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

Point-of-care diagnostics: recent developments in a pandemic age

In this review, we provide an overview of developments in point-of-care (POC) diagnostics during the COVID-19 pandemic. We review these advances within the framework of a holistic POC ecosystem, focusing on points of interest - both technological and non-technological - to POC researchers and test developers. Technologically, we review design choices in assay chemistry, microfluidics, and instrumentation towards nucleic acid and protein detection for severe acute respiratory coronavirus 2 (SARS-CoV-2), and away from the lab bench, developments that supported the unprecedented rapid development, scale up, and deployment of POC devices. We describe common features in the POC technologies that obtained Emergency Use Authorization (EUA) for nucleic acid, antigen, and antibody tests, and how these tests fit into four distinct POC use cases. We conclude with implications for future pandemics, infectious disease monitoring, and digital health.

Evaluation of the performance of health extension workers on malaria rapid diagnostic tests and predictor factors in Bahir Dar Zuria district, northwest Ethiopia: A cross-sectional study

Background

In Ethiopia, anti-malaria treatment is initiated after parasitological confirmation using blood film microscopy at health centers and hospitals, or serological rapid diagnostic tests at health posts. At health posts, the diagnosis is performed by health extension workers using rapid diagnostic tests after little training. However, there is paucity of data about the health extension workers’ performance on rapid diagnostic tests. Hence, periodic monitoring of the performances of health extension workers on malaria rapid diagnostic tests and predicted factors plays a pivotal role for the control of malaria.

Methods

A cross sectional study was conducted in May 2020, among 75 health extension workers working at health posts in Bahir Dar Zuria district, Northwest Ethiopia. Their performance on malaria rapid diagnostic tests was assessed by distributing known positive and negative samples as confirmed by investigators using both rapid diagnostic test and blood film microscopy. Test results from health extension workers were then compared with that of investigators. Procedural errors committed while performing the tests were assessed using observational checklist. Data were analyzed using SPSS software version 20.

Results

The overall sensitivity and specificity of health extension workers in detecting Plasmodium species were 96.8% and 98.7%, respectively with 97.3% result agreement between the health extension workers and investigators (kappa value = 0.949). The most common procedural errors committed by health extension workers was ‘not checking expiry date of the test kits’ followed by ‘not adhering to the appropriate time of reading results’ that 70.7% and 64% of the participants committed these errors, respectively. Total number of procedural errors committed by those who have got in-service training was decreased by 47.3% as compared to those without in-service training.

Conclusions

Health extension workers had high performance on malaria rapid diagnostic tests. However, in-service training and periodic supervision should be given in order to maximize performance on these tests.

DNA recovery from archived RDTs for genetic characterization of Plasmodium falciparum in a routine setting in Lambaréné, Gabon

Background

Rapid diagnostic tests (RDTs) have been described as a source of genetic material to analyse malaria parasites in proof-of-concept studies. The increasing use of RDTs (e.g., in focal or mass screening and treatment campaigns) makes this approach particularly attractive for large-scale investigations of parasite populations. In this study, the complexity of Plasmodium falciparum infections, parasite load and chloroquine resistance transporter gene mutations were investigated in DNA samples extracted from positive RDTs, obtained in a routine setting and archived at ambient temperature.

Methods

A total of 669 archived RDTs collected from malaria cases in urban, semi-urban and rural areas of central Gabon were used for P. falciparum DNA extraction. Performance of RDTs as a source of DNA for PCR was determined using: (i) amplification of a single copy merozoite surface protein 1 (msp1) gene followed by highly sensitive and automated capillary electrophoresis; (ii) genotyping of the pfcrt gene locus 72–76 using haplotype-specific-probe-based real-time PCR to characterize chloroquine resistance; and, (iii) real-time PCR targeting 18S genes to detect and quantify Plasmodium parasites.

Results

Out of the 669 archived RDTs, amplification of P. falciparum nucleic materials had a success rate of 97% for 18S real-time PCR, and 88% for the msp1 gene. The multiplicity of infections (MOI) of the whole population was 2.6 (95% CI 2.5–2.8). The highest number of alleles detected in one infection was 11. The MOI decreased with increasing age (β = − 0.0046, p = 0.02) and residence in Lambaréné was associated with smaller MOIs (p < 0.001). The overall prevalence of mutations associated with chloroquine resistance was 78.5% and was not associated with age. In Lambaréné, prevalence of chloroquine resistance was lower compared to rural Moyen-Ogooué (β = − 0.809, p-value = 0.011).

