Comparison of diagnostic methods for the detection and quantification of the four sympatric Plasmodium species in field samples from Papua New Guinea

Malaria Journal

Research

Hernando A del Portillo¹  Peter A Zimmerman²  Céline Barnadas³  Inoni Betuela³  Peter Siba³  Ivo Mueller³  Jonah Iga³  Anna Rosanas-Urgell⁴  Dania Mueller⁵  Ingrid Felger⁵ 

[1] Barcelona Centre for International Health Research (CRESIB), Hospital Clinic/IDIBAPS, Universitat de Barcelona, Roselló 132, 4a planta, 08036, Barcelona, Spain;Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain;Center for Global Health and Diseases, Case Western Reserve University School of Medicine, Cleveland, Ohio;Papua New Guinea Insitute of Medical Research, Madang 511, Papua New Guinea;Papua New Guinea Insitute of Medical Research, Madang 511, Papua New Guinea;Barcelona Centre for International Health Research (CRESIB), Hospital Clinic/IDIBAPS, Universitat de Barcelona, Roselló 132, 4a planta, 08036, Barcelona, Spain;Swiss Tropical and Public Health Institute, Socinstrasse 57, CH-4002, Basel, Switzerland;University of Basel, Petersplatz 1, CH-4003, Basel, Switzerland;

关键词: Malaria;    Plasmodium;    Mixed Infection;    Rapid Diagnostic Test;    Parasite Density;   

DOI  :  10.1186/1475-2875-9-361

 received in 2010-09-14, accepted in 2010-12-14,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundAccurate diagnosis of Plasmodium infections is essential for malaria morbidity and mortality reduction in tropical areas. Despite great advantages of light microscopy (LM) for malaria diagnosis, its limited sensitivity is a critical shortfall for epidemiological studies. Robust molecular diagnostics tools are thus needed.MethodsThe present study describes the development of a duplex quantitative real time PCR (qPCR) assay, which specifically detects and quantifies the four human Plasmodium species. Performance of this method was compared to PCR-ligase detection reaction-fluorescent microsphere assay (PCR_LDR_FMA), nested PCR (nPCR) and LM, using field samples collected from 452 children one to five years of age from the Sepik area in Papua New Guinea. Agreement between diagnostic methods was calcualted using kappa statistics.ResultsThe agreement of qPCR with other molecular diagnostic methods was substantial for the detection of P. falciparum, but was moderate for the detection of P. vivax, P. malariae and P. ovale. P. falciparum and P. vivax prevalence by qPCR was 40.9% and 65.7% respectively. This compares to 43.8% and 73.2% by nPCR and 47.1% and 67.5% by PCR_LDR_FMA. P. malariae and P. ovale prevalence was 4.7% and 7.3% by qPCR, 3.3% and 3.8% by nPCR, and 7.7% and 4.4% by PCR_LDR_FMA. Prevalence by LM was lower for all four species, being 25.4% for P. falciparum, 54.9% for P. vivax, 2.4% for P. malariae and 0.0% for P. ovale. The quantification by qPCR closely correlated with microscopic quantification for P. falciparum and P. vivax samples (R2 = 0.825 and R2 = 0.505, respectively). The low prevalence of P. malariae and P. ovale did not permit a solid comparative analysis of quantification for these species.ConclusionsThe qPCR assay developed proved optimal for detection of all four Plasmodium species. Densities by LM were well reflected in quantification results by qPCR, whereby congruence was better for P. falciparum than for P. vivax. This likely is a consequence of the generally lower P. vivax densities. Easy performance of the qPCR assay, a less laborious workflow and reduced risk of contamination, together with reduced costs per sample through reduced reaction volume, opens the possibility to implement qPCR in endemic settings as a suitable diagnostic tool for large epidemiological studies.

【 授权许可】

CC BY   
© Rosanas-Urgell et al; licensee BioMed Central Ltd. 2010