FIND Foundation for Innovative New Diagnostics

Genève, Switzerland

FIND Foundation for Innovative New Diagnostics

Genève, Switzerland
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Incardona S.,FIND Foundation for Innovative New Diagnostics | Lussiana C.,Population Services International | Streat E.,Malaria Consortium | Dolan S.,Population Services International | And 7 more authors.
Malaria Journal | Year: 2017

Background: Use of antigen-detecting malaria rapid diagnostic tests (RDTs) has increased exponentially over the last decade. WHO's Global Malaria Programme, FIND, and other collaborators have established a quality assurance scheme to guide product selection, lot verification, transport, storage, and training procedures. Recent concerns over the quality of buffer packaging and test accessories suggest a need to include these items in product assessments. This paper describes quality problems with buffer and accessories encountered in a project promoting private sector RDT use in five African countries and suggests steps to avoid or more rapidly identify and resolve such problems. Methods: Private provider complaints about RDT buffer vials and kit accessories were collected during supervisory visits, and a standard assessment process was developed. Using 100 tests drawn from six different lots produced by two manufacturers, lab technicians visually assessed alcohol swab packaging, blood transfer device (BTD) usability, and buffer appearance, then calculated mean blood volume from 10 BTD transfers and mean buffer volume from 10 individual buffer vials. WHO guided complaint reporting and follow-up with manufacturers. Results: Supervisory visits confirmed user reports of dry alcohol swabs, poorly functioning BTDs, and non-uniform volumes of buffer. Lot testing revealed further evidence of quality problems, leading one manufacturer to replace buffer vials and accessories for 40,000 RDTs. In December 2014, WHO issued an Information Notice for Users regarding variable buffer volumes in single-use vials and recommended against procurement of these products until defects were addressed. Discussion: Though not necessarily comprehensive or generalizable, the findings presented here highlight the need for extending quality assessment to all malaria RDT test kit contents. Defects such as those described in this paper could reduce test accuracy and increase probability of invalid, false positive, or false negative results. Such deficiencies could undermine provider confidence in RDTs, prompting a return to presumptive treatment or reliance on poor quality microscopy. In partial response to this experience, WHO, FIND, and other project partners have developed guidance on documenting, troubleshooting, reporting, and resolving such problems when they occur. © 2017 The Author(s).


Gatton M.L.,Queensland University of Technology | Rees-Channer R.R.,University College London | Glenn J.,Centers for Disease Control and Prevention | Barnwell J.W.,Centers for Disease Control and Prevention | And 6 more authors.
Malaria Journal | Year: 2015

Background: Malaria rapid diagnostic tests (RDTs) are appropriate for case management, but persistent antigenaemia is a concern for HRP2-detecting RDTs in endemic areas. It has been suggested that pan-pLDH test bands on combination RDTs could be used to distinguish persistent antigenaemia from active Plasmodium falciparum infection, however this assumes all active infections produce positive results on both bands of RDTs, an assertion that has not been demonstrated. Methods: In this study, data generated during the WHO-FIND product testing programme for malaria RDTs was reviewed to investigate the reactivity of individual test bands against P. falciparum in 18 combination RDTs. Each product was tested against multiple wild-type P. falciparum only samples. Antigen levels were measured by quantitative ELISA for HRP2, pLDH and aldolase. Results: When tested against P. falciparum samples at 200 parasites/μL, 92% of RDTs were positive; 57% of these on both the P. falciparum and pan bands, while 43% were positive on the P. falciparum band only. There was a relationship between antigen concentration and band positivity; ≥4 ng/mL of HRP2 produced positive results in more than 95% of P. falciparum bands, while ≥45 ng/mL of pLDH was required for at least 90% of pan bands to be positive. Conclusions: In active P. falciparum infections it is common for combination RDTs to return a positive HRP2 band combined with a negative pan-pLDH band, and when both bands are positive, often the pan band is faint. Thus active infections could be missed if the presence of a HRP2 band in the absence of a pan band is interpreted as being caused solely by persistent antigenaemia. © 2015 Gatton et al.; licensee BioMed Central.