Conclusion

RDT is a reliable source of DNA for P. falciparum detection and genotyping assays. Furthermore, the increasing use of RDTs allows them to be an alternative source of DNA for large-scale genetic epidemiological studies. Parasite populations in the study area are highly diverse and prevalence of chloroquine-resistant P. falciparum remains high, especially in rural areas.

Accuracy, Ease of Use, Safety, and Acceptability of a 23-μL Conical Cup Blood Transfer Device for Use with Rapid Diagnostic Tests

Devices to safely transfer fixed amounts of finger prick blood to rapid diagnostic tests (RDTs) pose a significant challenge, especially in non-laboratory settings. Following the success of an “inverted cup device” for transfer of 5 μL blood, a prototype with a conical cup shape was developed for transfer of 20 μL blood, the amount needed for human immunodeficiency virus or human African trypanosomiasis (HAT) RDTs. This study determined the volume of blood transferred by this new blood transfer device (BTD) and compared its ease of use, safety, and acceptability with that of a plastic pipette when used by health workers (HWs) for HAT RDTs in northwestern Uganda. After a half-day training, 48 HWs had used the two BTDs with at least 10 patients. The conical cup BTD effectively transferred a mean of 22.76 μL of blood (standard deviation 3.31 μL). A significantly higher proportion of HWs were able to collect the full amount of blood using the conical cup BTD, as compared with the pipette (92.4% versus 74.2%, P < 0.001). In HW questionnaires, the conical cup BTD scored higher than the pipette in various aspects of ease of use and safety. In addition, HWs preferred the conical cup BTD (79%), indicating that it was easy to handle, made work faster, and increased their confidence in front of the patient. These findings suggest that the design of the conical cup BTD may be adapted for RDTs requiring 20 μL of blood to facilitate safe and accurate blood transfer.

Evaluation of malaria rapid diagnostic test (RDT) use by community health workers: a longitudinal study in western Kenya

Background

Malaria rapid diagnostic tests (RDTs) are a simple, point-of-care technology that can improve the diagnosis and subsequent treatment of malaria. They are an increasingly common diagnostic tool, but concerns remain about their use by community health workers (CHWs). These concerns regard the long-term trends relating to infection prevention measures, the interpretation of test results and adherence to treatment protocols. This study assessed whether CHWs maintained their competency at conducting RDTs over a 12-month timeframe, and if this competency varied with specific CHW characteristics.

Methods

From June to September, 2015, CHWs (n = 271) were trained to conduct RDTs using a 3-day validated curriculum and a baseline assessment was completed. Between June and August, 2016, CHWs (n = 105) were randomly selected and recruited for follow-up assessments using a 20-step checklist that classified steps as relating to safety, accuracy, and treatment; 103 CHWs participated in follow-up assessments. Poisson regressions were used to test for associations between error count data at follow-up and Poisson regression models fit using generalized estimating equations were used to compare data across time-points.

Results

At both baseline and follow-up observations, at least 80% of CHWs correctly completed 17 of the 20 steps. CHWs being 50 years of age or older was associated with increased total errors and safety errors at baseline and follow-up. At follow-up, prior experience conducting RDTs was associated with fewer errors. Performance, as it related to the correct completion of all checklist steps and safety steps, did not decline over the 12 months and performance of accuracy steps improved (mean error ratio: 0.51; 95% CI 0.40–0.63). Visual interpretation of RDT results yielded a CHW sensitivity of 92.0% and a specificity of 97.3% when compared to interpretation by the research team. None of the characteristics investigated was found to be significantly associated with RDT interpretation.

Conclusions

With training, most CHWs performing RDTs maintain diagnostic testing competency over at least 12 months. CHWs generally perform RDTs safely and accurately interpret results. Younger age and prior experiences with RDTs were associated with better testing performance. Future research should investigate the mode by which CHW characteristics impact RDT procedures.

Electronic supplementary material

The online version of this article (10.1186/s12936-018-2358-6) contains supplementary material, which is available to authorized users.

