BACKGROUND: Antimicrobial resistance (AMR) is a major global threat. The World Health Organization (WHO) has identified key organisms that carry the potential for both pathogenicity and AMR, leading to reduced treatment options and worsened outcomes, through the Global Antimicrobial Resistance and Use Surveillance System (GLASS). In Timor-Leste, surveillance is now possible due to significant gains in diagnostic capacity.

METHODS: In 2020-2021 a cross-sectional surveillance study was performed on inpatients and outpatients across all hospitals in Timor-Leste. Nose/axilla/groin swabs were selectively cultured for Staphylococcus aureus and methicillin-resistant S. aureus (MRSA); rectal/perianal swabs for extended spectrum beta-lactamase (ESBL) producing organisms and on MacConkey agar with ciprofloxacin and gentamicin discs. S. aureus, Escherichia coli and Klebsiella pneumoniae isolates were assessed for resistance; univariate and multivariable analyses assessed for associations.

RESULTS: 516/517 had Gram-positive bacteria screening. S. aureus was detected in 93 (18.0%), 14 (15.1%) of which were MRSA, representing 2.7% MRSA carriage. 511/517 were screened for Gram-negative organisms; 108 (21.1%) cultured at least one ESBL-producing organism; ciprofloxacin resistance was found in 109 (21.3%) and gentamicin resistance in 77 (15.1%). Only one carbapenem-resistant organism (an Acinetobacter baumannii) was detected. Participants in Dili were more likely to be colonised with resistant Gram-negative bacteria (aOR 5.3 ESBL, aOR 3.5 ciprofloxacin resistance, aOR 2.7 gentamicin resistance). Being an inpatient was associated with gentamicin resistance (aOR 2.9); dog ownership was associated with ESBL carriage (aOR 1.9).

CONCLUSIONS: ESBL, ciprofloxacin and gentamicin resistance carriage rates were high, particularly in Dili. MRSA carriage and carbapenem resistance were reassuringly low. Ongoing surveillance is essential to monitor AMR and inform guideline development.