Detection of Plasmodium spp. in asymptomatic blood donors by the new Brazilian NAT PLUS HIV/HBV/HCV/Malaria Bio-Manguinhos kit.

BACKGROUND: Transfusion-transmitted malaria (TTM) is a public health problem in endemic and nonendemic areas. The Brazilian Ministry of Health (MH) requested the development of a nucleic acid amplification test (NAT) for the detection of Plasmodium spp. in public blood centers to increase blood safety. STUDY DESIGN AND METHODS: The new Brazilian NAT kit named NAT PLUS HIV/HBV/HCV/Malaria Bio-Manguinhos was first implemented in HEMORIO, a public blood center in the city of Rio de Janeiro. Since October 1, 2022, this blood center has been testing all its blood donations for malaria in a pool of six plasma samples to detect Plasmodium spp. by real-time polymerase chain reaction (PCR). RESULTS: Since the implementation of the NAT PLUS platform until February 2023, HEMORIO has successfully received and tested 200,277 donations. The platform detected two asymptomatic donors in the city of Rio de Janeiro, which is a nonendemic region for malaria. Our analyses suggested a malaria from the Amazon region caused by Plasmodium vivax, in the first case, while an autochthonous transmission case by Plasmodium malariae was identified in the rural area of Rio de Janeiro state. DISCUSSION: The NAT PLUS platform detects Plasmodium spp. in plasma samples with sensitivity capable of detecting subpatent infections. This is the first time worldwide that a group developed and implemented molecular diagnosis for Plasmodium spp. to be used by public blood centers to avoid TTM.

Genotypic analysis of the gp41 HR1 region from HIV-1 isolates from enfuvirtide-treated and untreated patients.

OBJECTIVE: To evaluate the polymorphisms and resistance mutations in gp41 HR1 region of HIV-1. METHODS: The study included 28 HIV-positive patients undergoing enfuvirtide (ENF) treatment or not from Porto Alegre, Rio Grande do Sul state, and Rio de Janeiro, Rio de Janeiro state, between 2006 and 2009. Resistance mutations and polymorphisms of the gp41 HR1 region were detected using the genomic DNA of 12 ENF-untreated patients and 16 patients in ENF treatment, encompassing subtypes B, C, and F1. Sample subtypes were determined by neighbor-joining phylogenetic analysis with a Kimura's two-parameter correction. RESULTS: A high prevalence of polymorphisms unrelated to resistance was observed. Among ENF-untreated patients, 16% showed mutations related with resistance. Among patients in ENF treatment, 50% had resistance-related mutations. Overall, 17% of all isolates showed the N42S polymorphism related to ENF hypersusceptibility. The presence of ENF resistance mutations in the group of treated patients reduced viral load. The V38A substitution was the most frequent among treatment-experienced patients followed by the G36D/E, N42D, and V38M substitutions. CONCLUSIONS: The V38A substitution in the gp41 HR region was the most common resistance mutation among ENF-treated patients and was associated with increased viral load.