Microbiome Interactions in Healthcare Settings
Tracks
Meeting Room 1.40
| Monday, June 30, 2025 |
| 12:30 PM - 1:00 PM |
Overview
Speaker: Dr Kalisvar Marimuthu
Speaker
Dr Kalisvar Marimuthu
Communicable Diseases Agency
Microbiome Interactions in Healthcare Settings
Abstract
The hospital environment is more than a passive backdrop—it is an active and complex ecosystem that influences pathogen transmission. In this talk, I will explore how metagenomic approaches are reshaping our understanding of the hospital microbiome and its role in healthcare-associated infections (HAIs).
Our studies in a tertiary care hospital in Singapore revealed distinct ecological niches in high-touch surfaces (CTA) versus wet, plumbing-associated areas (CTB). CTA sites exhibited greater microbial diversity and turnover, while CTB sites harboured stable biofilm-forming bacteria. Importantly, antibiotic resistance genes were distributed differently across these zones, with some key carbapenemase genes more prevalent in hidden, low-touch reservoirs.
Building on this, national genomic surveillance showed that while clonal transmission of carbapenemase-producing Enterobacterales (CPE) declined with infection prevention and control (IPC) interventions, plasmid-mediated transmission persisted—likely sustained by environmental reservoirs.
These findings call for a shift in IPC strategies to recognise and address the hospital microbiome’s hidden dynamics. A deeper understanding of environmental reservoirs is crucial to tackling antimicrobial resistance and advancing effective IPC in the genomic era.
Our studies in a tertiary care hospital in Singapore revealed distinct ecological niches in high-touch surfaces (CTA) versus wet, plumbing-associated areas (CTB). CTA sites exhibited greater microbial diversity and turnover, while CTB sites harboured stable biofilm-forming bacteria. Importantly, antibiotic resistance genes were distributed differently across these zones, with some key carbapenemase genes more prevalent in hidden, low-touch reservoirs.
Building on this, national genomic surveillance showed that while clonal transmission of carbapenemase-producing Enterobacterales (CPE) declined with infection prevention and control (IPC) interventions, plasmid-mediated transmission persisted—likely sustained by environmental reservoirs.
These findings call for a shift in IPC strategies to recognise and address the hospital microbiome’s hidden dynamics. A deeper understanding of environmental reservoirs is crucial to tackling antimicrobial resistance and advancing effective IPC in the genomic era.
Biography
Dr. Kalisvar Marimuthu is the head of the Infection Prevention, Control, and Outreach (ICON) division at the National Centre for Infectious Diseases and serves as a Senior Consultant in Infectious Diseases at Tan Tock Seng Hospital, Singapore. He chairs the National Infection Prevention and Control Committee (NIPC) of Singapore.
Dr. Marimuthu completed his advanced speciality training in Internal Medicine and Infectious Diseases in Singapore in 2010 and 2013, respectively. He trained as a Senior Research Fellow in the IPC Unit at Geneva University Hospital.
Dr. Marimuthu’s research revolves around the transmission dynamics of emerging infectious diseases and multidrug-resistant organisms. His work extends to healthcare-associated infection (HAI) surveillance and prevention strategies, with a special focus on leveraging genomics in infection prevention and control (IPC).
