Background: Between January and September of 2019, 15 patients acquired Candida auris infection in our surgical intensive care unit (SICU). Although the outbreak was controlled by enhancing horizontal measures and a change of the environmental disinfectant from a quaternary ammonium compound to a peroxide-based product; we wanted to understand whether patient-to-patient spread was occurring or the environment was the major contributor. Methods: We submitted all the 15 isolates from clinical samples for WGS and phylogenetic analysis; along with operation theater (OT) and ICU environment random swabs for metagenomic analysis. DNA sample QC DNA extraction was done using a Qiagen QiAmp DNA mini kit (cat. no. 51306). The DNA samples were subjected to QIAXPERT and Qubit for quantifying the amount of DNA in the extracted sample. Also, the 260/280-nm ratio was examined for the purity of the same. They were also subjected for agarose gel electrophoresis. For the DNA library prep protocol, whole-genome libraries were prepared from 21 samples using NEBNext Ultra IITM DNA Library Prep Kit (Cat. No: E7645L). The adapter sequences were added to the ends of DNA fragments to generate paired-end libraries. The resulting adaptor-ligated libraries were purified and index tags were added by amplification, followed by purification. Libraries were assessed to check the quality and quantity using Agilent 2200 Tape station (cat. no. 3-PM 863NA). For the sequencing protocol, prepared libraries were quantified using Qubit High Sensitivity reagent. The obtained libraries were diluted to final concentration of 2 nm in 10 µL and were subjected to cluster amplification. Once the cluster generation was completed, the flow cells were loaded on to the sequencer. Sequencing was carried out in Hi Seq X10 to generate 2X150-bp sequence reads at >100X sequencing depth (~1.5 Gb). A minimum of 75% of the sequenced bases were of Q30 value. Sequenced data were processed to generate FASTQ files and were uploaded on the FTP server for download and secondary data analysis. Results: Overall, 2% of the DNA from the OT and SICU environment showed Candida auris. The phylogenetic analysis confirmed 2 different clusters. Furthermore, 13 of the clinical isolates belonged to the same cluster, confirming that patient-to-patient transmission had occurred, which was subsequently confirmed by line listing the patients. Conclusions:Candida auris can efficiently spread from patient to patient, resulting in outbreaks. It can also persist in the healthcare environment causing ongoing propagation of these outbreaks.

Funding: None

Disclosures: None