Global perspective on gaps in fungal diagnostics in low-resource settings: WHO landscape analysis and research priorities for invasive fungal diseases

Invasive fungal diseases (IFDs) are a growing global health threat, particularly in low-income and middle-income countries (LMICs), where diagnostic capacity is limited. The emergence and spread of antifungal resistance further complicate clinical management. Despite the high burden of IFDs, diagnostic development for fungal pathogens has lagged compared with that for its bacterial and viral counterparts. In this Review, we synthesised findings from WHO's 2024 diagnostic landscape analysis of fungal priority pathogens. We discussed the availability, accessibility, and performance of the current diagnostic tools, including phenotypic, immunological, and molecular methods, and identified key gaps in LMICs. WHO's research and development priorities for diagnostics for LMICs are also presented herein. The assessment reveals that most diagnostic platforms for IFDs are culture dependent, infrastructure intensive, and inaccessible at primary and secondary health-care levels in LMICs. Non-culture-based methods, such as lateral flow immunoassays and molecular diagnostics, are promising, but remain restricted in scope, species coverage, and affordability. Multiplex platforms capable of simultaneous broad pathogen detection and antifungal resistance testing are scarce. WHO has identified priority areas for diagnostic innovation, including simplified lateral flow immunoassays, automated culture systems, and integrated molecular platforms suitable for use in LMICs. Addressing diagnostic gaps for IFDs requires targeted investment in simplified, rapid, and affordable diagnostic tools that can be deployed across multiple levels of health-care system. WHO's research and development priorities aim to guide diagnostic developers and public health stakeholders in accelerating innovation and improving access to fungal diagnostics, particularly in LMICs, to reduce IFD-related morbidity and mortality.