Auris Transmission Research Articles

Surveillance diagnostic algorithm using real-time PCR assay and strain typing method development to assist with the control of C. auris amid COVID-19 pandemic

Candida auris continues to be a global threat for infection and transmission in hospitals and long-term care facilities. The emergence of SARS-CoV-2 has rerouted attention and resources away from this silent pandemic to the frontlines of the ongoing COVID-19 disease. Cases of C. auris continue to rise, and clinical laboratories need a contingency plan to prevent a possible outbreak amid the COVID-19 pandemic. Here, we introduce a two-tier Candida auris surveillance program that includes, first, a rapid qualitative rt-PCR for the identification of high-risk patients and, second, a method to analyze the isolated C. auris for strain typing using the Fourier-Transform Infrared spectroscopy. We have performed this two-tier surveillance for over 700 at-risk patients being admitted into our hospital and have identified 28 positive specimens (4%) over a 1-year period. Strain typing analysis by the IR spectrum acquisition typing method, supplemented by whole genome sequencing, has shown grouping of two significant clusters. The majority of our isolates belong to circulating African lineage associated with C. auris Clade III and an isolated strain grouping differently belonging to South Asian lineage C. auris Clade I. Low numbers of genomic variation point to local and ongoing transmission within the Los Angeles area not specifically within the hospital setting. Collectively, clinical laboratories having the ability to rapidly screen high-risk patients for C. auris and to participate in outbreak investigations by offering strain typing will greatly assist in the control of C. auris transmission within the hospital setting.

Integrated genomic, epidemiologic investigation of Candida auris skin colonization in a skilled nursing facility.

Candida auris is a fungal pathogen of high concern due to its ability to cause healthcare-associated infections and outbreaks, its resistance to antimicrobials and disinfectants and its persistence on human skin and in the inanimate environment. To inform surveillance and future mitigation strategies, we defined the extent of skin colonization and explored the microbiome associated with C. auris colonization. We collected swab specimens and clinical data at three times points between January and April 2019 from 57 residents (up to ten body sites each) of a ventilator-capable skilled nursing facility with endemic C. auris and routine chlorhexidine gluconate (CHG) bathing. Integrating microbial-genomic and epidemiologic data revealed occult C. auris colonization of multiple body sites not targeted commonly for screening. High concentrations of CHG were associated with suppression of C. auris growth but not with deleterious perturbation of commensal microbes. Modeling human mycobiome dynamics provided insight into underlying alterations to the skin fungal community as a possible modifiable risk factor for acquisition and persistence of C. auris. Failure to detect the extensive, disparate niches of C. auris colonization may reduce the effectiveness of infection-prevention measures that target colonized residents, highlighting the importance of universal strategies to reduce C. auris transmission.

Repeated Prevalence Surveys and Admission Screening for Candida auris at One Long-Term Acute-Care Hospital, Chicago, 2016–2019

Background: Since the initial identification of Candida auris in 2016 in Chicago, ongoing spread has been documented in the Chicago area, primarily among older adults with complex medical issues admitted to high-acuity long-term care facilities, including long-term acute-care hospitals (LTACHs). As of October 2019, 790 cases have been reported in Illinois. Knowing C. auris colonization status on admission is important for prompt implementation of infection control precautions. We describe periodic facility point-prevalence surveys (PPSs) and admission screening at LTACH A. Methods: Beginning September 2016, we conducted repeated PPSs for C. auris colonization at LTACH A. After a baseline PPS, we initiated admission screening in May 2019 for patients without prior evidence of C. auris colonization or infection. C. auris screening specimens consisted of composite bilateral axillary/inguinal swabs tested at public health laboratories. We compared a limited set of patient characteristics based on admission screening results. Results: From September 2016 through October 2019, 277 unique patients were screened at LTACH A during 10 PPSs. Overall, 36 patients (13%) were identified to be colonized. The median facility C. auris prevalence increased from 2.8% in 2016 to 37% in 2019 (Fig. 1). During May–September 2019, among 174 unique patients admitted, 151 (87%) were screened for C. auris colonization on admission, of whom 18 (12%) were found to be colonized. Overall, 14 patients were known to have C. auris colonization on admission and were not rescreened, and 9 patients were discharged before screening specimens could be collected. A significantly higher proportion of patients testing positive for C. auris on admission had a central venous catheter or a peripherally inserted central catheter or were already on contact precautions (Table 1). The PPS conducted on October 1, 2019, revealed 5 new C. auris colonized patients who had screened negative on admission. Conclusions: Repeated PPSs at LTACH A indicated control of C. auris transmission in 2016–2017, followed by increasing prevalence beginning in May 2018, likely from patients admitted with unrecognized C. auris colonization and subsequent facility spread. Admission screening allowed for early detection of C. auris colonization. However, identification during subsequent PPS of additional colonized patients indicates that facility transmission is ongoing. Both admission screening and periodic PPSs are needed for timely detection of colonized patients. Given the high C. auris prevalence in LTACHs and challenges in identifying readily apparent differences between C. auris positive and negative patients on admission, we recommend that all patients being admitted to an LTACH in endemic areas should be screened for C. auris.Funding: NoneDisclosures: None

