Reliable enumeration of malaria parasites in thick blood films using digital image analysis
Abstract Background Quantitation of malaria parasite density is an important component of laboratory diagnosis of malaria. Microscopy of Giemsa-stained thick blood films is the conventional method for parasite enumeration. Accurate and reproducible parasite counts are difficult to achieve, because o...
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ftdoajarticles:oai:doaj.org/article:de200f0345d74278b19d1d6993ee5969 2023-05-15T15:11:40+02:00 Reliable enumeration of malaria parasites in thick blood films using digital image analysis Frean John A 2009-09-01T00:00:00Z https://doi.org/10.1186/1475-2875-8-218 https://doaj.org/article/de200f0345d74278b19d1d6993ee5969 EN eng BMC http://www.malariajournal.com/content/8/1/218 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-8-218 1475-2875 https://doaj.org/article/de200f0345d74278b19d1d6993ee5969 Malaria Journal, Vol 8, Iss 1, p 218 (2009) Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 article 2009 ftdoajarticles https://doi.org/10.1186/1475-2875-8-218 2022-12-31T09:09:29Z Abstract Background Quantitation of malaria parasite density is an important component of laboratory diagnosis of malaria. Microscopy of Giemsa-stained thick blood films is the conventional method for parasite enumeration. Accurate and reproducible parasite counts are difficult to achieve, because of inherent technical limitations and human inconsistency. Inaccurate parasite density estimation may have adverse clinical and therapeutic implications for patients, and for endpoints of clinical trials of anti-malarial vaccines or drugs. Digital image analysis provides an opportunity to improve performance of parasite density quantitation. Methods Accurate manual parasite counts were done on 497 images of a range of thick blood films with varying densities of malaria parasites, to establish a uniformly reliable standard against which to assess the digital technique. By utilizing descriptive statistical parameters of parasite size frequency distributions, particle counting algorithms of the digital image analysis programme were semi-automatically adapted to variations in parasite size, shape and staining characteristics, to produce optimum signal/noise ratios. Results A reliable counting process was developed that requires no operator decisions that might bias the outcome. Digital counts were highly correlated with manual counts for medium to high parasite densities, and slightly less well correlated with conventional counts. At low densities (fewer than 6 parasites per analysed image) signal/noise ratios were compromised and correlation between digital and manual counts was poor. Conventional counts were consistently lower than both digital and manual counts. Conclusion Using open-access software and avoiding custom programming or any special operator intervention, accurate digital counts were obtained, particularly at high parasite densities that are difficult to count conventionally. The technique is potentially useful for laboratories that routinely perform malaria parasite enumeration. The requirements of a ... Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic Malaria Journal 8 1 |
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Directory of Open Access Journals: DOAJ Articles |
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Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
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Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 Frean John A Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
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Arctic medicine. Tropical medicine RC955-962 Infectious and parasitic diseases RC109-216 |
description |
Abstract Background Quantitation of malaria parasite density is an important component of laboratory diagnosis of malaria. Microscopy of Giemsa-stained thick blood films is the conventional method for parasite enumeration. Accurate and reproducible parasite counts are difficult to achieve, because of inherent technical limitations and human inconsistency. Inaccurate parasite density estimation may have adverse clinical and therapeutic implications for patients, and for endpoints of clinical trials of anti-malarial vaccines or drugs. Digital image analysis provides an opportunity to improve performance of parasite density quantitation. Methods Accurate manual parasite counts were done on 497 images of a range of thick blood films with varying densities of malaria parasites, to establish a uniformly reliable standard against which to assess the digital technique. By utilizing descriptive statistical parameters of parasite size frequency distributions, particle counting algorithms of the digital image analysis programme were semi-automatically adapted to variations in parasite size, shape and staining characteristics, to produce optimum signal/noise ratios. Results A reliable counting process was developed that requires no operator decisions that might bias the outcome. Digital counts were highly correlated with manual counts for medium to high parasite densities, and slightly less well correlated with conventional counts. At low densities (fewer than 6 parasites per analysed image) signal/noise ratios were compromised and correlation between digital and manual counts was poor. Conventional counts were consistently lower than both digital and manual counts. Conclusion Using open-access software and avoiding custom programming or any special operator intervention, accurate digital counts were obtained, particularly at high parasite densities that are difficult to count conventionally. The technique is potentially useful for laboratories that routinely perform malaria parasite enumeration. The requirements of a ... |
format |
Article in Journal/Newspaper |
author |
Frean John A |
author_facet |
Frean John A |
author_sort |
Frean John A |
title |
Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
title_short |
Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
title_full |
Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
title_fullStr |
Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
title_full_unstemmed |
Reliable enumeration of malaria parasites in thick blood films using digital image analysis |
title_sort |
reliable enumeration of malaria parasites in thick blood films using digital image analysis |
publisher |
BMC |
publishDate |
2009 |
url |
https://doi.org/10.1186/1475-2875-8-218 https://doaj.org/article/de200f0345d74278b19d1d6993ee5969 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
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Arctic |
op_source |
Malaria Journal, Vol 8, Iss 1, p 218 (2009) |
op_relation |
http://www.malariajournal.com/content/8/1/218 https://doaj.org/toc/1475-2875 doi:10.1186/1475-2875-8-218 1475-2875 https://doaj.org/article/de200f0345d74278b19d1d6993ee5969 |
op_doi |
https://doi.org/10.1186/1475-2875-8-218 |
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Malaria Journal |
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8 |
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1 |
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1766342493670998016 |