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A systematic review of sub-microscopic Plasmodium vivax infection

BACKGROUND: An accurate estimate of Plasmodiumvivax prevalence is essential for the successful implementation of malaria control and elimination programmes. Prevalence estimates both inform control strategies and are used in their evaluation. Light microscopy is the main method for detecting Plasmod...

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Autores principales: Moreira, Clarissa M., Abo-Shehada, Mahmoud, Price, Ric N., Drakeley, Chris J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4578340/
https://www.ncbi.nlm.nih.gov/pubmed/26390924
http://dx.doi.org/10.1186/s12936-015-0884-z
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author Moreira, Clarissa M.
Abo-Shehada, Mahmoud
Price, Ric N.
Drakeley, Chris J.
author_facet Moreira, Clarissa M.
Abo-Shehada, Mahmoud
Price, Ric N.
Drakeley, Chris J.
author_sort Moreira, Clarissa M.
collection PubMed
description BACKGROUND: An accurate estimate of Plasmodiumvivax prevalence is essential for the successful implementation of malaria control and elimination programmes. Prevalence estimates both inform control strategies and are used in their evaluation. Light microscopy is the main method for detecting Plasmodium parasitaemia in the peripheral blood, but compared to molecular diagnostics, such as polymerase chain reaction (PCR), has limited sensitivity. METHODS: A systematic review and meta-analysis was conducted to assess the effect of detection method on the prevalence of P.vivax and to quantify the extent to which P. vivax infections are undetected by microscopy. Embase, Medline and the Cochrane Database were searched for studies reporting prevalence by PCR and by microscopy and that contained all of the following key words: vivax, PCR, and malaria. Prevalence estimates and study meta-data were extracted systematically from each publication. Combined microscopy:PCR prevalence ratios were estimated by random effects meta-analysis. Sensitivity and specificity of microscopy were calculated using PCR as the gold standard. RESULTS: Of 874 studies reviewed, 40 met the criteria for inclusion contributing 54 prevalence pairs. The prevalence of P.vivax infection measured by PCR was consistently higher than the prevalence measured by microscopy with sub-patent parasitaemia. The mean prevalence of infection detected by microscopy was 67 % (95 % CI 59–73 %) lower than the prevalence detected by PCR. The detection of sub-patent parasitaemia did not vary according to the microscopy method (thick or, thick and thin smears), the PCR prevalence (as a measure of the true P.vivax prevalence), the type of blood used or DNA extraction method. CONCLUSIONS: Quantifying P. vivax parasitaemia by PCR rather than microscopy consistently increased prevalence estimates by a factor of 2.3. Whilst the sensitivity of microscopy can be improved by better methods, molecular methods have potential to be scaled up to improve the detection of P. vivax transmission reservoirs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12936-015-0884-z) contains supplementary material, which is available to authorized users.
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spelling pubmed-45783402015-09-23 A systematic review of sub-microscopic Plasmodium vivax infection Moreira, Clarissa M. Abo-Shehada, Mahmoud Price, Ric N. Drakeley, Chris J. Malar J Research BACKGROUND: An accurate estimate of Plasmodiumvivax prevalence is essential for the successful implementation of malaria control and elimination programmes. Prevalence estimates both inform control strategies and are used in their evaluation. Light microscopy is the main method for detecting Plasmodium parasitaemia in the peripheral blood, but compared to molecular diagnostics, such as polymerase chain reaction (PCR), has limited sensitivity. METHODS: A systematic review and meta-analysis was conducted to assess the effect of detection method on the prevalence of P.vivax and to quantify the extent to which P. vivax infections are undetected by microscopy. Embase, Medline and the Cochrane Database were searched for studies reporting prevalence by PCR and by microscopy and that contained all of the following key words: vivax, PCR, and malaria. Prevalence estimates and study meta-data were extracted systematically from each publication. Combined microscopy:PCR prevalence ratios were estimated by random effects meta-analysis. Sensitivity and specificity of microscopy were calculated using PCR as the gold standard. RESULTS: Of 874 studies reviewed, 40 met the criteria for inclusion contributing 54 prevalence pairs. The prevalence of P.vivax infection measured by PCR was consistently higher than the prevalence measured by microscopy with sub-patent parasitaemia. The mean prevalence of infection detected by microscopy was 67 % (95 % CI 59–73 %) lower than the prevalence detected by PCR. The detection of sub-patent parasitaemia did not vary according to the microscopy method (thick or, thick and thin smears), the PCR prevalence (as a measure of the true P.vivax prevalence), the type of blood used or DNA extraction method. CONCLUSIONS: Quantifying P. vivax parasitaemia by PCR rather than microscopy consistently increased prevalence estimates by a factor of 2.3. Whilst the sensitivity of microscopy can be improved by better methods, molecular methods have potential to be scaled up to improve the detection of P. vivax transmission reservoirs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12936-015-0884-z) contains supplementary material, which is available to authorized users. BioMed Central 2015-09-22 /pmc/articles/PMC4578340/ /pubmed/26390924 http://dx.doi.org/10.1186/s12936-015-0884-z Text en © Moreira et al. 2015 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. 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.
spellingShingle Research
Moreira, Clarissa M.
Abo-Shehada, Mahmoud
Price, Ric N.
Drakeley, Chris J.
A systematic review of sub-microscopic Plasmodium vivax infection
title A systematic review of sub-microscopic Plasmodium vivax infection
title_full A systematic review of sub-microscopic Plasmodium vivax infection
title_fullStr A systematic review of sub-microscopic Plasmodium vivax infection
title_full_unstemmed A systematic review of sub-microscopic Plasmodium vivax infection
title_short A systematic review of sub-microscopic Plasmodium vivax infection
title_sort systematic review of sub-microscopic plasmodium vivax infection
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4578340/
https://www.ncbi.nlm.nih.gov/pubmed/26390924
http://dx.doi.org/10.1186/s12936-015-0884-z
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