Implementing Admission Screening for Candida auris

Background:Candida auris is a globally emerging, multidrug-resistant fungal pathogen that causes serious, difficult-to-treat infections in hospitalized patients. C. auris cases in the United States have been linked to receipt of healthcare overseas. Outbreaks have also occurred in New York City, New Jersey, Chicago, and most recently in California. We provide care to patients from all 50 states and 138 countries; therefore, we are at risk for encountering C. auris in our facility. Setting: An academic, tertiary-care center with 1,297 licensed beds and >62,000 admissions each year. Methods: Infection prevention and control (IPAC) initiated a C. auris screening program in August 2019 in partnership with the State Health Department. A case-finding tool was created to identify adult patients admitted in the previous 24 hours from countries and areas of the United States (Chicago, New Jersey, and New York metropolitan areas) with known C. auris transmission based on the zip code of their primary address. IPAC sends an electronic communication via the electronic medical record (EMR) alerting the patient care team that the patient meets criteria for screening along with information on C. auris and links to a tool kit with additional resources to help answer questions. After obtaining verbal consent, the patient’s primary nurse collects a composite axilla–groin skin swab using a nylon-flocked swab (BD ESwab collection and transport system; Becton Dickinson, Sparks, MD). The sample is sent to the State Health Department laboratory for testing by polymerase chain reaction (PCR). Results are communicated back to IPAC and then scanned into the patient’s EMR. Results: From August 2019 to November 2019, 157 patients were identified for C. auris screening using the case-finding tool. Testing was performed on 95 patients; all tests were negative. The primary reasons for testing not to be performed on eligible patients were inability to obtain verbal consent and patient dismissal before sample could be obtained. The need for a special swab that is not routinely stocked on patient care units has been a limitation to timely specimen collection. Conclusions: The EMR can be leveraged for early identification and screening of patients at risk of C. auris colonization. Case finding tools can be effectively replicated and modified to respond to emerging infections and changing surveillance guidelines.Funding: NoneDisclosures: None

897. Prevalence of Candida auris at Body Sites, Characterization of Skin Microbiota, and Relation of Chlorhexidine Gluconate (CHG) Skin Concentration to C. auris Detection Among Patients at a High-Prevalence Ventilator-Capable Skilled Nursing Facility (vSNF) with Established CHG Bathing

BackgroundvSNF patients are at high risk of colonization and infection with C. auris. CHG bathing has been used as an intervention to reduce nosocomial transmission of multi-drug-resistant organisms, but its effect on C. auris is unclear.MethodsWe studied a 70-bed ventilator ward in a 300-bed vSNF in Chicago, IL with a high prevalence of C. auris and established CHG bathing. Swab samples were collected from patients for culture, microbiome analysis, and CHG skin concentration testing (Table 1).ResultsWe collected 2,467 samples (950 culture, 950 microbiome, 567 CHG) from 57 patients during 2 surveys conducted January–March 2019. Forty-six (81%) patients had C. auris cultured from ≥1 body site. Mean (±SD) age was 59 (±14) years, 40% were women, 70% were African American, mean (±SD) Charlson score was 3 (±2). Patients colonized with C. auris were more likely to be mechanically ventilated (50% vs. 0%, P < 0.001), have a gastrostomy tube (78% vs. 27%, P < 0.001) or have urinary catheter (72% vs. 23%, P = 0.01) than noncolonized patients. Frequency of C. auris isolation varied among 10 body sites tested (P < 0.001); colonization of anterior nares (41%) and hands (40%) was detected most often (Figure 1). By ITS1 analysis, all isolates were members of the C. auris South American clade. Skin microbiome sequencing confirmed culture Results. While Malassezia is the dominant genera observed in healthy volunteers and patients in this vSNF, C. auris was observed to dominate the fungal community of multiple skin sites, including nares, hands, inguinal, toe web (Figure 2). Other Candida spp. were also identified on the skin of patients in the current study, but at lower relative abundance. CHG was detected on skin of 52 (91%) patients (median CHG concentration 19.5 µg/mL; IQR 4.9–78.1 µg/mL). In a mixed-effects model controlling for body site and multiple measurements per patient, odds of C. auris detection by culture were less at CHG concentrations ≥625 µg/mL than at lower concentrations (Figure 3; OR 0.25, 95% CI: 0.10–0.66; P = 0.005).ConclusionFrequent C. auris colonization of vSNF patients’ anterior nares and hands suggests that nasal decolonization and patient hand hygiene are potential options to reduce C. auris transmission. High concentrations of CHG may be needed to suppress C. auris on skin. Disclosures All Authors: No reported Disclosures.

