HIV Rapid Diagnostic Tests Research Articles

Should trained lay providers perform HIV testing? A systematic review to inform World Health Organization guidelines

ABSTRACTNew strategies for HIV testing services (HTS) are needed to achieve UN 90-90-90 targets, including diagnosis of 90% of people living with HIV. Task-sharing HTS to trained lay providers may alleviate health worker shortages and better reach target groups. We conducted a systematic review of studies evaluating HTS by lay providers using rapid diagnostic tests (RDTs). Peer-reviewed articles were included if they compared HTS using RDTs performed by trained lay providers to HTS by health professionals, or to no intervention. We also reviewed data on end-users’ values and preferences around lay providers preforming HTS. Searching was conducted through 10 online databases, reviewing reference lists, and contacting experts. Screening and data abstraction were conducted in duplicate using systematic methods. Of 6113 unique citations identified, 5 studies were included in the effectiveness review and 6 in the values and preferences review. One US-based randomized trial found patients’ uptake of HTS doubled with lay providers (57% vs. 27%, percent difference: 30, 95% confidence interval: 27-32, p < 0.001). In Malawi, a pre/post study showed increases in HTS sites and tests after delegation to lay providers. Studies from Cambodia, Malawi, and South Africa comparing testing quality between lay providers and laboratory staff found little discordance and high sensitivity and specificity (≥98%). Values and preferences studies generally found support for lay providers conducting HTS, particularly in non-hypothetical scenarios. Based on evidence supporting using trained lay providers, a WHO expert panel recommended lay providers be allowed to conduct HTS using HIV RDTs. Uptake of this recommendation could expand HIV testing to more people globally.

Evaluation of the performances of twelve rapid diagnostic tests for diagnosis of HIV infection in Yaounde, Cameroon

According to the WHO/UNAIDS recommendations, an acceptable HIV rapid diagnostic tests (RDTs) has to perform a sensitivity≥99% and a specificity≥98%. Given the constant release of new RDTs for HIV testing in the market and the high HIV genetic diversity in Cameroon, it is interesting to monitor their performances in that setting.A total of 240 HIV positive (including 219 HIV-1 M, 15 HIV-1 O, 1 HIV-1 N, 1 HIV-1 M/O recombinant and 4 HIV-2) and 240 HIV negative plasma samples were used to evaluate twelve routinely used RDTs in Cameroon. A reference algorithm combining Enzyme Immunoassays and nucleic acid testing was used as gold standard.The sensitivity, specificity, positive predictive value, and negative predictive value of the twelve RDTs evaluated varied between 93.7 and 100%; 95.8 and 100%; 96.0 and 100%, and 94.1 and 100%, respectively. Five out of the twelve RDTs could not detect some HIV-1 O variants, one of them failed to detect an HIV-2 variant while all them efficiently detected HIV-1 N and HIV M/O recombinant.Our findings underscore the need to monitor the performances of RDTs to be used for HIV testing in Cameroon using locally obtained well-characterized samples panels.

An Evaluation of Selected Populations for HIV-1 Vaccine Cohort Development in Nigeria.

Development of a globally effective HIV-1 vaccine will need to encompass Nigeria, one of the hardest hit areas, with an estimated 3.2 million people living with HIV. This cross-sectional Institutional Review Board (IRB) approved study was conducted in 2009–12 at four market sites and two highway settlements sites in Nigeria to identify and characterize populations at high risk for HIV; engage support of local stakeholders; and assess the level of interest in future vaccine studies. Demographic, HIV risk data were collected by structured interviewer-administered questionnaires. Blood samples were tested on site by HIV rapid diagnostic tests, followed by rigorous confirmatory testing, subtype evaluation and testing for HBV and HCV markers in a clinical reference laboratory. Of 3229 study participants, 326 were HIV infected as confirmed by Western Blot or RNA, with a HIV prevalence of 15.4%-23.9% at highway settlements and 3.1%-9.1% at market sites. There was no observable correlation of prevalence of HIV-1 (10.1%) with HBV (10.9%) or HCV (2.9%). Major HIV-1 subtypes included CRF02_AG (37.5%); G (27.5%); G/CRF02_AG (25.9%); and non-typeable (8.9%), with 0.3% HIV-2. Univariate analysis found age, gender, marital status, level of education, and sex under substance influence as significant risk factors for HIV (p<0.001). Educating and winning the trust of local community leadership ensured high level of participation (53.3–77.9%) and willingness to participate in future studies (95%). The high HIV prevalence and high risk of HIV infection at highway settlement and mammy markets make them well suited for targeting future vaccine trials in Nigeria.

