P99 Prevalence of carbapenemase-producing bacteria colonizing hospital surfaces in low- and middle-income countries

Background
Antimicrobial resistance (AMR) is one of the fastest growing threats to global human health. Neonates are particularly vulnerable to AMR infections and this problem is exacerbated in LMICs where access to healthcare services and resources including antibiotics are limited. Carbapenem-resistant infections are a major healthcare challenge as carbapenems are often a last-line defence against MDR infections. Bacteria colonizing hospital environments serve as a reservoir of- and potential transmission risk for nosocomial infections.

Objectives
Determine the prevalence of carbapenemase-producing bacterial species colonizing hospital surfaces in neonatal, maternity and delivery wards in 13 hospitals across Bangladesh, Pakistan and Nigeria overall, by surface type and by facility.

Methods
High-touch and low-touch hospital surfaces across 13 hospitals in Bangladesh, Pakistan and Nigeria were sampled on-site using sterile cotton swabs and saline monthly over three consecutive months. Swabs were stored using Amies charcoal media and transported to the UK where they were cultured for 24–48 h at 37°C on antibiotic-supplemented (vancomycin and ertapenem) and non-supplemented chromatic detection agar media (Liofilchem®). Species from bacterial growth from non-supplemented agar were identified via MALDI-TOF MS and PCR was employed for samples with growth on agar supplemented with vancomycin and ertapenem to screen for carbapenemase genes blaNDM, blaKPC, blaOXA-48-like, blaVIM and blaIMP.

Results
A total of 1854 hospital surface samples have been processed to date. Microbial growth was obtained from n=1636/1854 surface samples. The most common species cultured were Pseudomonas stutzeri (n=717/1854), Enterobacter hormaechei (n=165/1854) and Klebsiella pneumoniae (n=135/1854). Carbapenemase-producing isolates (n=744) were found in n=476/1854 surface samples, including blaNDM (n=249/1854), blaKPC (n=11/1854), blaOXA-48-like (n=60/1854), blaVIM (n=221/1854) and blaIMP (n=82/1854). The surfaces most commonly colonized by carbapenemase producers were in or around sinks including sink bowls/basins, taps and floors surrounding sinks. The species comprising the greatest number of isolates per gene were K. pneumoniae for blaNDM and blaKPC (n=59/394 and n=7/14, respectively), K. pneumoniae for blaOXA-48-like (n=21/76) and P. stutzeri for blaVIM and blaIMP: (n=122/263 and n=46/93, respectively).

Conclusions
The high contamination rate of hospital surfaces with clinically relevant bacterial species across African and Asian hospitals is concerning. The prevalence of species harbouring carbapenemase genes is also of particular concern in terms of neonatal sepsis as they may be providing a route of transmission for AMR infections to neonatal patients born and treated within the hospitals. Future work will include further hospital surface sampling in addition to performing comparisons between isolates from hospital surfaces and pathogens found to cause neonatal sepsis from the same hospital sites, to investigate potential transmission networks.