LB1. Regional Assessment and Containment of Candida auris Transmission in Post-Acute Care Settings—Orange County, California, 2019

BackgroundPatients in long-term acute care hospitals (LTACHs) and skilled nursing facilities with ventilator units (VSNFs) are at high risk for Candida auris colonization; among patients colonized with this emerging pathogen, 5%–10% develop invasive disease with >45% mortality. In September 2018, a California LTACH-affiliated laboratory began enhanced C. auris surveillance by classifying species of Candida isolated from routine urine specimens. In February 2019, the first known Southern California case was detected in an Orange County (OC) LTACH; the patient had not traveled outside the region, indicating local acquisition. We performed point prevalence surveys (PPS) and infection prevention (IP) assessments at all OC LTACHs and VSNF subacute units to identify patients colonized with C. auris and control transmission.MethodsDuring March–August 2019, we conducted PPS at facilities by collecting composite axilla and groin swabs for C. auris polymerase chain reaction testing and reflex culture from all patients who assented. Facilities with ≥1 C. auris-colonized patient repeated a PPS every 2 weeks to assess for new transmission. Isolate relatedness was assessed by whole-genome sequencing (WGS). We evaluated hand hygiene (HH) adherence, access to alcohol-based hand rubs (ABHR), and cleaning of high-touch surfaces to guide IP recommendations.ResultsThe first PPS at all OC LTACHs (n = 3) and adult VSNFs (n = 14) identified 45 C. auris-colonized patients in 3 (100%) LTACHs and 6 (43%) VSNFs; after repeated PPS, the total count reached 124. Most patients (70%) were at 2 facilities (Table 1). Three of 124 patients developed candidemia. To date, isolates from 48 patients have completed WGS; all were highly related (<11 single-nucleotide polymorphisms) in the African clade. Of 9 facilities with C. auris, 5 had HH adherence < 50%, 3 had limited ABHR, and at 2, <60% of assessed high-touch surfaces were clean. We recommended regular HH and cleaning audits, and increased ABHR.ConclusionOur investigation, prompted by enhanced surveillance, identified C. auris at 9 OC facilities. WGS indicated a single introduction and local transmission. Early detection, followed by rapid county-wide investigation and IP support, enabled containment efforts for C. auris in OC. Disclosures All authors: No reported disclosures.

Identification of Drug Resistant Candida auris.

Candida auris is a multidrug resistant yeast, recognized as a cause of invasive infections and health care associated outbreaks around the world. C. auris is of great public health concern, due to its propensity for drug resistance, mode and pace of its transmission, and the possibility that biologic and epidemiologic factors could exacerbate worldwide emergence of C. auris infections. Currently, outbreak response is complicated by limited treatment options and inadequate disinfection strategies, as well as by issues (misidentification, long turnaround time) associated with application of commonly used diagnostic tools. Misdiagnosis of C. auris is common since many diagnostic platforms available in clinical and public health laboratories depend on reference databases that have not fully incorporated C. auris. Moreover, the correlation between minimal inhibitory concentration values (MICs) and clinical outcomes is poorly understood resulting in the absence of C. auris-specific breakpoints. New, accurate and fast diagnostic methods have emerged to facilitate effective patient management and improve infection control measures, ultimately reducing the potential for C. auris transmission. This review provides an overview of available C. auris detection/identification and antifungal susceptibility determination methods and discusses their advantages and limitations. A special emphasis has been placed on culture-independent methods that have recently been developed and offer faster turnaround times.

Candida auris: What Have We Learned About Its Mechanisms of Pathogenicity?

