Plasmodium falciparum Parasites With Histidine-Rich Protein 2 (pfhrp2) and pfhrp3 Gene Deletions in Frontier Endemic Regions of Brazilian Amazon.

Studies reporting deletions of the pfhrp2 and pfhrp3 genes in P. falciparum populations in various malaria-endemic countries, including countries bordering Brazil, are increasing. Individuals infected with P. falciparum carrying deletions of the pfhrp2/3 genes may yield false-negative results in Rapid Diagnostic Tests (RDTs) based on the detection of these antigens. A total of 342 samples from symptomatic individuals infected with P. falciparum, collected during epidemiological surveillance activities in the municipalities of the international frontier between Brazil and Peru and between Brazil and Venezuela were analysed. Of the 342 samples evaluated, 86 (25.2%) showed pfhrp2-deletion, 32 (9.4%) double deletions of the pfhrp2/3 genes, and 168 (49.1%) had a single deletion of the pfhrp3 gene. The frequency of parasites with pfhrp2/3 deletions highlights the importance of genomic surveillance in international border areas, alongside the evaluation of the effectiveness of RDTs used in the country.