The inverted cup device for blood transfer on malaria RDTs: ease of use, acceptability and safety in routine use by health workers in Nigeria

BACKGROUND

Malaria rapid diagnostic tests (RDTs) are becoming widely adopted for case management at community level. However, reports and anecdotal observations indicate that the blood transfer step poses a significant challenge to many users. This study sought to evaluate the inverted cup device in the hands of health workers in everyday clinical practice, in comparison with the plastic pipette, and to determine the volume accuracy of the device made of a lower-cost plastic.

METHODS

The volume accuracy of inverted cup devices made of two plastics, PMMA and SBC, was compared by transferring blood 150 times onto filter paper and comparing the blood spot areas with those produced by 20 reference transfers with a calibrated micropipette. The ease of use, safety and acceptability of the inverted cup device and the pipette were evaluated by 50 health workers in Nigeria. Observations were recorded on pre-designed questionnaires, by the health workers themselves and by trained observers. Focus group discussions were also conducted.

RESULTS

The volume accuracy assessment showed that the device made from the low-cost material (SBC) delivered a more accurate volume (mean 5.4 μL, SD 0.48 μL, range 4.5-7.0 μL) than the PMMA device (mean 5.9 μL, SD 0.48 μL, range 4.9-7.2 μL). The observational evaluation demonstrated that the inverted cup device performed better than the pipette in all aspects, e.g. higher proportions of health workers achieved successful blood collection (96%, vs. 66%), transfer of the required blood volume (90%, vs. 58%), and blood deposit without any loss (95%, vs. 50%). Majority of health workers also considered it' very easy' to use (81%),'very appropriate' for everyday use (78%), and 50% of them reported that it was their preferred BTD.

CONCLUSIONS

The good volume accuracy and high acceptability of the inverted cup device shown in this study, along with observed ease of use and safety in hands of health workers, further strengthens prior findings which demonstrated its higher accuracy as compared with other BTDs in a laboratory setting. Altogether, these studies suggest that the inverted cup device should replace other types of devices for use in day-to-day malaria diagnosis with RDTs.

Quality issues with malaria rapid diagnostic test accessories and buffer packaging: findings from a 5-country private sector project in Africa

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.

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-017-1820-1) contains supplementary material, which is available to authorized users.

Multicenter Pivotal Clinical Trial of Urine Malaria Test for Rapid Diagnosis of Plasmodium falciparum Malaria

The need to expand malaria diagnosis capabilities alongside policy requirements for mandatory testing before treatment motivates exploration of noninvasive rapid diagnostic tests (RDTs). We report the outcome of the first cross-sectional, single-blind clinical performance evaluation of a urine malaria test (UMT) for diagnosis of Plasmodium falciparum malaria in febrile patients. Matched urine and finger-prick blood samples from participants ≥2 years of age with fever (axillary temperature of ≥37.5°C) or with a history of fever in the preceding 48 h were tested with UMT and microscopy (as the gold standard). BinaxNOW (Pf and Pan versions) blood RDTs were done to assess relative performance. Urinalysis and rheumatoid factor (RF) tests were conducted to evaluate possible interference. Diagnostic performance characteristics were computed at 95% confidence intervals (CIs). Of 1,800 participants screened, 1,691 were enrolled; of these 566 (34%) were febrile, and 1,125 (66%) were afebrile. Among enrolled participants, 341 (20%) tested positive by microscopy, 419 (25%) were positive by UMT, 676 (40%) were positive by BinaxNOW Pf, and 368 (22%) were positive by BinaxNow Pan. UMT sensitivity among febrile patients (for whom the test was indicated) was 85%, and specificity was 84%. Among febrile children ≤5 years of age, UMT sensitivity was 93%, and specificity was 83%. The area under the receiver-operator characteristic curve (AUC) of UMT (0.84) was not significantly different from that of BinaxNOW Pf (0.86) or of BinaxNOW Pan (0.87), indicating that the tests do not differ in overall performance. Gender, seasons, and RF did not impact UMT performance. Leukocytes, hematuria, and urobilinogen concentrations in urine were associated with lower UMT specificities. UMT performance was comparable to that of the BinaxNOW Pf/Pan tests, making UMT a promising tool to expand malaria testing in public and private health care settings where there are challenges to blood-based malaria diagnosis testing.

