Mrs Elizabeth Orr1, Associate Professor Caroline Marshall1,2, Associate Professor Deborah Williamson1,2,3, Mr Ian Christie1, Mr Sven Denton4
1Melbourne Health, Parkville, Australia,
2University of Melbourne, Parkville, Australia,
3Microbiological Diagnostic Unit Public Health Laboratory, Parkville, Australia,
4AquaKlar Analytical Services, Thornbury, Australia
Burkholderia cepacia can cause outbreaks from contaminated fluids, especially in immunocompromised patients and ICU settings. From 1/12/2018 to 13/1/2019, we were notified of 15 B. cepacia isolates in blood, urine, respiratory samples and swabs in 6 patients across three pods in our 32 bed adult ICU. After the second patient notification on 17th December, an outbreak investigation was initiated.
Isolates underwent whole genome sequencing (WGS) and in silico multilocus sequence typing (MLST) to Melbourne Diagnostic Unit Public Health Laboratory. We sampled 12 faucet and aerators swabs, six tap water and 25 clinical environmental fluids including mouth wash, eye drops, ultrasound gel and hand wash from rooms where positive clinical isolates were detected and tested for B. cepacia. Beds were closed once positive patients were discharged from ICU, pending results.
B. cepacia species were detected in two water samples and five faucets and aerators swabs. None of the clinical environmental fluids sampled were positive. On notification of positive water, sink and faucet samples, thermal disinfection of the thermostatic mixing valves and the water system was conducted within the ICU. Repeat water, aerator and faucet samples were negative for B. cepacia. MLST and phylogenetic analysis revealed a relationship between patient isolates and their corresponding water, faucet or aerator samples. There was no relationship between patient isolates. The cluster resolved rapidly 1 month after identification.
In conclusion, rapid identification, WGS and environmental sampling facilitated a rapid response to resolve a small B. cepacia cluster. Following thermal disinfection, no further clinical isolates were detected.
Elizabeth Orr is the Manager of the Infection Prevention and Surveillance Service at Melbourne Health. She has previously worked in Infection Prevention roles at Austin Health, Hand Hygiene Australia, VICNISS and Monash Health. Elizabeth aims to empower her team to promote resilience to drive change in practice and to challenge the status quo. She loves spending time with family and of course chocolate.