RDTs are fast, but they can't count parasites or confirm species. Here is when a field-ready microscope still earns its place in the kit.
The rapid diagnostic test won the field on speed and simplicity, and for good reason — it triages malaria at a scale microscopy never could. But speed buys breadth, not depth, and there are clinical questions an RDT structurally cannot answer.
Microscopy earns its place at three points: parasite density (to grade severity and monitor treatment response), species confirmation beyond the RDT’s antigen targets, and the tiebreaker for a convincing case that the RDT misses — the HRP2-deletion scenario among them. A field-ready microscope is the depth layer behind the RDT’s breadth. For the full specification, see our guide to field-ready microscopes.
The decision is not microscopy-or-RDT; it is microscopy-and-RDT, layered. The RDT screens; the slide adjudicates the cases that matter most. A program that stocks only the fast test has a detection ceiling it cannot see past.
International Health Journal designs the diagnostic kit as a two-tier system precisely so the field is never forced to choose between speed and the answer.