Deadly fungal brain infections spike fourfold since 2023, CDC study finds

Cases of the rare and deadly fungal brain infection Cladophialophora bantiana are rising sharply, with a fourfold increase since 2023, according to a new CDC-affiliated study. Scientists do not know how the fungus is contracted or why cases are spiking. Researchers from the University of Washington and the CDC analyzed laboratory data, finding 48 confirmed cases across 21 states and Washington, DC, between 2009 and 2026. Annual cases jumped from one to five before 2023 to eight in 2024 and 14 in 2025. The infection has a 60-70% mortality rate and can affect healthy individuals. C. bantiana primarily targets the brain, forming pus-filled pockets, unlike most fungal infections that spread from elsewhere in the body. First identified in 1911, its natural habitat and infection route remain unknown, though experts suspect skin entry or inhalation. Researchers emphasize the need for systematic data collection to understand the rise.