Methods

A Candida auris outbreak occurred in our Surgical Trauma Intensive Care Unit (STICU) in early 2023. Within one month, C. auris was identified in the Burn ICU (BICU). The facility is an 865-bed tertiary care center and ICUs are on different floors. The same providers work in both units. During this period, no patients were transferred from the STICU to the BICU. The clusters of C. auris occurred in the context of regional outbreaks of C. auris in other hospitals and post-acute care facilities.

The index patient in the BICU was identified when a tissue culture grew C. auris. Since the index patient had a prolonged hospitalization, point prevalence testing (PPT) was conducted. Testing was performed by skin swab of the bilateral axilla and groin with specimens sent to the health department for reverse transcription-polymerase chain reaction (RT-PCR) testing for C. auris. Testing was requested for all patients in the BICU weekly for 4 weeks and identified 1 colonized patient. ^{Reference Sanyaolu, Okorie, Marinkovic, Abbasi, Prakash and Mangat2} The PPT in the BICU was stopped when two consecutive weeks were negative. The cluster was considered resolved, and both patients were discharged. The STICU had a simultaneous outbreak, overlapping with phase 1, with 7 patients positive on PPT which resolved before phase two.

A second phase of the outbreak occurred 4 months later when a clinical culture grew C. auris. ^{Reference Lowe, Willey, O’Shaughnessy, Lee, Lum and Pike3} Prior to testing positive for C. auris, patient 3 was under expanded contact precautions (providers changed into clean hospital scrubs for entry) due to the vulnerability of the specialized skin grafts. Point prevalence testing began again in the BICU, with two additional colonized patients ^{Reference Alanio, Snell, Cordier, Desnos-Olivier, Dellière and Aissaoui4,Reference Patterson, Wyncoll, Patel, Ceesay, Newsholme and Chand5} identified. Weekly PPT continued in the BICU until two consecutive weeks were negative.

Historically, the BICU used a universal contact precaution strategy with gown and glove use. This was stopped during the COVID-19 Pandemic in early 2020 and not resumed until the second phase of the C. auris outbreak.

During the outbreak, infection prevention interventions included: strict contact isolation of all infected or colonized patients with door monitors to enforce adherence, enhanced environmental cleaning of common areas and rooms with a hydrogen-peroxide-peracetic acid combination, which is on the Environmental Protection Agency’s list of P Agents that are active against C. auris. The floors were cleaned with detergent. For rooms housing a C. auris infected/colonized patient, the floors were cleaned with a hydrogen-peroxide-peracetic acid solution and the floor with detergent. Infection preventionists directly observed terminal cleaning using a hydrogen-peroxide-peracetic acid combination for the room and floors. Cleaning was validated with adenosine triphosphate (ATP) testing before ultraviolet wavelength C (UVC) light treatment with Tru-D^® UVC disinfection system and approval for room turnover. If ATP testing failed, the room was re-cleaned until it passed. For terminal cleaning of any isolation room, all supplies in the carts were discarded, carts thoroughly cleaned, and curtains changed.

Seven months after patient #1 was identified, due to the persistent outbreak, environmental samples were collected from the sinks and floor drains of all patient rooms and the procedure room in the BICU using an Eswab^TM. Cultures were incubated using ChromAgar^TM C. auris selective media. These areas were cultured because it was hypothesized that C. auris can persist in plumbing, similar to gram-negative rods. ^{Reference Lowe, Willey, O’Shaughnessy, Lee, Lum and Pike3} Due to limited resources, environmental cultures were restricted to these areas.