Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2006 Dec 14:5:121.
doi: 10.1186/1475-2875-5-121.

Comparison of PCR and microscopy for the detection of asymptomatic malaria in a Plasmodium falciparum/vivax endemic area in Thailand

Russell E Coleman  1 , Jetsumon Sattabongkot, Sommai Promstaporm, Nongnuj Maneechai, Bousaraporn Tippayachai, Ampornpan Kengluecha, Nattawan Rachapaew, Gabriela Zollner, Robert Scott Miller, Jefferson A Vaughan, Krongtong Thimasarn, Benjawan Khuntirat
Affiliations

Comparison of PCR and microscopy for the detection of asymptomatic malaria in a Plasmodium falciparum/vivax endemic area in Thailand

Russell E Coleman et al. Malar J. .

Abstract

Objective: The main objective of this study was to compare the performance of nested PCR with expert microscopy as a means of detecting Plasmodium parasites during active malaria surveillance in western Thailand.

Methods: The study was performed from May 2000 to April 2002 in the village of Kong Mong Tha, located in western Thailand. Plasmodium vivax (PV) and Plasmodium falciparum (PF) are the predominant parasite species in this village, followed by Plasmodium malariae (PM) and Plasmodium ovale (PO). Each month, fingerprick blood samples were taken from each participating individual and used to prepare thick and thin blood films and for PCR analysis.

Results: PCR was sensitive (96%) and specific (98%) for malaria at parasite densities > or = 500/microl; however, only 18% (47/269) of P. falciparum- and 5% (20/390) of P. vivax-positive films had parasite densities this high. Performance of PCR decreased markedly at parasite densities <500/microl, with sensitivity of only 20% for P. falciparum and 24% for P. vivax at densities <100 parasites/microl.

Conclusion: Although PCR performance appeared poor when compared to microscopy, data indicated that the discrepancy between the two methods resulted from poor performance of microscopy at low parasite densities rather than poor performance of PCR. These data are not unusual when the diagnostic method being evaluated is more sensitive than the reference method. PCR appears to be a useful method for detecting Plasmodium parasites during active malaria surveillance in Thailand.

PubMed Disclaimer

References

    1. Moody A. Rapid diagnostic tests for malaria parasites. Clin Microbiol Rev. 2000;15:66–78. doi: 10.1128/CMR.15.1.66-78.2002. - DOI - PMC - PubMed
    1. Makler MT, Palmer CJ, Ager AL. A review of practical techniques for the diagnosis of malaria. Ann Trop Med Parasitol. 1998;92:419–433. doi: 10.1080/00034989859401. - DOI - PubMed
    1. Singh B. Molecular methods for diagnosis and epidemiological studies of parasitic infections. Int J Parasitol. 1997;27:1135–1145. doi: 10.1016/S0020-7519(97)00111-2. - DOI - PubMed
    1. Siripoon N, Snounou G, Yamogkul P, Na-Bangchang K, Thaithong S. Cryptic Plasmodium falciparum parasites in clinical P. vivax blood samples from Thailand. Trans R Soc Trop Med Hyg. 2002;96:70–71. doi: 10.1016/S0035-9203(02)90246-4. - DOI - PubMed
    1. Mayxay M, Pukritrayakamee S, Chotivanich K, Imwong M, Looareesuwan S, White NJ. Identification of cryptic coinfection with Plasmodium falciparum in patients presenting with vivax malaria. Am J Trop Med Hyg. 2001;65:588–592. - PubMed

Publication types

MeSH terms

LinkOut - more resources