Evaluation of the Effect of Supervised Antimalarial Treatment on P. Vivax Malaria Recurrences

Abstract BackgroundRelapses in vivax malaria have posed great challenges to malaria control, accounting for a great proportion of reported cases. Knowing the real effectiveness of 7 day primaquine (PQ) scheme is crucial to understand not only the cost-effectiveness of implementing new anti-hypnozoite drugs but how health education strategies can guarantee better compliance and be reinforced. This study aimed the evaluation of the daily supervised treatment effect with chloroquine and PQ (in consented patients) versus prescription without supervision (non-consented patients), and the outcome was the passive detection of new positive thick blood smears until 180 days, based on the official data records from the National Malaria Control Program. The recurrences seen in the real life were therefore used as a surrogate for true relapses. Patients under supervised treatment had a lower risk of recurrence until day 180 when compared to the unsupervised treatment (17.9% vs 36.1%; p=0.027). The lack of consent in the non-supervised group (which followed standard of care in the real life) enabled proper comparison, as consent itself could lead to better compliance in this group. Future studies should scale such analysis to different settings in the Brazilian Amazon.