The use of a dipstick antigen-capture assay for the diagnosis of Plasmodium falciparum infection in a remote forested area of central India.

Abstract

A study was carried out in a highly malarious forested belt of central India (Madhya Pradesh) to evaluate the usefulness of a dipstick antigen-capture assay (ParaSight F) as a diagnostic method for Plasmodium falciparum appropriate for field use. In all, 1,231 patients with fever were screened in parallel with the taking of thick blood smears. The sensitivity and specificity of the dipstick test for detection of P. falciparum were 93% and 92.5%, respectively. Results also indicate that the dipstick test result became negative within seven days after initiation of curative chemotherapy in the majority of cases (95%). Tribal populations in remote forested areas are important reservoirs of P. falciparum that are mostly resistant to standard antimalarial drugs and a source of malaria to the rest of the country. Control of malaria is limited by inaccessibility, lack of medical services, public ignorance of the disease, and other technical problems. In this population, the dipstick assay was found to be highly accurate, simple, and rapid, suggesting that it may be used in remote forested areas without the need for microscopic examination. The simplicity of the dipstick test enabled administration of more effective and expensive antimalarials preventing further buildup and dissemination of resistant parasites and a return of symptoms.