Antimicrobial resistance is a public health problem with global impact.

To implement a bundle of measures for monitoring and preventing the dissemination of multidrug-resistant bacteria in two Brazilian public hospitals and to monitor outcomes during the pre-intervention (Jun/23–Feb/24) and post-intervention (Mar/24–Nov/24) periods.

Hospital A included an Intensive Care Unit (ICU) with 20 beds and a hematology unit (20 beds). Hospital B included an Emergency ICU (10 beds) and a clinical ward (39 beds). The bundle included surveillance of carbapenem-resistant Klebsiella pneumoniae (CR-KP) and carbapenem-resistant Acinetobacter baumannii (CR-AB) through admission and weekly rectal swabs; monitoring of hand hygiene adherence; contact precautions; environmental cleaning and disinfection; technical visits by specialists; an educational program via a web platform; and biweekly monitoring of indicators. All data were recorded in specific RedCap forms.

A total of 3,130 patients were included, with 4,021 care records. Admission rectal swabs were collected in 70% (2,805) of all records, with positivity rates of 2.6% for CR-AB, 9.6% for CR-KP, and 2.2% for simultaneous CR-KP and CR-AB. The incidence density of CR-KP and CR-AB was 8.7 and 3.7 per 1,000 patient-days in the pre-intervention period, and 12.98 and 3.65 per 1,000 patient-days in the post-intervention period, respectively. Between periods, hand hygiene adherence improved from 50% (3,324/6,661) to 58% (4,900/8,485), as did compliance with surface cleaning and disinfection from 52.5% (1,889/3,483) to 64.7% (2,420/3,742). Regarding contact precautions, improvements were observed in stethoscope disinfection between patients (37.6% [71/189] to 81.2% [211/260]), appropriate use of personal protective equipment (45.8% [447/977] to 65.1% [545/837]), and glove change between contaminated and clean sites (35% [82/234] to 65.1% [545/837]).

There was improvement in antimicrobial resistance surveillance and gradual adherence to the prevention bundle throughout the study. However, a reduction in the incidence of new cases was not observed, likely due to unmeasured limitations such as patient-to-staff ratio, colonization pressure, irregular supply of preventive materials, and gaps in professional training.