Field Performance of Mass PCR Screening and Targeted Treatment in an Amazonian Low Malaria Transmission Setting

Abstract The three main obstacles to the elimination of malaria in French Guiana are asymptomatic carriers of Plasmodium vivax, relapses and, to a lesser extent, Plasmodium falciparum. This study aims to assess the impact of PCR-based mass screening and treatment (MSAT) interventions in this malaria-endemic area.Two MSAT interventions were conducted twelve months apart in inhabitants of Saint Georges de l’Oyapock village, which has the highest malaria burden in French Guiana. Symptomatic malaria incidence was also passively monitored through the local health center from 12 months before the first intervention until the end of the second intervention.At the time of the first intervention, malaria prevalence was 6.7% [CI95 5.4-7.9%], including 90% of Plasmodium vivax cases and 10% Plasmodium falciparum (n=1,501 participants). Twelve months later, it had decreased by 53.7% to a value of 2.5% [CI95 2.0-3.9%] (p<0.05; n=1,271 inhabitants), of which 83% and 17% of cases showed Plasmodium vivax and Plasmodium falciparum carriage, respectively. Similarly, the passive malaria detection carried out by the health center during the 12-month surveillance period that followed the first MSAT noted a decrease in symptomatic Plasmodium spp..This study suggests that the implementation of mass PCR testing and the subsequent malaria treatment of positive cases could reduce the prevalence of both symptomatic and asymptomatic malaria infections in the Amazonian context.