Performance of four HRP-2/pLDH combination rapid diagnostic tests and field microscopy as screening tests for malaria in pregnancy in Indonesia: a cross-sectional study

BACKGROUND

Malaria in pregnancy poses a major public health problem in Indonesia with an estimated six million pregnancies at risk of Plasmodium falciparum or Plasmodium vivax malaria annually. In 2010, Indonesia introduced a screen and treat policy for the control of malaria in pregnancy at first antenatal visit using microscopy or rapid diagnostic tests (RDTs). A diagnostic study was conducted in Sumba, Indonesia to compare the performance of four different RDTs in predominately asymptomatic pregnant women under field condition.

METHODS

Women were screened for malaria at antenatal visits using field microscopy and four HRP-2/pLDH combination RDTs (Carestart™, First-Response(®), Parascreen(®) and SD-Bioline(®)). The test results were compared with expert microscopy and nested PCR. End user experience of the RDTs in the field was assessed by questionnaire.

RESULTS

Overall 950 were recruited and 98.7 % were asymptomatic. The prevalence of malaria was 3.0-3.4 % by RDTs, and 3.6, 5.0 and 6.6 % by field microscopy, expert microscopy and PCR, respectively. The geometric-mean parasite density was low (P. falciparum = 418, P. vivax = 147 parasites/µL). Compared with PCR, the overall sensitivity of the RDTs and field microscopy to detect any species was 24.6-31.1 %; specificities were >98.4 %. Relative to PCR, First-Response(®) had the best diagnostic accuracy (any species): sensitivity = 31.1 %, specificity = 98.9 % and diagnostic odds ratio = 39.0 (DOR). The DOR values for Carestart™, Parascreen(®), SD-Bioline(®), and field microscopy were 23.4, 23.7, 23.5 and 29.2, respectively. The sensitivity of Pan-pLDH bands to detect PCR confirmed P. vivax mono-infection were 8.6-13.0 %. The sensitivity of the HRP-2 band alone to detect PCR confirmed P. falciparum was 10.3-17.9 %. Pan-pLDH detected P. falciparum cases undetected by the HRP-2 band resulting in a better test performance when both bands were combined. First Response(®) was preferred by end-users for the overall practicality.

CONCLUSION

The diagnostic accuracy to detect malaria among mostly asymptomatic pregnant women and perceived ease of use was slightly better with First-Response(®), but overall, differences between the four RDTs were small and performance comparable to field microscopy. Combination RDTs are a suitable alternative to field microscopy to screen for malaria in pregnancy in rural Indonesia. The clinical relevance of low density malaria infections detected by PCR, but undetected by RDTs or microscopy needs to be determined.

Design, implementation and evaluation of a training programme for school teachers in the use of malaria rapid diagnostic tests as part of a basic first aid kit in southern Malawi

Background

With increasing levels of enrolment, primary schools present a pragmatic opportunity to improve the access of school children to timely diagnosis and treatment of malaria, increasingly recognised as a major health problem within this age group. The expanded use of malaria rapid diagnostic tests (RDTs) and artemisinin combination therapy (ACT) by community health workers (CHWs) has raised the prospect of whether teachers can provide similar services for school children. We describe and evaluate the training of primary school teachers to use a first aid kit containing malaria RDTs and ACT for the diagnosis and treament of uncomplicated malaria in school children in southern Malawi.

Methods

We outline the development of the intervention as: (1) conception and design, (2) pilot training, (3) final training, and (4) 7-month follow up. The training materials were piloted at a four-day workshop in July 2013 following their design at national stakeholders meetings. The evaluation of the pilot training and materials were assessed in relation to increased knowledge and skill sets using checklist evaluations and questionnaires, the results of which informed the design of a final seven-day training programme held in December 2013. A follow up of trained teachers was carried out in July 2014 following 7 months of routine implementation. A total of 15 teachers were evaluated at four stages: pilot training, two weeks following pilot, final training and seven months following final training.

