Evaluation of the effectiveness of the OptiMAL-IT™ rapid test in the follow up of patients diagnosed with malaria in the Peruvian Amazon

Introduction: In Peru, optical microscopy with the thick smear test continues to be performed for the follow-up of malaria patients. This test is simple but it requires microscopic equipment and suitable staff to perform the reading of the samples. Studies suggest that the rapid OptiMAL-IT™ test is an option for follow-up. Objective: To evaluate the effectiveness of OptiMAL-IT™ as a follow-up test in malaria patients in endemic areas of Perú. Materials and methods: We conducted an observational, analytical cross-sectional study of diagnostic tests performed in patients with malaria. We selected all the patients attending different health facilities in the Peruvian departments of San Martín and Loreto who met the inclusion criteria. Optical microscopy with thick smear and OptiMAL-IT™ was used on days 2, 3, 7, and 14 for Plasmodium vivax and until day 21 of follow-up for Plasmodium falciparum. Percentages of correctly classified samples and predictive values were calculated, and the results were compared between the western jungle and the eastern jungle using Chi2 or Fisher’s exact tests. Results: We registered 262 patients from San Martín and 302 from Loreto. The percentage of correctly classified cases and the negative predictive value were higher than 92.0% and 93,0%, respectively, from the third day of follow-up; no statistical differences were found in the results obtained from the western jungle and those from the eastern jungle. Conclusions: The OptiMAL-IT™ test would be effective as a follow-up test in patients diagnosed with malaria in endemic areas of Perú.