Re-evaluation of microscopy confirmed Plasmodium falciparum and Plasmodium vivax malaria by nested PCR detection in southern Ethiopia

Malaria Journal

Research

Girmay Medhin¹  Nega Berhe¹  Seleshi Kebede Mekonnen²  Abraham Aseffa³  Thirumalaisamy P Velavan⁴ 

[1] Aklilu Lemma Institute of Pathobiology, Addis Abba University, Addis Abba, Ethiopia;Aklilu Lemma Institute of Pathobiology, Addis Abba University, Addis Abba, Ethiopia;Armauer Hansen Research Institute, Addis Abba, Ethiopia;Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany;Armauer Hansen Research Institute, Addis Abba, Ethiopia;Institute of Tropical Medicine, University of Tübingen, Wilhelmstraße 27, 72074, Tübingen, Germany;

关键词: Malaria;    Plasmodium;    Nested PCR;    Microscopy;    Ethiopia;   

DOI  :  10.1186/1475-2875-13-48

 received in 2013-11-12, accepted in 2014-02-04,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundWith 75% of the Ethiopian population at risk of malaria, accurate diagnosis is crucial for malaria treatment in endemic areas where Plasmodium falciparum and Plasmodium vivax co-exist. The present study evaluated the performance of regular microscopy in accurate identification of Plasmodium spp. in febrile patients visiting health facilities in southern Ethiopia.MethodsA cross-sectional study design was employed to recruit study subjects who were microscopically positive for malaria parasites and attending health facilities in southern Ethiopia between August and December 2011. Of the 1,416 febrile patients attending primary health facilities, 314 febrile patients, whose slides were positive for P. falciparum, P. vivax or mixed infections using microscopy, were re-evaluated for their infection status by PCR. Finger-prick blood samples were used for parasite genomic DNA extraction. Phylogenetic analyses were performed to reconstruct the distribution of different Plasmodium spp. across the three geographical areas.ResultsOf the 314 patients with a positive thick blood smear, seven patients (2%) were negative for any of the Plasmodium spp. by nested PCR. Among 180 microscopically diagnosed P. falciparum cases, 111 (61.7%) were confirmed by PCR, 44 (24.4%) were confirmed as P. vivax, 18 (10%) had mixed infections with P. falciparum and P. vivax and two (1.1%) were mixed infections with P. falciparum and P. malariae and five (2.8%) were negative for any of the Plasmodium spp. Of 131 microscopically diagnosed P. vivax cases, 110 (84%) were confirmed as P. vivax, 14 (10.7%) were confirmed as P. falciparum, two (1.5%) were P. malariae, three (2.3%) with mixed infections with P. falciparum and P. vivax and two (1.5%) were negative for any of the Plasmodium spp. Plasmodium falciparum and P. vivax mixed infections were observed. Plasmodium malariae was detected as mono and mixed infections in four individuals.ConclusionFalse positivity, under-reporting of mixed infections and a significant number of species mismatch needs attention and should be improved for appropriate diagnosis. The detection of substantial number of false positive results by molecular methodologies may provide the accurate incidence of circulating Plasmodium species in the geographical region and has important repercussions in understanding malaria epidemiology and subsequent control.

【 授权许可】

Unknown   
© Mekonnen et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.