Results

A total of 15 and 92 teachers were trained at the pilot and final training respectively. An average of 93 % of the total steps required to use RDTs were completed correctly at the final training, declining to 87 % after 7 months. All teachers were observed correctly undertaking safe blood collection and handling, accurate RDT interpretation, and correct dispensing of ACT. The most commonly observed errors were a failure to wait 20 minutes before reading the test result, and adding an incorrect volume of buffer to the test cassette.

Conclusion

Following training, teachers are able to competently use RDTs and ACTs test and treat children at school for uncomplicated malaria safely and accurately. Teachers demonstrate a comparable level of RDT use relative to non-health professional users of RDTs, and sustain this competency over a period of seven months during routine implementation.

What should the ideal HIV self-test look like? A usability study of test prototypes in unsupervised HIV self-testing in Kenya, Malawi, and South Africa

HIV self-testing (HIVST) is increasingly being sought and offered globally, yet there is limited information about the test features that will be required for an HIV self-test to be easy to use, acceptable to users, and feasible for manufacturers to produce. We conducted formative usability research with participants who were naïve to HIVST using five prototypes in Kenya, Malawi, and South Africa. The tests selected ranged from early-stage prototypes to commercially ready products and had a diverse set of features. A total of 150 lay users were video-recorded conducting unsupervised self-testing and interviewed to understand their opinions of the test. Participants did not receive a test result, but interpreted standardized result panels. This study demonstrated that users will refer to the instructions included with the test, but these can be confusing or difficult to follow. Errors were common, with less than 25% of participants conducting all steps correctly and 47.3% of participants performing multiple errors, particularly in sample collection and transfer. Participants also had difficulty interpreting results. To overcome these issues, the ideal HIV self-test requires pictorial instructions that are easy to understand, simple sample collection with integrated test components, fewer steps, and results that are easy to interpret.

Community health workers use malaria rapid diagnostic tests (RDTs) safely and accurately: results of a longitudinal study in Zambia

Malaria rapid diagnostic tests (RDTs) could radically improve febrile illness management in remote and low-resource populations. However, reliance upon community health workers (CHWs) remains controversial because of concerns about blood safety and appropriate use of artemisinin combination therapy. This study assessed CHW ability to use RDTs safely and accurately up to 12 months post-training. We trained 65 Zambian CHWs, and then provided RDTs, job-aids, and other necessary supplies for village use. Observers assessed CHW performance at 3, 6, and 12 months post-training. Critical steps performed correctly increased from 87.5% at 3 months to 100% subsequently. However, a few CHWs incorrectly read faint positive or invalid results as negative. Although most indicators improved or remained stable over time, interpretation of faint positives fell to 76.7% correct at 12 months. We conclude that appropriately trained and supervised CHWs can use RDTs safely and accurately in community practice for up to 12 months post-training.

Blood transfer devices for malaria rapid diagnostic tests: evaluation of accuracy, safety and ease of use

BACKGROUND

Malaria rapid diagnostic tests (RDTs) are increasingly used by remote health personnel with minimal training in laboratory techniques. RDTs must, therefore, be as simple, safe and reliable as possible. Transfer of blood from the patient to the RDT is critical to safety and accuracy, and poses a significant challenge to many users. Blood transfer devices were evaluated for accuracy and precision of volume transferred, safety and ease of use, to identify the most appropriate devices for use with RDTs in routine clinical care.

METHODS

Five devices, a loop, straw-pipette, calibrated pipette, glass capillary tube, and a new inverted cup device, were evaluated in Nigeria, the Philippines and Uganda. The 227 participating health workers used each device to transfer blood from a simulated finger-prick site to filter paper. For each transfer, the number of attempts required to collect and deposit blood and any spilling of blood during transfer were recorded. Perceptions of ease of use and safety of each device were recorded for each participant. Blood volume transferred was calculated from the area of blood spots deposited on filter paper.

RESULTS

The overall mean volumes transferred by devices differed significantly from the target volume of 5 microliters (p < 0.001). The inverted cup (4.6 microliters) most closely approximated the target volume. The glass capillary was excluded from volume analysis as the estimation method used is not compatible with this device. The calibrated pipette accounted for the largest proportion of blood exposures (23/225, 10%); exposures ranged from 2% to 6% for the other four devices. The inverted cup was considered easiest to use in blood collection (206/226, 91%); the straw-pipette and calibrated pipette were rated lowest (143/225 [64%] and 135/225 [60%] respectively). Overall, the inverted cup was the most preferred device (72%, 163/227), followed by the loop (61%, 138/227).