PubMed | Centers for Disease Control and Prevention, World Health Organization, FIND Foundation for Innovative New Diagnostics, Queensland University of Technology and 2 more.
Type: | Journal: Malaria journal | Year: 2015

Malaria rapid diagnostic tests (RDTs) are appropriate for case management, but persistent antigenaemia is a concern for HRP2-detecting RDTs in endemic areas. It has been suggested that pan-pLDH test bands on combination RDTs could be used to distinguish persistent antigenaemia from active Plasmodium falciparum infection, however this assumes all active infections produce positive results on both bands of RDTs, an assertion that has not been demonstrated.In this study, data generated during the WHO-FIND product testing programme for malaria RDTs was reviewed to investigate the reactivity of individual test bands against P. falciparum in 18 combination RDTs. Each product was tested against multiple wild-type P. falciparum only samples. Antigen levels were measured by quantitative ELISA for HRP2, pLDH and aldolase.When tested against P. falciparum samples at 200 parasites/L, 92% of RDTs were positive; 57% of these on both the P. falciparum and pan bands, while 43% were positive on the P. falciparum band only. There was a relationship between antigen concentration and band positivity; 4ng/mL of HRP2 produced positive results in more than 95% of P. falciparum bands, while 45ng/mL of pLDH was required for at least 90% of pan bands to be positive.In active P. falciparum infections it is common for combination RDTs to return a positive HRP2 band combined with a negative pan-pLDH band, and when both bands are positive, often the pan band is faint. Thus active infections could be missed if the presence of a HRP2 band in the absence of a pan band is interpreted as being caused solely by persistent antigenaemia.


Albertini A.,FIND Foundation for Innovative New Diagnostics | Djalle D.,Institute Pasteur Bangui | Faye B.,Cheikh Anta Diop University | Gamboa D.,Cayetano Heredia Peruvian University | And 7 more authors.
Tropical Medicine and International Health | Year: 2012

Objectives This enquiry aimed to provide a snap-shot of availability, price and quality of malaria rapid diagnostic tests (RDTs) in private health facilities at selected sites in six malaria-endemic countries in Africa, South East Asia and South America. Methods In each study site, data collectors surveyed private healthcare facilities which were selected based on accessibility from their home institution. Using a questionnaire, information was recorded about the facility itself and the malaria RDT(s) available. Where possible, a small number of RDTs were procured and quality control tested using a standardized procedure. Results Of the 324 private healthcare facilities visited, 35 outlets (mainly private clinics and hospitals) were found to supply 10 different types of RDTs products. RDT prices across the six countries ranged from US$1.00 to $16.81. Five of the 14 malaria RDTs collected failed quality control testing. Conclusions In the private outlets sampled, the availability of RDTs was limited. Some of the RDTs whose quality we tested demonstrated inadequate sensitivity. This presents a number of risks. Given the more widespread distribution of antimalarials currently planned for private sector facilities, parasite-based diagnosis in this sector will be essential to adhere to the WHO guidelines for effective case management of malaria. Considerable regulation and quality control are also necessary to assure the availability of accurate and reliable RDTs, as well as adequate case management and provider adherence to RDT results. Public sector engagement is likely to be essential in this process. © 2011 Blackwell Publishing Ltd.


Polley S.D.,University College London | Bell D.,Intellectual Ventures Laboratory | Oliver J.,42 Technology | Tully F.,42 Technology | And 4 more authors.
Malaria Journal | Year: 2015