Acceptability of malaria rapid diagnostic tests administered by village health workers in Pangani District, North eastern Tanzania.

BackgroundMalaria continues to top the list of the ten most threatening diseases to child survival in Tanzania. The country has a functional policy for appropriate case management of malaria with rapid diagnostic tests (RDTs) from hospital level all the way to dispensaries, which are the first points of healthcare services in the national referral system. However, access to these health services in Tanzania is limited, especially in rural areas. Formalization of trained village health workers (VHWs) can strengthen and extend the scope of public health services, including diagnosis and management of uncomplicated malaria in resource-constrained settings. Despite long experience with VHWs in various health interventions, Tanzania has not yet formalized its involvement in malaria case management. This study presents evidence on acceptability of RDTs used by VHWs in rural northeastern Tanzania.MethodsA cross-sectional study using quantitative and qualitative approaches was conducted between March and May 2012 in Pangani district, northeastern Tanzania, on community perceptions, practices and acceptance of RDTs used by VHWs.ResultsAmong 346 caregivers of children under 5 years old, no evidence was found of differences in awareness of HIV rapid diagnostic tests and RDTs (54 vs. 46 %, p = 0.134). Of all respondents, 92 % expressed trust in RDT results, 96 % reported readiness to accept RDTs by VHWs, while 92 % expressed willingness to contribute towards the cost of RDTs used by VHWs. Qualitative results matched positive perceptions, attitudes and acceptance of mothers towards the use of RDTs by VHWs reported in the household surveys. Appropriate training, reliable supplies, affordability and close supervision emerged as important recommendations for implementation of RDTs by VHWs.ConclusionRDTs implemented by VHWs are acceptable to rural communities in northeastern Tanzania. While families are willing to contribute towards costs of sustaining these services, policy decisions for scaling-up will need to consider the available and innovative lessons for successful universally accessible and acceptable services in keeping with national health policy and sustainable development goals.

Laboratory Innovation Towards Quality Program Sustainability.

Laboratory innovation significantly affects program sustainability of HIV programs in low and middle income countries (LMICs) far beyond its immediate sphere of impact. Innovation in rapid development of diagnostic technologies, improved quality management systems, strengthened laboratory management, affordable external quality assurance and accreditation schemes, and building local capacity have reduced costs, brought quality improvement to point-of-care testing, increased access to testing services, reduced treatment and prevention costs and opened the door to the real possibility of ending the AIDS epidemic. However, for effectively implemented laboratory innovation to contribute to HIV quality program sustainability, it must be implemented within the overall context of the national strategic plan and HIV treatment programs. The high quality of HIV rapid diagnostic test was a breakthrough that made it possible for more persons to learn their HIV status, receive counseling, and if infected to receive treatment. Likewise, the use of dried blood spots made the shipment of samples easier for the assessment of different variables of HIV infection-molecular diagnosis, CD4+ cell counts, HIV antibodies, drug resistance surveillance, and even antiretroviral drug level measurements. Such advancement is critical for to reaching the UNAIDS target of 90-90-90 and for bringing the AIDS epidemic to an end, especially in LMICs.

HIV Self-Testing, Self-Stigma and Haart Treatment at the University of Limpopo: Health Sciences Students' Opinion and Perspectives.

HIV self-testing (HIVST) is an empowering process in which an individual performs an HIV rapid diagnostic test and interprets the result in privacy. Policy makers have turned to it to facilitate greater uptake, earlier diagnosis, access to prevention, care and treatment services. The University of Limpopo now has an established HIV counselling and testing (HCT) service. Unfortunately, the uptake of this HCT service by the student body is not encouraging.It was against this background that a study was carried out among health sciences students, to assess the potential of HIVST to increase access to and uptake of HIV testing on campus. Information was gathered through focus group discussions and the social media Whatspp, among 300 health sciences students, to provide a ‘yes’ or ‘no’ response to an enquiry, about HIVST and the pregnancy test. One on one discussion on the same issues was also held with the staff at the student Health Centre which now stocks ARVs.About 51% of the students, the majority being females indicated that they would go for the HIVST. Students’ opinion and perspectives appeared to suggest that there was a potential for the HIVST to increase uptake for HIV testing.

