U.S. detections of Cladophialophora bantiana, a dangerous fungus that most often targets the central nervous system (CNS), rose fourfold from 2023 to 2025. CIDRAP has the news.
The study analyzed all cases of C bantiana identified through PCR testing at University of Washington’s (UW) lab from January 2009 to July 2026. The fungus is highly virulent and carries a 60% to 70% case fatality rate, even with aggressive treatment. Half of infected patients don’t have weakened immune systems. The route of infection is thought to be inhalation or infection of a skin lesion, followed by spread to the brain, where it causes an abscess. The risk factors and epidemiology of the fungus are not understood.
The fungus has only rarely been isolated from environmental sources. National surveillance for it also doesn’t exist.
Fungal PCR identified 48 confirmed infections and one probable case from 2009 to 2026, so the infection is rare. Of the 49 cases, 88% were found in brain tissue, and 12% were detected in the lung. No CNS infections were found outside of the brain. One to five cases were identified from 2009 to 2023 in each year, rising to eight in 2024 and 14 in 2025. From 2017 to 2023, 8.4 cases were detected per 1,000 CNS samples on average; by 2025, however, infections spiked to 26 per 1,000, representing a 210% increase.
The authors urged clinicians to be aware of the rising incidence of C bantiana in patients with signs and symptoms of a brain abscess.
