Background
Sciensano, the Belgian institute for health, analyses data on antimicrobial resistance collected from Belgian acute carehospitals (n=103 mergers in 2022). The first national surveillance program for methicillin resistant
Staphylococcus aureus
(MRSA) was initiated in 1994. Initially, participation in this surveillance was voluntary, but became mandatory in 2006.
Methods
Data, aggregated at hospital level, are collected retrospectively in the following year by hospital’s microbiology laboratoriesand/or infection prevention and control (IPC) teams. Both invasive and non-invasive samples are included and each patientis counted only once per hospitalisation period. Healthcare-associated (HA-)MRSA is defined as MRSAcolonization/infection considered to be acquired in the hospital (first positive sample collected more than 48 hours afteradmission), and not known from the patient’s history (past 12 months).
Results
The incidence of MRSA peaked in 2005 (6.3 cases per 1000 admissions; Figure 1), but shows a decreasing trend ever since(2005-2022 incidence rate ratio (IRR)=0.915, 95%CI: 0.912-0.918; p<0.001). The incidence of HA-MRSA was highest at thestart of the surveillance (3.7 cases per 1000 admissions) with a second peak in 2004 (2.9 per 1000 admissions), but thendecreased year-on-year to 0.2 cases per 1000 admissions in 2022 (1994-2022 IRR=0.879, 95%CI: 0.876-0.882; p<0.001). Theproportion of HA-MRSA on the total number of MRSA fell from 78.6% in 1994 to 43.1% in 2006 and is currently at its lowest(15.6%).
Conclusions
Over the past three decades, the evolution of (HA-)MRSA in Belgium has mirrored global trends. Initially confined tohealthcare settings, MRSA presented a significant challenge in hospitals and long-term care facilities (LTCFs) during the1990s. Combined efforts of the IPC teams and targeted actions such as national hand hygiene campaigns (since 2005),specific guidelines (2004), more focused screening policies and multidrug resistant microorganism carrier studies in LTCFshave been pivotal in mitigating the impact of MRSA in Belgian healthcare facilities. From 2000 onwards, community- andlivestock-associated MRSA emerged. Recently, a virulent
eta/etb
impetigo-related MRSA resistant to fusidic acid, firstdescribed in the Netherlands, was detected in Belgium.