Sensitivity of P. vivax rapid antigen detection tests and possible implications for self-diagnostic use.

In a prospective study amongst febrile travellers returning from malaria-endemic areas to Berlin, Germany, two rapid malarial antigen detection tests were compared for the diagnosis of vivax malaria with routine microscopy. With ICT Malaria P.f./P.v.((R)), 664 samples of 492 patients were examined. 17 patients had vivax malaria, out of which 11 infections were missed (35.3% sensitivity). With OptiMal((R)), 659 samples of 539 patients were examined. 22 patients had vivax malaria, and all infections were identified correctly (100% sensitivity). Specificity was 100% with both tests. The ICT Malaria P.f./P.v.((R)) is advertised for layman use during travel, and the literature was reviewed with respect to the question of suitability of these devices for self-testing. It is concluded that with the ICT Malaria P.f./P.v.((R)), the detection of non-falciparum (i.e. predominantly vivax) malaria is unreliable, and test interpretation for medically untrained individuals particularly in distress might be too complicated even after proper instruction.