Editorial: HIV Infection and AIDS in Africa - Issues, Lessons Learnt and Next Steps.

Editorial: HIV Infection and AIDS in Africa - Issues, Lessons Learnt and Next Steps.

Perinatal HIV Status and Executive Function During School-Age and Adolescence: A Comparative Study of Long-Term Cognitive Capacity Among Children From a High HIV Prevalence Setting.

The aim of this study was to determine whether perinatal HIV infection (PHIV), HIV-exposed uninfected (PHEU) versus HIV-unexposed (PHU) status predicted long-term executive function (EF) deficit in school-aged Ugandan children.Perinatal HIV status was determined by 18 months via DNA polymerase chain reaction test and confirmed at cognitive assessment between 6 and 18 years using HIV rapid-diagnostic test. Primary outcome is child EF measured using behavior-rating inventory of executive function questionnaire across 8 subscales summed to derive the global executive composite (GEC). EF was proxy-reported by caregivers and self-reported by children 11 years or older. Descriptive analyses by perinatal HIV status included derivation of mean, standard deviations (SD), number, and percent (%) of children with EF deficits warranting clinical vigilance. Raw scores were internally standardized by age and sex adjustment. EF scores warranting clinical vigilance were defined as ≥ mean + 1.5SD. t Tests for mean score differences by perinatal HIV status and linear-regression models were implemented in SAS version 9.4 to derive HIV status-related EF deficits (β) and 95% confidence intervals (CIs).Proxy-reported and self-reported EF were assessed in 166 and 82 children, respectively. GEC deficit was highest for PHIV (mean = 121.9, SD = 29.9), intermediate for PHEU (mean = 107.5, SD = 26.8), and lowest for PHU (mean = 103.4, SD = 20.7; P-trend < 0.01). GEC deficit levels warranting clinical vigilance occurred in 9 (15.8%), 5 (9.3%) and 0 (0%) PHIV, PHEU, and PHU children, respectively (P-trend = 0.01). Nineteen percent (n = 32) children had deficits requiring clinical vigilance in ≥2 proxy-reported EF subscales. Of these, multisubscale deficits occurred in 35.1%, 13.0%, and 9.3% of PHIV, PHEU, and PHU respectively (P-trend = 0.001). Multivariable analyses find significantly higher GEC deficits for PHIV compared with PHU and PHEU children regardless of respondent (all P values <0.01). Proxy-reported EF performance was similar for PHEU compared with PHU; however, child self-reported GEC scores were elevated by 12.8 units (95% CI: 5.4-25.5) for PHEU compared with PHU.PHIV had long-term EF deficits compared with other groups. Furthermore, PHEU ≥11 years may have long-term EF deficits compared with PHU, but future studies are needed to clarify this relationship. Cognitive remediation interventions with emphasis on EF may translate to improvements in long-term functional survival in HIV-affected children from sub-Saharan Africa.

Laboratory evaluation of the Chembio Dual Path Platform HIV-Syphilis Assay.

BackgroundUse of rapid diagnostic tests for HIV and syphilis has increased remarkably in the last decade. As new rapid diagnostic tests become available, there is a continuous need to assess their performance and operational characteristics prior to use in clinical settings.ObjectivesIn this study, we evaluated the performance of the Chembio Dual Path Platform (DPP®) HIV–Syphilis Assay to accurately diagnose HIV, syphilis, and HIV/syphilis co-infection.MethodIn 2013, 990 serum samples from the Georgia Public Health Laboratory in Atlanta, Georgia, United States were characterised for HIV and syphilis and used to evaluate the platform. HIV reference testing combined third-generation Enzyme Immunoassay and Western Blot, whereas reference testing for syphilis was conducted by the Treponema pallidum passive particle agglutination method and the TrepSure assay. We assessed the sensitivity and specificity of the DPP assay on this panel by comparing results with the HIV and syphilis reference testing algorithms.ResultsFor HIV, sensitivity was 99.8% and specificity was 98.4%; for syphilis, sensitivity was 98.8% and specificity was 99.4%. Of the 348 co-infected sera, 344 (98.9%) were detected accurately by the DPP assay, but 11 specimens had false-positive results (9 HIV and 2 syphilis) due to weak reactivity.ConclusionIn this evaluation, the Chembio DPP HIV–Syphilis Assay had high sensitivity and specificity for detecting both HIV and treponemal antibodies. Our results indicate that this assay could have a significant impact on the simultaneous screening of HIV and syphilis using a single test device for high-risk populations or pregnant women needing timely care and treatment.