CONCLUSIONS

The performance of blood transfer devices varied in this evaluation of accuracy, blood safety, ease of use, and user preference. The inverted cup design achieved the highest overall performance, while the loop also performed well. These findings have relevance for any point-of-care diagnostics that require blood sampling.

Improving rational treatment of malaria: perceptions and influence of RDTs on prescribing behaviour of health workers in southeast Nigeria

INTRODUCTION

Developments in rapid diagnostic tests (RDTs) have opened new possibilities for improved remote malaria diagnosis that is independent of microscopic diagnosis. Studies in some settings have tried to assess the influence of RDTs on the prescribing behaviour of health workers, but such information is generally lacking in Nigeria and many parts of sub-Saharan Africa. This study analysed health workers' perceptions of RDTs and their potential influence on their prescribing and treatment practices after their introduction.

METHODS

The study was conducted in four health centers in the Enugu East local government of Enugu State, Nigeria. All 32 health workers in the health centers where RDTs were deployed were interviewed by field workers. Information was sought on their perception of symptoms-based, RDT-based, and microscopy-based malaria diagnoses. In addition, prescription analysis was carried out on 400 prescriptions before and 12 months after RDT deployment.

RESULTS

The majority of the health workers perceived RDTs to be more effective for malaria diagnosis than microscopy and clinical diagnosis. They also felt that the benefits of RDTs included increased use of RDTs in the facilities and the tendency to prescribe more Artemisinin-based combination therapies (ACTs) and less chloroquine and SP. Some of the health workers experienced some difficulties in the process of using RDT kits. ACTs were prescribed in 74% of RDT-negative results.

CONCLUSIONS/SIGNIFICANCE

RDT-supported malaria diagnosis may have led to the overprescription of ACTs, with the drug being prescribed to people with RDT-negative results. However, the prescription of other antimalarial drugs that are not first-line drugs has been reduced. Efforts should be made to encourage health workers to trust RDT results and prescribe ACTs only to those with positive RDT results. In-depth studies are needed to determine why health workers continue to prescribe ACTs in RDT-negative results.

External quality assessment on the use of malaria rapid diagnostic tests in a non-endemic setting

Background

Malaria rapid diagnostic tests (RDTs) are increasingly used as a tool for the diagnosis of malaria, both in endemic and in non-endemic settings. The present study reports the results of an external quality assessment (EQA) session on RDTs in a non-endemic setting.

Methods

After validation of antigen stability during shipment at room temperature, three clinical samples and a questionnaire were sent to clinical laboratories in Belgium and the Grand Duchy of Luxembourg using malaria RDTs. Participants were asked to report the results of the RDTs as observations (visibility of the RDT control and test lines) and interpretations (report as formulated to the clinician). In addition, participants were invited to fill in a questionnaire on the place of RDTs in the diagnostic strategy of malaria.

Results

A total of 128/133 (96.2%) of clinical laboratories using RDTs participated. Six three-band and one four-band RDT brands were used. Analytical errors were rare and included (i) not recognizing invalid RDT results (1.6%) and (ii) missing the diagnosis of Plasmodium falciparum (0.8%). Minor errors were related to RDT test result interpretation and included (i) reporting "RDT positive" without species identification in the case of P. falciparum and non-falciparum species (16.9% and 6.5% respectively) and (ii) adding incorrect comments to the report (3.2%). Some of these errors were related to incorrect RDT package insert instructions such as (i) not reporting the possibility of mixed species infection in the case of P. falciparum and Plasmodium vivax (35.5% and 18.5% respectively) and (ii) the interpretation of P. vivax instead of non-falciparum species at the presence of a pan-species antigen line (4.0%). According to the questionnaire, 48.8% of participants processed ≤20 requests for malaria diagnosis in 2009. During opening hours, 93.6% of 125 participants used RDTs as an adjunct to microscopy but outside opening hours, nearly one third of 113 participants relied on RDTs as the primary (4.4%) or the single tool (25.7%) for malaria diagnosis.