Background: Dried blood spots are a common medium for collecting patient blood prior to testing for malaria by molecular methods. A new shaped filter device for the quick and simple collection of a designated volume of patient blood has been designed and tested against conventional blood spots for accuracy and precision. Methods: Shaped filter devices were laser cut from Whatman GB003 paper to absorb a 20 μl blood volume. These devices were used to sample Plasmodium falciparum infected blood and the volume absorbed was measured volumetrically. Conventional blood spots were made by pipetting 20 μl of the same blood onto Whatman 3MM paper. DNA was extracted from both types of dried blood spot using Qiagen DNA blood mini or Chelex extraction for real-time PCR analysis, and PURE extraction for malaria LAMP testing. Results: The shaped filter devices collected a mean volume of 21.1 μl of blood, with a coefficient of variance of 8.1%. When used for DNA extraction by Chelex and Qiagen methodologies the mean number of international standard units of P. falciparum DNA recovered per μl of the eluate was 53.1 (95% CI: 49.4 to 56.7) and 32.7 (95% CI: 28.8 to 36.6), respectively for the shaped filter device, and 54.6 (95% CI: 52.1 to 57.1) and 12.0 (95% CI: 9.9 to 14.1), respectively for the 3MM blood spots. Qiagen extraction of 200 μl of whole infected blood yielded 853.6 international standard units of P. falciparum DNA per μl of eluate. Conclusions: A shaped filter device provides a simple way to quickly sample and store a defined volume of blood without the need for any additional measuring devices. Resultant dried blood spots may be employed for DNA extraction using a variety of technologies for nucleic acid amplification without the need for repeated cleaning of scissors or punches to prevent cross contamination of samples and results are comparable to traditional DBS. © 2015 Polley et al.; licensee BioMed Central.


PubMed | Intellectual Ventures Laboratory, FIND Foundation for Innovative New Diagnostics, University College London and 42 Technology
Type: | Journal: Malaria journal | Year: 2015

Dried blood spots are a common medium for collecting patient blood prior to testing for malaria by molecular methods. A new shaped filter device for the quick and simple collection of a designated volume of patient blood has been designed and tested against conventional blood spots for accuracy and precision.Shaped filter devices were laser cut from Whatman GB003 paper to absorb a 20l blood volume. These devices were used to sample Plasmodium falciparum infected blood and the volume absorbed was measured volumetrically. Conventional blood spots were made by pipetting 20l of the same blood onto Whatman 3MM paper. DNA was extracted from both types of dried blood spot using Qiagen DNA blood mini or Chelex extraction for real-time PCR analysis, and PURE extraction for malaria LAMP testing.The shaped filter devices collected a mean volume of 21.1l of blood, with a coefficient of variance of 8.1%. When used for DNA extraction by Chelex and Qiagen methodologies the mean number of international standard units of P. falciparum DNA recovered per l of the eluate was 53.1 (95% CI: 49.4 to 56.7) and 32.7 (95% CI: 28.8 to 36.6), respectively for the shaped filter device, and 54.6 (95% CI: 52.1 to 57.1) and 12.0 (95% CI: 9.9 to 14.1), respectively for the 3MM blood spots. Qiagen extraction of 200l of whole infected blood yielded 853.6 international standard units of P. falciparum DNA per l of eluate.A shaped filter device provides a simple way to quickly sample and store a defined volume of blood without the need for any additional measuring devices. Resultant dried blood spots may be employed for DNA extraction using a variety of technologies for nucleic acid amplification without the need for repeated cleaning of scissors or punches to prevent cross contamination of samples and results are comparable to traditional DBS.


PubMed | FIND Foundation for Innovative New Diagnostics
Type: Journal Article | Journal: Tropical medicine & international health : TM & IH | Year: 2012

This enquiry aimed to provide a snap-shot of availability, price and quality of malaria rapid diagnostic tests (RDTs) in private health facilities at selected sites in six malaria-endemic countries in Africa, South East Asia and South America.In each study site, data collectors surveyed private healthcare facilities which were selected based on accessibility from their home institution. Using a questionnaire, information was recorded about the facility itself and the malaria RDT(s) available. Where possible, a small number of RDTs were procured and quality control tested using a standardized procedure.Of the 324 private healthcare facilities visited, 35 outlets (mainly private clinics and hospitals) were found to supply 10 different types of RDTs products. RDT prices across the six countries ranged from US$1.00 to $16.81. Five of the 14 malaria RDTs collected failed quality control testing.In the private outlets sampled, the availability of RDTs was limited. Some of the RDTs whose quality we tested demonstrated inadequate sensitivity. This presents a number of risks. Given the more widespread distribution of antimalarials currently planned for private sector facilities, parasite-based diagnosis in this sector will be essential to adhere to the WHO guidelines for effective case management of malaria. Considerable regulation and quality control are also necessary to assure the availability of accurate and reliable RDTs, as well as adequate case management and provider adherence to RDT results. Public sector engagement is likely to be essential in this process.

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