Psychosocial adjustment in perinatally human immunodeficiency virus infected or exposed children - a Retrospective Cohort Study.

ObjectiveTo determine whether perinatal HIV infection and exposure adversely affected psychosocial adjustment (PA) between 6 and 18 years of life (i.e. during school-age and adolescence).MethodsWe enrolled 58 perinatally HIV-infected, 56 HIV-exposed uninfected and 54 unexposed controls from Kampala, Uganda. Perinatal HIV status was determined by 18 months of age using a DNA-polymerase chain-reaction test and was confirmed via HIV rapid diagnostic test at psychosocial testing when the children were 6 to 18 years old. Five indicators of PA (depressive symptoms, distress, hopelessness, positive future orientation and esteem) were measured using validated, culturally adapted and translated instruments. Multivariable linear regression analyses estimated HIV-status-related percent differences (β) in PA indicators and corresponding 95% confidence intervals (CIs).ResultsDuring school-age and adolescence, positive outlook (β=−3.8, 95% CI: −7.2, −0.1) and self-esteem (β=−4.3, 95% CI: −6.7, −1.8) scores were significantly lower, whereas depressive (β=11.4, 95% CI: 3.3, 19.5) and distress (β=12.3, 95% CI: 5.9, 18.7) symptoms were elevated for perinatally HIV-infected, compared to unexposed controls and exposed uninfected children. Similarly, positive outlook (β=−4.3, 95% CI: −7.3, −1.2) and self-esteem were lower for exposed controls versus HIV-unexposed children. Hopelessness was similar by perinatal HIV status. Likewise, the distress and depressive symptom levels were comparable for HIV-exposed uninfected and HIV-unexposed children.ConclusionsPerinatal HIV infection predicted higher distress and depressive symptoms, while HIV-affected status (infection/exposure) predicted low self-esteem and diminished positive outlook in the long term. However, HIV-affected status had no impact on hopelessness, suggesting that psychosocial interventions as an integral component of HIV care for infected children or primary care exposed uninfected children may improve PA and quality of life in these vulnerable groups.

Rapid HIV test in family practice

BackgroundThe 2010-2014 HIV/AIDS French program recommends using HIV rapid diagnostic tests in family practice. Our aim was to assess the acceptability and feasibility of the RDT in family practice in France. MethodsThe first part of this study was to determine the opinions of family practitioners (FPs) concerning the news guidelines for screening and the possible use of rapid HIV tests in their practice. The second part was a feasibility study of the actual use of rapid HIV tests given to FPs during six months. The third part was a qualitative analysis of experience feedback to determine the impediments to using rapid HIV tests. ResultsSeventy-seven percent of the 352 FPs interviewed were favorable to rapid HIV tests use. The three main impediments were: misinterpretation of test result, complexity of quality control, and lack of training: 23 of the 112 FPs having volunteered to evaluate the rapid HIV tests followed the required training session. Sixty-nine tests were handed out, and three rapid HIV tests were used; the qualitative study involved 12 FPs. The participants all agreed on the difficult use of rapid HIV tests in daily practice. The main reasons were: too few opportunities or requests for use, complex handling, difficulties in proposing the test, fear of having to announce seropositivity, significantly longer consultation. ConclusionAlthough FPs are generally favorable to rapid HIV tests use in daily practice, the feasibility and contribution of rapid HIV tests are limited in family practice.

