CDC warns of rising Cladophialophora bantiana brain fungus cases in the US

The Centers for Disease Control and Prevention (CDC) has issued a warning regarding a significant increase in cases of Cladophialophora bantiana, a rare and potentially lethal black brain fungus, in the United States.

Data from a University of Washington laboratory indicates that detection rates have risen sharply. While annual cases typically ranged from one to five between 2009 and 2023, the number rose to eight in 2024 and reached 14 confirmed infections in 2025. This represents a nearly fourfold increase in recent years.

Cladophialophora bantiana is a neurotropic fungus that can enter the body through inhalation and travel to the brain, often causing severe abscesses. The infection is highly dangerous, with mortality rates estimated between 60 and 70 percent.

Health officials note that diagnosis remains a challenge because standard rapid tests can sometimes overlook this specific pathogen. Consequently, the CDC is calling for a systematic, nationwide reporting and tracking system to better monitor the trend, though the exact cause of the increase remains unknown.