Which assay format is least likely to be used for rapid fungal serology testing due to limited ease of use?

• A. Lateral Flow Assays
• B. ELISA Assays
• C. Radial Immunodiffusion Assays
• D. Indirect Immunofluorescence Assays

Answer: (C)

For rapid fungal serology, you want formats that yield quick results with minimal hands-on time and simple equipment. Lateral flow assays fit this well, giving fast, point-of-care results. ELISA is also common in laboratories and can be streamlined for relatively quick turnaround. Indirect immunofluorescence can provide specific detection too, but it requires a fluorescence microscope and more skilled interpretation, which adds time and complexity. Radial immunodiffusion, however, relies on diffusion in an agar gel and needs long incubation and manual reading of precipitation rings, making it slow and cumbersome for rapid testing. That makes radial immunodiffusion the least suitable choice for rapid fungal serology due to limited ease of use.