Candida auris has emerged globally as a multidrug-resistant (MDR) medical care-associated fungal pathogen. Recent reports have demonstrated that C. auris usually expresses fewer virulence factors than does Candida albicans. However, the tendency of C. auris transmission within and between healthcare facilities is unique among Candida spp. and is possibly promoted by virulence and pathogenicity factors that facilitate skin colonization and environmental persistence. To understand the ability of this yeast to cause disease, we herein discuss several virulence and pathogenicity aspects of C. auris.

161. Prevalence and Risk Factors for Candida auris Colonization Among Patients in a Long-term Acute Care Hospital—New Jersey, 2017

Background Candida auris can be transmitted in healthcare settings, and patients can become asymptomatically colonized, increasing risk for invasive infection and transmission. We investigated an ongoing C. auris outbreak at a 30-bed long-term acute care hospital to identify colonization for C. auris prevalence and risk factors.MethodsDuring February–June 2017, we conducted point prevalence surveys every 2 weeks among admitted patients. We abstracted clinical information from medical records and collected axillary and groin swabs. Swabs were tested for C. auris. Data were analyzed to identify risk factors for colonization with C. auris by evaluating differences between colonized and noncolonized patients.ResultsAll 101 hospitalized patients were surveyed, and 33 (33%) were colonized with C. auris. Prevalence of colonization ranged from 8% to 38%; incidence ranged from 5% to 20% (figure). Among colonized patients with available data, 19/27 (70%) had a tracheostomy, 20/31 (65%) had gastrostomy tubes, 24/33 (73%) ventilator use, and 12/27 (44%) had hemodialysis. Also, 31/33 (94%) had antibiotics and 13/33 (34%) antifungals during hospitalization. BMI for colonized patients (mean = 30.3, standard deviation (SD) = 10) was higher than for noncolonized patients (mean = 26.5, SD = 7.9); t = −2.1; P = 0.04). Odds of colonization were higher among Black patients (33%) vs. White patients (16%) (odds ratio [OR] 3.5; 95% confidence interval [CI] 1.3–9.8), and those colonized with other multidrug-resistant organism (MDRO) (72%) vs. noncolonized (44%) (OR 3.2; CI 1.3–8.0). Odds of death were higher among colonized patients (OR 4.6; CI 1.6—13.6).Figure 1:Incidence and prevalence of Candida auris colonization by point prevalence survey (PPS), at a long-term acute care hospital, New Jersey, February 28 and June 14, 2017 (N = 101).ConclusionPatients in long-term acute care facilities and having high prevalences of MDROs might be at risk for C. auris. Such patients with these risk factors could be targeted for enhanced surveillance to facilitate early detection of C. auris. Infection control measures to reduce MDROs’ spread, including hand hygiene, contact precautions, and judicious use of antimicrobials, could prevent further C. auris transmission.AcknowledgementsThe authors thank Janet Glowicz and Kathleen Ross.Disclosures All authors: No reported disclosures.

Something wicked this way comes: What health care providers need to know about Candida auris.

Candida auris is a fungal pathogen that recently emerged and rapidly spread around the globe. It is now in Canada. C. auris can cause invasive disease with high mortality rates, is frequently resistant to one or more classes of antifungals, and can be difficult to identify in some clinical microbiology laboratories. C. auris can also involve prolonged colonization of patients' skin and contamination of surrounding environments, resulting in nosocomial outbreaks in hospitals and long-term care facilities. Clinicians, infection prevention and control practitioners and public health officials should be aware of how to mitigate the threat posed by this pathogen. Index cases of C. auris should be suspected in patients with invasive candidiasis and recent hospitalization in global regions where C. auris is prevalent, as well as in patients who fail to respond to empiric antifungal therapy and from whom unidentified or unusual Candida species have been isolated. If a case of C. auris infection or colonization is identified or suspected, the following should take place: notification of local public health authorities and infection prevention and control practitioners; placement of colonized or infected patients in single rooms with routine contact precautions; daily and terminal environmental disinfection with a sporicidal agent; contact tracing and screening for C. auris transmission; and referral of suspicious or confirmed isolates to provincial laboratories. Patients with symptomatic disease should be treated with an echinocandin pending the results of antifungal susceptibility testing, preferably in consultation with an infectious disease specialist. Through the vigilance of front-line health care workers and microbiologists, robust infection prevention and control practices, and local and national surveillance efforts, C. auris can be detected quickly, infections managed and transmissions prevented to protect patients in our health care system.