Laboratory evaluation of three dual rapid diagnostic tests for HIV and syphilis in China and Nigeria

ObjectiveTo determine the laboratory-based performance and operational characteristics of three dual rapid diagnostic tests (RDTs) for testing HIV and syphilis. MethodsThree dual RDTs (SD Bioline, Chembio, and MedMira) were evaluated using 1514 serum specimens archived at laboratories or collected from clinics in China and Nigeria to determine sensitivity and specificity, with 95% confidence intervals. Concordance of testing results read by two technicians, stability of testing results read at two time points, and test operation characteristics were also assessed. ResultsAll three of the evaluated RDTs gave excellent performance with a combined sensitivity ranging from 99.0%–99.6% for HIV and 98.3%–99.0% for syphilis, and a combined specificity ranging from 97.9%–99.0% for HIV and 97.2%–99.6% for syphilis. Concordance of testing results between two technicians and stability of testing results read within and one hour past the recommended reading period showed excellent agreement, with Kappa greater than or equal to 0.98. ConclusionsAll the tests were found to be very or fairly easy to use and easy to interpret the results. Further evaluations of these dual RDTs with whole blood in field settings, and more studies on the implication of introduction of these tests in HIV and syphilis control programs are needed.

The Potential for HIV Self-testing in Iran.

an HIV rapid diagnostic test and interprets the test result.[9‐11] HIVST is an emerging approach that is both well‐accepted and potentially cost‐effective. It has a potential to facilitate further uptake of HIV testing particularly in high risk population.[9] Other potential benefits of HIVST are less resource intensive with respect to the healthcare system, it empowers users, thus helping to normalize testing, reduce stigmatization, increases patients autonomy and mutual partner testing.[6] HIVST could provide convenient and anonymous HIV testing to anyone who wants to do testing. In particular, depending on cost and availability, self‐tests can benefit people who experience significant barriers to health care and people living in rural and remote communities where health care isn’t always anonymous or confidential.

1581Laboratory Evaluation of three HIV and Syphilis Combination Rapid Diagnostic Tests

1581Laboratory Evaluation of three HIV and Syphilis Combination Rapid Diagnostic Tests

Uptake of HIV Self-testing among People Receiving PrEP in Kenya

AIDS Research and Human RetrovirusesVol. 30, No. S1 PrEP: Self-testing, Safety and ModelingUptake of HIV Self-testing among People Receiving PrEP in KenyaKenneth Ngure, Renee Heffron, Nelly Mugo, Elizabeth Irungu, Njambi Njuguna, Lawrence Mwaniki, Kerry Thompson, Connie Celum, and Jared M. BaetenKenneth NgureJomo Kenyatta University of Agriculture and Technology, Nairobi, KenyaUniversity of Washington, Global Health, Seattle, WA, United StatesSearch for more papers by this author, Renee HeffronUniversity of Washington, Global Health, Seattle, WA, United StatesSearch for more papers by this author, Nelly MugoUniversity of Washington, Global Health, Seattle, WA, United StatesKenya Medical Research Institute, Center for Clinical Research, Nairobi, KenyaSearch for more papers by this author, Elizabeth IrunguPartners in Health Research and Development, Thika, KenyaSearch for more papers by this author, Njambi NjugunaPartners in Health Research and Development, Thika, KenyaSearch for more papers by this author, Lawrence MwanikiPartners in Health Research and Development, Thika, KenyaSearch for more papers by this author, Kerry ThompsonUniversity of Washington, Seattle, WA, United StatesSearch for more papers by this author, Connie CelumUniversity of Washington, Global Health, Seattle, WA, United StatesUniversity of Washington, Epidemiology, Seattle, WA, United StatesUniversity of Washington, Medicine, Seattle, WA, United StatesSearch for more papers by this author, and Jared M. BaetenUniversity of Washington, Global Health, Seattle, WA, United StatesUniversity of Washington, Epidemiology, Seattle, WA, United StatesUniversity of Washington, Medicine, Seattle, WA, United StatesSearch for more papers by this authorPublished Online:30 Oct 2014https://doi.org/10.1089/aid.2014.5128.abstractAboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View article"Uptake of HIV Self-testing among People Receiving PrEP in Kenya." AIDS Research and Human Retroviruses, 30(S1), p. A70FiguresReferencesRelatedDetailsCited byReliability of HIV rapid diagnostic tests for self-testing compared with testing by health-care workers: a systematic review and meta-analysisThe Lancet HIV, Vol. 5, No. 6Uptake and Acceptability of Oral HIV Self-Testing among Community Pharmacy Clients in Kenya: A Feasibility Study26 January 2017 | PLOS ONE, Vol. 12, No. 1 Volume 30Issue S1Oct 2014 InformationCopyright 2014, Mary Ann Liebert, Inc.To cite this article:Kenneth Ngure, Renee Heffron, Nelly Mugo, Elizabeth Irungu, Njambi Njuguna, Lawrence Mwaniki, Kerry Thompson, Connie Celum, and Jared M. Baeten.Uptake of HIV Self-testing among People Receiving PrEP in Kenya.AIDS Research and Human Retroviruses.Oct 2014.A70-A70.http://doi.org/10.1089/aid.2014.5128.abstractPublished in Volume: 30 Issue S1: October 30, 2014PDF download

