According to the CDC, 13 cases of Candida auris infection(www.cdc.gov) have been identified in the United States as of Nov. 4. The yeast, which has proven to be resistant to antifungal drugs, has affected only hospitalized patients to date.
This photo shows a strain of Candida auris cultured in a petri dish. The CDC has reported 13 cases of C. auris infection in the United States as of Nov. 4.
Seven of the cases occurred between May 2013 and August 2016 and are detailed in a Morbidity and Mortality Weekly Report(www.cdc.gov) (MMWR) first posted on Nov. 4. The remaining six cases were identified after the report published and are still under investigation.
The MMWR also provides a comprehensive overview of C. auris, some isolates of which worldwide have demonstrated resistance to all three major classes of antifungal drugs and are associated with a high mortality rate.
In June, the CDC issued a clinical alert to U.S. health care facilities(www.cdc.gov) describing the global emergence of C. auris and requesting that laboratories report cases and send samples to state and local health departments and the agency. Since then, the CDC has been working with several state and local health departments to investigate reports of C. auris infection.
- The CDC has identified 13 cases of Candida auris infection in the United States, detailing the first seven of them in a Morbidity and Mortality Weekly Report (MMWR).
- C. auris was first reported in 2009 after being isolated from external ear canal discharge of a patient in Japan; additional cases have since been reported in multiple countries.
- According to the MMWR, the infection has been seen in patients from four states: New York, Illinois, Maryland and New Jersey.
"We need to act now to better understand, contain and stop the spread of this drug-resistant fungus," said CDC Director Tom Frieden, M.D., M.P.H., in a Nov. 4 news release. "This is an emerging threat, and we need to protect vulnerable patients and others."
Background on Emerging Global Threat
C. auris was first described in 2009 after being isolated from external ear canal discharge of a patient in Japan. Additional cases, including reports of bloodstream infections, have since been seen in at least a dozen countries. Among them are Colombia, India, Israel, Kenya, Kuwait, Pakistan, South Africa, South Korea, Venezuela and the United Kingdom.
The seven U.S. cases described in the MMWR involved patients in four states: New York, Illinois, Maryland and New Jersey. All of these patients had serious underlying medical conditions and had been hospitalized an average of 18 days when C. auris was isolated. Four of the patients died; however, it's unclear whether the deaths were attributable to C. auris infection or to their underlying health conditions.
In two separate instances, two patients who had been treated in the same hospital or long-term care facility had nearly identical fungal strains. The first instance included two Illinois patients who were admitted to the same hospital on three separate occasions but were on different floors or wings of the hospital. These two patients were subsequently also admitted to a long-term acute-care hospital within days of one another, although their admission dates did not overlap.
The second instance involved patients in Maryland and New Jersey. The patient in Maryland was a resident of New Jersey and had been hospitalized at the same time as the New Jersey patient, in the same New Jersey hospital, but on a different ward. This overlapping admission occurred about six months before C. auris was identified in the Maryland hospital.
The CDC said these findings suggest that C. auris infection could be spread in health care settings.
Six of the seven cases were identified through retrospective review of hospital and reference laboratory records. Identifying C. auris requires specialized laboratory methods because it can easily be misidentified as another type of Candida infection -- as it was in most of the samples identified in the MMWR -- which can lead to ineffective treatment.
More than 70 percent of the C. auris strains from U.S. patients showed some drug resistance, making treatment more difficult. Although samples of C. auris strains from other countries were found to be resistant to the three major classes of antifungal medications, none of the U.S. strains reported on in the MMWR were resistant to all three.
Based on laboratory testing, the U.S. strains were found to be related to strains from South Asia and South America. But it should be noted that none of these patients travelled to or had any direct links to those regions and were most likely infected locally.
Recommendations for Health Care Professionals
The CDC recommends health care professionals in acute-care settings implement strict Standard and Contact Precautions(www.cdc.gov) to control the spread of C. auris.
"Facilities should conduct thorough daily and after-discharge cleaning of rooms of C. auris patients with an (Environmental Protection Agency)-registered disinfectant active against fungi," the release said. "Any cases of C. auris should be reported to the CDC and state and local health departments. The CDC can assist in identifying this particular type of Candida if needed."
The CDC's Antibiotic Resistance Laboratory Network is providing additional lab support in four regional laboratories to test fungal susceptibility of Candida species and identify emerging resistance. The agency also is expanding tracking of this fungus through the Emerging Infections Program. Information gathered through these networks will help track resistance patterns and inform policies and interventions.
"It appears that C. auris arrived in the United States only in the past few years," said Tom Chiller, M.D., M.P.H., chief of the CDC's Mycotic Diseases Branch, in the release. "We're working hard with partners to better understand this fungus and how it spreads so we can improve infection control recommendations and help protect people."
Related AAFP News Coverage
AAFP Joins CDC, Other Groups in Fighting Antibiotic Resistance
CDC: Candida auris(www.cdc.gov)