study period were 15.67%, 51.33%, and 74%, respectively (p < 0.001). Environmental contamination rates were 14%, 6.8%, and 5.5%, respectively. There was a reduction in surface contamination by Acinetobacter baumannii from 9% to 3.5% (p > 0.05) and by Klebsiella pneumoniae from 16% to 4.17% (p < 0.05) when comparing pre- and post-intervention periods. Bed rails were the surfaces most frequently contaminated by MDR.

Monitoring cleaning using fluorescent markers combined with a multimodal educational program contributed to improved professional cleaning practices and reduced environmental contamination rates by MDR, particularly K. pneumoniae.