Variation in Specificity of HIV Rapid Diagnostic Tests over Place and Time: An Analysis of Discordancy Data Using a Bayesian Approach

BackgroundRecent trends to earlier access to anti-retroviral treatment underline the importance of accurate HIV diagnosis. The WHO HIV testing strategy recommends the use of two or three rapid diagnostic tests (RDTs) combined in an algorithm and assume a population is serologically stable over time. Yet RDTs are prone to cross reactivity which can lead to false positive or discordant results. This paper uses discordancy data from Médecins Sans Frontières (MSF) programmes to test the hypothesis that the specificity of RDTs change over place and time. MethodsData was drawn from all MSF test centres in 2007-8 using a parallel testing algorithm. A Bayesian approach was used to derive estimates of disease prevalence, and of test sensitivity and specificity using the software WinBUGS. A comparison of models with different levels of complexity was performed to assess the evidence for changes in test characteristics by location and over time. Results106, 035 individuals were included from 51 centres in 10 countries using 7 different RDTs. Discordancy patterns were found to vary by location and time. Model fit statistics confirmed this, with improved fit to the data when test specificity and sensitivity were allowed to vary by centre and over time. Two examples show evidence of variation in specificity between different testing locations within a single country. Finally, within a single test centre, variation in specificity was seen over time with one test becoming more specific and the other less specific.ConclusionThis analysis demonstrates the variable specificity of multiple HIV RDTs over geographic location and time. This variability suggests that cross reactivity is occurring and indicates a higher than previously appreciated risk of false positive HIV results using the current WHO testing guidelines. Given the significant consequences of false HIV diagnosis, we suggest that current testing and evaluation strategies be reviewed.

Willingness to use a rapid diagnostic test for malaria in a rural area of central Côte d’Ivoire

BackgroundMalaria mortality is mainly a direct consequence of inadequate and/or delayed diagnosis and case management. Some important control interventions (e.g. long-lasting insecticidal nests) have contributed to reduce malaria morbidity and mortality in different parts of the world. Moreover, the development and effective use of rapid diagnostic tests (RDTs) hold promise to further enhance the control and elimination of malaria, particularly in areas where health services are deficient. The aim of this study was to determine knowledge, attitudes, practices and beliefs in relation to RDTs for malaria in rural Côte d’Ivoire.MethodsOne hundred individuals from Bozi and Yoho who sought care at the health centre in Bozi and were offered an RDT for malaria were interviewed in April 2010 using a pre-tested questionnaire on practice and perceptions in relation to RDTs for malaria. The relationships between acceptance of RDTs and factors related to opinions were identified, using generalized linear mixed models. Qualitative data from open-ended questions complemented the quantitative analysis.ResultsOnly 34 out of 100 patients who were offered an RDT for malaria were willing to undergo the test. People who perceived blood as a sacred body fluid were less likely to comply with an RDT. The concurrent availability and use of RDTs for HIV and malaria was associated with an unwilling attitude towards RDTs for malaria (Fisher’s exact test, p <0.001). The initial willingness of patients to accept malaria testing with RDTs was significantly related to general fear and wanting to know malaria infection status. For further and regular use of RDTs, a strong relationship was observed between acceptance and the idea that an RDT is a pretext used by health worker to know HIV status (odds ratio (OR) = 16.61, 95% confidence interval (CI) = 1.03-268.5). Those thinking that blood samples were useful for medical diagnoses were 8.31-times (95% CI = 2.22-31.1) more likely to undergo an RDT compared to those rejecting blood sampling as a diagnostic strategy.ConclusionSocio-cultural factors might be barriers for accepting RDTs in general health services. There are social representations of malaria and HIV/AIDS, symbolic for blood or experiences in relation to blood taking and blood-related diseases in relation to the introduction and routine use of RDTs. Special attention should be given to these barriers as otherwise the promotion of RDTs for prompt and effective diagnosis and subsequent management of malaria is hampered.

