Multidrug-Resistant Aspergillus fumigatus Carrying Mutations Linked to Environmental Fungicide Exposure - Three States, 2010-2017.

The environmental mold Aspergillus fumigatus is the primary cause of invasive aspergillosis. In patients with high-risk conditions, including stem cell and organ transplant recipients, mortality exceeds 50%. Triazole antifungals have greatly improved survival (1); however, triazole-resistant A. fumigatus infections are increasingly reported worldwide and are associated with increased treatment failure and mortality (2). Of particular concern are resistant A. fumigatus isolates carrying either TR34/L98H or TR46/Y121F/T289A genetic resistance markers, which have been associated with environmental triazole fungicide use rather than previous patient exposure to antifungals (3,4). Reports of these triazole-resistant A. fumigatus strains have become common in Europe (2,3), but U.S. reports are limited (5). Because of the risk posed to immunocompromised patients, understanding the prevalence of such isolates in patients is important to guide clinical and public health decision-making. In 2011, CDC initiated passive laboratory monitoring for U.S. triazole-resistant A. fumigatus isolates through outreach to clinical laboratories. This system identified five TR34/L98H isolates collected from 2016 to 2017 (6), in addition to two other U.S. isolates collected in 2010 and 2014 and reported in 2015 (5). Four of these seven isolates were reported from Pennsylvania, two from Virginia, and one from California. Three isolates were collected from patients with invasive pulmonary aspergillosis, and four patients had no known previous triazole exposure. A. fumigatus resistant to all triazole medications is emerging in the United States, and clinicians and public health personnel need to be aware that resistant infections are possible even in patients not previously exposed to these medications.

Investigation of a Candida auris outbreak in a skilled nursing facility - Virginia, United States, October 2020-June 2021.

Candida auris, an emerging multi-drug resistant organism, is an urgent public health threat. We report on a C. auris outbreak investigation at a Virginia ventilator skilled nursing facility. During October 2020-June 2021, we identified 28 cases among residents in the ventilator unit. Genomic evidence suggested ≥2 distinct C. auris introductions to the facility. We identified multiple infection and prevention control challenges, highlighting the importance of strengthening multi-drug resistant organism prevention efforts at ventilator skilled nursing facilities.