Conclusion

In this non-endemic setting, errors in RDT performance were mainly related to RDT test line interpretations, partly due to incorrect package insert instructions. The reliance on RDTs as the primary or the single tool for the diagnosis of malaria outside opening hours is of concern and should be avoided.

Examining appropriate diagnosis and treatment of malaria: availability and use of rapid diagnostic tests and artemisinin-based combination therapy in public and private health facilities in south east Nigeria

Background

Rapid diagnostic tests (RDTs) and Artemisinin-based combination therapy (ACT) have been widely advocated by government and the international community as cost-effective tools for diagnosis and treatment of malaria. ACTs are now the first line treatment drug for malaria in Nigeria and RDTs have been introduced by the government to bridge the existing gaps in proper diagnosis. However, it is not known how readily available these RDTs and ACTs are in public and private health facilities and whether health workers are actually using them. Hence, this study investigated the levels of availability and use of RDTs and ACTs in these facilities.

Methods

The study was undertaken in Enugu state, southeast Nigeria in March 2009. Data was collected from heads of 74 public and private health facilities on the availability and use of RDTs and ACTs. Also, the availability of RDTs and the types of ACTs that were available in the facilities were documented.

Results

Only 31.1% of the health facilities used RDTs to diagnose malaria. The majority used the syndromic approach. However, 61.1% of healthcare providers were aware of RDTs. RDTs were available in 53.3% of the facilities. Public health facilities and health facilities in the urban areas were using RDTs more and these were mainly bought from pharmacy shops and supplied by NGOs. The main reasons given for non use are unreliability of RDTs, supply issues, costs, preference for other methods of diagnosis and providers' ignorance. ACTs were the drug of choice for most public health facilities and the drugs were readily available in these facilities.

Conclusion

Although many providers were knowledgeable about RDTs, not many facilities used it. ACTS were readily available and used in public but not private health facilities. However, the reported use of ACTs with limited proper diagnosis implies that there could be high incidence of inappropriate case management of malaria which can also increase the economic burden of illnesses. Government and donors should ensure constant availability of RDTs in both public and private facilities, so that every treatment with ACTs is accompanied with proper diagnosis.

Improving community health worker use of malaria rapid diagnostic tests in Zambia: package instructions, job aid and job aid-plus-training

Background

Introduction of artemisinin combination therapy (ACT) has boosted interest in parasite-based malaria diagnosis, leading to increased use of rapid diagnostic tests (RDTs), particularly in rural settings where microscopy is limited. With donor support, national malaria control programmes are now procuring large quantities of RDTs. The scarcity of health facilities and trained personnel in many sub-Saharan African countries means that limiting RDT use to such facilities would exclude a significant proportion of febrile cases. RDT use by volunteer community health workers (CHWs) is one alternative, but most sub-Saharan African countries prohibit CHWs from handling blood, and little is known about CHW ability to use RDTs safely and effectively. This Zambia-based study was designed to determine: (i) whether Zambian CHWs could prepare and interpret RDTs accurately and safely using manufacturer's instructions alone; (ii) whether simple, mostly pictorial instructions (a "job aid") could raise performance to adequate levels; and (iii) whether a brief training programme would produce further improvement.

Methods

The job aid and training programme were based on formative research with 32 CHWs in Luangwa District. The study team then recruited three groups of CHWs in Chongwe and Chibombo districts. All had experience treating malaria based on clinical diagnosis, but only six had prior RDT experience. Trained observers used structured observation checklists to score each participant's preparation of three RDTs. Each also read 10 photographs showing different test results. The first group (n = 32) was guided only by manufacturer's instructions. The second (n = 21) used only the job aid. The last (n = 26) used the job aid after receiving a three-hour training.

Results

Mean scores, adjusted for education, age, gender and experience, were 57% of 16 RDT steps correctly completed for group 1, 80% for group 2, and 92% for group 3. Mean percentage of test results interpreted correctly were 54% (group 1), 80% (group 2), and 93% (group 3). All differences were statistically significant (p < 0.05).

Conclusion

Manufacturer's instructions like those provided with the RDTs used in this study are insufficient to ensure safe and accurate use by CHWs. However, well-designed instructions plus training can ensure high performance. More study is underway to determine how well this performance holds up over time.