WASHINGTON — Enhanced surveillance measures helped to identify a silent outbreak of Candida auris in long-term care and skilled nursing facilities across southern California, a researcher said here, allowing these facilities to initiate containment efforts before clinical infections became widespread.
After C. auris was identified in several facilities, a county-wide point prevalence survey helped public health authorities find other outbreaks and implement infection control procedures, reported Ellora Karmarkar, MD, of the CDC, at a late-breaking IDWeek presentation.
In the end, among 165 patients found to be colonized with C. auris, only five developed candidemia or a clinical infection, she noted.
“Enhanced surveillance detected C. auris in the region three months before the first C. auris positive blood culture that would be identified by routine surveillance. This early detection allowed a substantial lead time for investigation and implementation of control measures,” Karmarkar told MedPage Today.
Karmarkar said that patients in long-term acute care facilities and ventilator skilled nursing facilities (vSNFs) commonly develop C. auris colonization. Typically, about 5%-10% of colonized patients develop invasive infections.
“These patients generally do not require acute intensive care, but have severe, complex medical conditions and ongoing medical needs,” she said, such as dialysis and ventilator care.
In the southern California outbreak she recounted here, C. auris was first identified through one long-term care patient’s urine specimen. Staff then performed “point prevalence surveys” (where skin swabs were collected from patients’ axilla and groin) that identified four other colonized patients. From there, they widened the search area to three affiliated vSNFs, all of which had colonized patients.
Then they took a “novel approach,” Karmarkar said — performing point-prevalence surveys at all three long-term acute care and all 14 vSNFs in Orange County. In addition, they sought to contain further spread and measure gaps in existing infection prevention — through assessing adherence to contact precautions, availability of hand sanitizer, hand hygiene practices, and environmental cleaning in colonized facilities.
“They were lucky,” Ghinwa Dumyati, MD, of the University of Rochester Medical Center in New York, who was not involved with the research, told MedPage Today. She explained how unusual it was to find C. auris in non-sterile samples, such as urine.
“For non-sterile samples, no one checks for it because it’s so common and it’s very labor intensive. I don’t think it’s something that’s doable across the U.S. because of the labor that’s involved. On blood these days, if you have a Candida, everyone pushes to make sure it’s not Candida auris.”
Karmarkar said the surveillance was made possible when a local clinical lab, at the behest of public health officials, began offering urine testing for C. auris.
Overall, Karmarkar and colleagues found C. auris in nine facilities total — all three long-term acute care facilities and six vSNFs. There were a total of 26 colonized patients in the long-term acute care facilities and 19 in the first six of 14 vSNFs surveyed. Whole-genome sequencing indicated a single introduction and local transmission, she reported.
“This is kind of amazing that they were able to detect it before they had a case. Most of the detection is when you have a case that’s sick and you identify it. In this case, no one was sick,” Dumyati said. “It’s usually a clinical case [and] it’s usually blood. This is an unusual case because it started by detection de novo in the area of a colonized patient.”
Karmarkar and colleagues surveyed adherence to hand hygiene procedures, and found they were below 50% in five facilities; adherence scores ranged from 22% to 86% across all facilities. Environmental cleaning assessments painted a similar picture.
“Many facilities [had] inadequate technique, use of ineffective cleaning products, inconsistent cleaning of mobile medical equipment, and disagreement between staff members on who was responsible for cleaning computers, hospital carts, and bed alarms,” Karmarkar said.
Subsequently, infection prevention teams recommended increased access to alcohol-based hand rub, as well as regular audits of hand hygiene and environmental cleaning, Karmarkar noted.
A total of 165 colonized patients were identified at nine of 17 facilities by September 2019. Karmarkar said that one long-term acute care facility and one vSNF has ongoing transmission. She noted this was likely due to “a high burden of colonization at initial assessment, and gaps in infection prevention.”
“High-risk facilities should strongly consider implementing enhanced laboratory surveillance for C. auris, and ensure consistent and rigorous adherence to infection prevention measures, in particular, hand hygiene and thorough cleaning of the environment and mobile medical equipment with an appropriate disinfectant,” Karmarkar told MedPage Today after her presentation.
Dumyati said that having a rapid diagnostic test would make detection in urine more feasible.
“If we had an easy test we could do on urine that would be good, but we don’t have a quick test that will tell you that. You know it’s a Candida, but you don’t know the species and that’s what takes the time.”