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An assessment of various blood collection and transfer methods used for malaria rapid diagnostic tests.

Luchavez J, Lintag ME, Coll-Black M, Baik F, Bell D - Malar. J. (2007)

Bottom Line: Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes.The effect of varying blood volumes on RDT sensitivity and ease of use was also observed.Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Institute for Tropical Medicine, Filinvest Compound, Alabang, Muntinlupa, Philippines. jluchavez@yahoo.com

ABSTRACT

Background: Four blood collection and transfer devices commonly used for malaria rapid diagnostic tests (RDTs) were assessed for their consistency, accuracy and ease of use in the hands of laboratory technicians and village health workers.

Methods: Laboratory technicians and village health workers collected blood from a finger prick using each device in random order, and deposited the blood either on filter paper or into a suitable casette-type RDT. Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes. The effect of varying blood volumes on RDT sensitivity and ease of use was also observed.

Results: There was high variability in blood volume collected by the devices, with the straw and the loop, the most preferred devices, usually transferring volumes greater than intended, while the glass capillary tube and the plastic pipette transferring less volume than intended or none at all. Varying the blood volume delivered to RDTs indicated that this variation is critical to RDT sensitivity only when the transferred volume is very low.

Conclusion: None of the blood transfer devices assessed performed consistently well. Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

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Related in: MedlinePlus

Blood collection and transfer devices. The plastic straw and plastic loop collect a film of blood by touching the finger prick; the glass tube collects blood by capillary action, while the plastic pipette aspirates blood similar to a conventional dropper.
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Figure 1: Blood collection and transfer devices. The plastic straw and plastic loop collect a film of blood by touching the finger prick; the glass tube collects blood by capillary action, while the plastic pipette aspirates blood similar to a conventional dropper.

Mentions: This study was performed in the Philippines, using four commonly used blood transfer devices: a plastic straw and a plastic loop (both from Paracheck Pf, Orchid Biomedicals, India), a plastic pipette (OptiMal-IT, Diamed AG, Switzerland), and glass capillary tube (ICT Malaria Combo Cassette, R&R Marketing, South Africa) (Figure 1). The straw, loop and capillary tube are designed to collect 5 μL by touching the blood drop on the finger prick, while the plastic pipette is intended to aspirate 10 μL. Except for the pipette, which is designed to transfer blood into a well, these devices are designed for use with cassette-type RDTs. Only adults were used as donors for blood sampling.


An assessment of various blood collection and transfer methods used for malaria rapid diagnostic tests.

Luchavez J, Lintag ME, Coll-Black M, Baik F, Bell D - Malar. J. (2007)

Blood collection and transfer devices. The plastic straw and plastic loop collect a film of blood by touching the finger prick; the glass tube collects blood by capillary action, while the plastic pipette aspirates blood similar to a conventional dropper.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2194690&req=5

Figure 1: Blood collection and transfer devices. The plastic straw and plastic loop collect a film of blood by touching the finger prick; the glass tube collects blood by capillary action, while the plastic pipette aspirates blood similar to a conventional dropper.
Mentions: This study was performed in the Philippines, using four commonly used blood transfer devices: a plastic straw and a plastic loop (both from Paracheck Pf, Orchid Biomedicals, India), a plastic pipette (OptiMal-IT, Diamed AG, Switzerland), and glass capillary tube (ICT Malaria Combo Cassette, R&R Marketing, South Africa) (Figure 1). The straw, loop and capillary tube are designed to collect 5 μL by touching the blood drop on the finger prick, while the plastic pipette is intended to aspirate 10 μL. Except for the pipette, which is designed to transfer blood into a well, these devices are designed for use with cassette-type RDTs. Only adults were used as donors for blood sampling.

Bottom Line: Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes.The effect of varying blood volumes on RDT sensitivity and ease of use was also observed.Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Institute for Tropical Medicine, Filinvest Compound, Alabang, Muntinlupa, Philippines. jluchavez@yahoo.com

ABSTRACT

Background: Four blood collection and transfer devices commonly used for malaria rapid diagnostic tests (RDTs) were assessed for their consistency, accuracy and ease of use in the hands of laboratory technicians and village health workers.

Methods: Laboratory technicians and village health workers collected blood from a finger prick using each device in random order, and deposited the blood either on filter paper or into a suitable casette-type RDT. Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes. The effect of varying blood volumes on RDT sensitivity and ease of use was also observed.

Results: There was high variability in blood volume collected by the devices, with the straw and the loop, the most preferred devices, usually transferring volumes greater than intended, while the glass capillary tube and the plastic pipette transferring less volume than intended or none at all. Varying the blood volume delivered to RDTs indicated that this variation is critical to RDT sensitivity only when the transferred volume is very low.

Conclusion: None of the blood transfer devices assessed performed consistently well. Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

Show MeSH
Related in: MedlinePlus