Persistence of Plasmodium falciparum HRP-2 antigenaemia after artemisinin combination therapy is not associated with gametocytes

Malaria Journal

Research

Chris Drakeley¹  Tate Oulton¹  Will J. R. Stone¹  Katharine A. Collins²  Kjerstin Lanke²  John Bradley³  Almahamoudou Mahamar⁴  Sidi M. Niambele⁴  Siaka Samaké⁴  Alassane Dicko⁴  Sekouba Keita⁴  Adama Sacko⁴  Sekou F. Traore⁴  Makonon Diallo⁴  Ahamadou Youssouf⁴  Koualy Sanogo⁴  Youssouf Sinaba⁴ 

[1] Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK;Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, The Netherlands;MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK;Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali;

关键词: Malaria;    Rapid diagnostic tests;    Lateral flow;    Ultra-sensitive RDT;    HRP-2;    Gametocytes;    Antigenaemia;    Infectiousness;   

DOI  :  10.1186/s12936-022-04387-0

 received in 2022-08-02, accepted in 2022-11-16,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundIn some settings, sensitive field diagnostic tools may be needed to achieve elimination of falciparum malaria. To this end, rapid diagnostic tests (RDTs) based on the detection of the Plasmodium falciparum protein HRP-2 are being developed with increasingly lower limits of detection. However, it is currently unclear how parasite stages that are unaffected by standard drug treatments may contribute to HRP-2 detectability and potentially confound RDT results even after clearance of blood stage infection. This study assessed the detectability of HRP-2 in periods of post-treatment residual gametocytaemia.MethodsA cohort of 100 P.falciparum infected, gametocyte positive individuals were treated with or without the gametocytocidal drug primaquine (PQ), alongside standard artemisinin-based combination therapy (ACT), in the context of a randomised clinical trial in Ouelessebougou, Mali. A quantitative ELISA was used to measure levels of HRP-2, and compared time to test negativity using a standard and ultra-sensitive RDT (uRDT) between residual gametocyte positive and negative groups.ResultsTime to test negativity was longest by uRDT, followed by ELISA and then standard RDT. No significant difference in time to negativity was found between the treatment groups with and without residual gametocytes: uRDT (HR 0.79 [95% CI 0.52–1.21], p = 0.28), RDT (HR 0.77 [95% CI 0.51–1.15], p = 0.20) or ELISA (HR 0.88 [95% CI 0.59–1.32], p = 0.53). Similarly, no difference was observed when adjusting for baseline asexual parasite density. Quantified levels of HRP-2 over time were similar between groups, with differences attributable to asexual parasite densities. Furthermore, no difference in levels of HRP-2 was found between individuals who were or were not infectious to mosquitoes (OR 1.19 [95% CI 0.98–1.46], p = 0.077).ConclusionsSurviving sexual stage parasites after standard ACT treatment do not contribute to the persistence of HRP-2 antigenaemia, and appear to have little impact on RDT results.

【 授权许可】

CC BY   
© The Author(s) 2022

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