Assessment of desiccants and their instructions for use in rapid diagnostic tests

BackgroundMalaria rapid diagnostic tests (RDTs) are protected from humidity-caused degradation by a desiccant added to the device packaging. The present study assessed malaria RDT products for the availability, type and design of desiccants and their information supplied in the instructions for use (IFU).MethodsCriteria were based on recommendations of the World Health Organization (WHO), the European Community (CE) and own observations. Silica gel sachets were defined as self-indicating (all beads coated with a humidity indicator that changes colour upon saturation), partial-indicating (part of beads coated) and non-indicating (none of the beads coated). Indicating silica gel sachets were individually assessed for humidity saturation and (in case of partial-indicating silica gels) for the presence of indicating beads.ResultsFifty malaria RDT products from 25 manufacturers were assessed, 14 (28%) products were listed by the “Global Fund Quality Assurance Policy” and 31 (62%) were CE-marked. All but one product contained a desiccant, mostly (47/50, 94%) silica gel. Twenty (40%) RDT products (one with no desiccant and 19 with non-indicating desiccant) did not meet the WHO guidelines recommending indicating desiccant. All RDT products with self- or partial-indicating silica gel (n = 22 and 8 respectively) contained the toxic cobalt dichloride as humidity indicator. Colour change indicating humidity saturation was observed for 8/16 RDT products, at a median incidence of 0.8% (range 0.05%-4.6%) of sachets inspected. In all RDTs with partial-indicating silica gel, sachets with no colour indicating beads were found (median proportion 13.5% (0.6% - 17.8%) per product) and additional light was needed to assess the humidity colour. Less than half (14/30, 47%) IFUs of RDT products with indicating desiccants mentioned to check the humidity saturation before using the test. Information on properties, safety hazards and disposal of the desiccant was not included in any of the IFUs. There were no differences between Global Fund-listed and CE marked RDT products compared to those which were not. Similar findings were noted for a panel of 11 HIV RDTs that was assessed with the same checklist as the malaria RDTs.ConclusionRDTs showed shortcomings in desiccant type and information supplied in the IFU.

Integrated rapid-diagnostic-test reader platform on a cellphone.

We demonstrate a cellphone-based rapid-diagnostic-test (RDT) reader platform that can work with various lateral flow immuno-chromatographic assays and similar tests to sense the presence of a target analyte in a sample. This compact and cost-effective digital RDT reader, weighing only ~65 g, mechanically attaches to the existing camera unit of a cellphone, where various types of RDTs can be inserted to be imaged in reflection or transmission modes under light-emitting diode (LED)-based illumination. Captured raw images of these tests are then digitally processed (within less than 0.2 s per image) through a smart application running on the cellphone for validation of the RDT, as well as for automated reading of its diagnostic result. The same smart application then transmits the resulting data, together with the RDT images and other related information (e.g., demographic data), to a central server, which presents the diagnostic results on a world map through geo-tagging. This dynamic spatio-temporal map of various RDT results can then be viewed and shared using internet browsers or through the same cellphone application. We tested this platform using malaria, tuberculosis (TB) and HIV RDTs by installing it on both Android-based smartphones and an iPhone. Providing real-time spatio-temporal statistics for the prevalence of various infectious diseases, this smart RDT reader platform running on cellphones might assist healthcare professionals and policymakers to track emerging epidemics worldwide and help epidemic preparedness.

Field evaluation of five rapid diagnostic tests for screening of HIV-1 infections in rural Rakai, Uganda.

The performance characteristics of HIV rapid diagnostic tests (RDTs) vary by test and by population. We assessed five commercial RDTs in Uganda where all but one RDT (Determine; Abbott Laboratories, Germany) performed close to manufacturer's expectations. Determine had low specificity (85.2%, positive predictive value 67.3%) due to false-positive results with weak-positive bands. Properly trained staff, good quality control programmes and validation of RDTs with laboratories having confirmatory testing capacity may be warranted to assure accuracy in each setting.