Surveillance of pfhrp2 and pfhrp3 gene deletions among symptomatic Plasmodium falciparum malaria patients in Central Vietnam

Malaria Journal

Research

Dang Viet Dung¹  Ngo Duc Thang¹  Tran Thanh Duong¹  Nguyen Thi Hong Ngoc¹  Nguyen Thi Huong Binh¹  Kimberly A. Edgel²  Nicholas J. Martin²  Tran Khanh Long³  Eduard Rovira-Vallbona³ 

[1] National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam;U.S. Naval Medical Research Unit TWO, Singapore, Singapore;Vysnova Partners, Landover, MD, USA;

关键词: Malaria;    Plasmodium falciparum;    Diagnostics;    Rapid Diagnostic Test;    Histidine rich protein 2;    Histidine rich protein 3;    Gene deletion;    Surveillance;    Vietnam;   

DOI  :  10.1186/s12936-022-04399-w

 received in 2022-09-25, accepted in 2022-11-22,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundMalaria rapid diagnostic tests (RDTs) remain the main point-of-care tests for diagnosis of symptomatic Plasmodium falciparum malaria in endemic areas. However, parasites with gene deletions in the most common RDT target, histidine rich protein 2 (pfhrp2/HRP2), can produce false-negative RDT results leading to inadequate case management. The objective of this study was to determine the prevalence of hrp2/3 deletions causing false-negative RDT results in Vietnam (Gia Lai and Dak Lak provinces).MethodsIndividuals presenting with malaria symptoms at health facilities were screened for P. falciparum infection using light microscopy and HRP2-RDT (SD Bioline Malaria Antigen Pf/Pv RDT, Abbott). Microscopically confirmed P. falciparum infections were analysed for parasite species by 18S rRNA qPCR, and pfhrp2 and pfhrp3 exon2 deletions were investigated by nested PCR. pfhrp2 amplicons were sequenced by the Sanger method and HRP2 plasma levels were determined by enzyme-linked immunosorbent assay (ELISA).ResultsThe prevalence of false-negative RDT results among symptomatic cases was 5.6% (15/270). No pfhrp2 and pfhrp3 deletions were identified. False-negative RDT results were associated with lower parasite density (p = 0.005) and lower HRP2 plasma concentrations (p < 0.001), as compared to positive RDT.ConclusionsThe absence of hrp2/3 deletions detected in this survey suggests that HRP2-based malaria RDTs remain effective for the diagnosis of symptomatic P. falciparum malaria in Central Vietnam.

【 授权许可】

CC BY   
© The Author(s) 2022

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