Field evaluation of HIV point-of-care testing for early infant diagnosis in Cape Town, South Africa

Accurate and reproducible enumeration of CD4 T cell counts and Hemoglobin levels using a point of care system: Comparison with conventional laboratory based testing systems in a clinical reference laboratory in Cameroon

BACKGROUND

Measurements of CD4 T cells and hemoglobin (Hb) are conventionally used to determine the immunological state and disease progression for HIV-infected patients. We obtained a small lightweight point-of-care device, the BD FACSPrestoTM in order to demonstrate its ability to deliver CD4 and Hb analysis in comparison with two larger clinical machines the BDFACSCantoTM analyzer and Sysmex XN 1000 haematology analyzer. The advantages of using the POC device include access to HIV patient data in remote and in resource limited settings.

METHOD

The analytical performance of the BD FACSPrestoTM, compared with the FACSCantoTM II flow cytometer and the Sysmex XN 1000 haematology analyzer was evaluated by testing 241 routine clinical specimens collected in EDTA tubes from patients attending the Immunology and Microbiology laboratory of Chantal BIYA International Reference Centre (Yaounde, Cameroon) between January and May 2016.

RESULTS

The mean in absolute counts and percentage of CD4 T cells was 606 cells/mL and 25% respectively via the FACSPrestoTM, and 574 cells/mL and 24% respectively via the BD FACSCantoTM II. The mean concentration of Hb levels was 11.90 on the Sysmex XN 1000 and 11.45 via the BD FACSPrestoTM, A high correlation (R2 = 0.95, P < 0.001) of Hb level measurements was noted between the BD FACSPrestoTM and Sysmex XN 1000 hematology analyzer. Overall, a Bland-Altman plot of the differences between the two methods showed an excellent agreement for absolute and percentage CD4 counts and hemoglobin measurements between POC and conventional methods evaluated here. Furthermore, the study demonstrated the ease of use of the BD FACSPrestoTM POC technology in remote areas.

CONCLUSION

The BD FACPrestoTM is a suitable tool for CD4 enumeration in resource-limited settings, specifically providing a deployable, reliable POC testing option. The BD FACSPrestoTM performed appropriately in comparison to the conventional reference standard technologies. The BD FACSPrestoTM, system provides accurate, reliable, precise CD4/%CD4/Hb results on venous blood sampling. The data showed good agreement between the BD FACSPrestoTM, BD FACSCantoTM II and Sysmex XN 1000 XN 1000 systems.

The Cascade of Care for Early Infant Diagnosis in Zimbabwe: Point of Care HIV Testing at Birth and 6-8 Weeks

BACKGROUND

Routine birth testing of HIV-exposed infants (HEI) using point of care (POC) nucleic acid testing may allow for earlier diagnosis and treatment of infants living with HIV, but more data are needed on retention in care for those diagnosed at birth and re-testing for those with a negative HIV birth test.

METHODS

POC birth testing (within 48 hours of birth) was offered to all HEI born at 10 public maternities in Zimbabwe from November 2018 to July 2019. Data were abstracted from routine registers, including information on re-testing at 6-8 weeks for infants testing HIV-negative at birth and 6-month retention in care among infants diagnosed with HIV at birth.

RESULTS

Of 2854 eligible HEIs, 2806 (98.3%) received POC HIV birth testing. Thirty-nine infants with HIV were identified (1.4%), and 23 (59%) were started on antiretroviral therapy (ART). Twenty infants (51%) remained on ART at 6 months. Of the 2694 infants who tested negative at birth, 1229 (46.5%) had a documented retest at 6-8 weeks. 7 (0.6%) of those infants tested HIV-positive.

CONCLUSIONS

The uptake of POC birth testing was high in study facilities, but low rates of ART initiation after a positive birth test, despite high retention on ART through 6 months, diminish the impact of POC birth testing and must be addressed. Among infants who tested negative at birth, rates of testing at 6-8 weeks of life (46%) were slightly lower than national rates of testing at the same age without a birth test (56%) during the study period. Improving infant HIV testing rates at 6-8 weeks, regardless of birth testing, should be a priority.

Assessing the acceptability of technological health innovations in sub-Saharan Africa: a scoping review and a best fit framework synthesis

Acceptability is a key concept used to analyze the introduction of a health innovation in a specific setting. However, there seems to be a lack of clarity in this notion, both conceptually and practically. In low and middle-income countries, programs to support the diffusion of new technological tools are multiplying. They face challenges and difficulties that need to be understood with an in-depth analysis of the acceptability of these innovations. We performed a scoping review to explore the theories, methods and conceptual frameworks that have been used to measure and understand the acceptability of technological health innovations in sub-Saharan Africa. The review confirmed the lack of common definitions, conceptualizations and practical tools addressing the acceptability of health innovations. To synthesize and combine evidence, both theoretically and empirically, we then used the "best fit framework synthesis" method. Based on five conceptual and theoretical frameworks from scientific literature and evidence from 33 empirical studies, we built a conceptual framework in order to understand the acceptability of technological health innovations. This framework comprises 6 determinants (compatibility, social influence, personal emotions, perceived disadvantages, perceived advantages and perceived complexity) and two moderating factors (intervention and context). This knowledge synthesis work has also enabled us to propose a chronology of the different stages of acceptability.

“Testing Can Be Done Anywhere”: A Qualitative Assessment of Targeted Community-Based Point-of-Care Early Infant Diagnosis of HIV in Lusaka, Zambia

Community-based point-of-care testing is an acceptable, appropriate, and feasible strategy for improving access to HIV diagnostic services for high-risk HIV-exposed infants.

Introduction:

Delayed HIV diagnosis in HIV-exposed infants (HEIs) results in missed opportunities for early antiretroviral therapy (ART), causing significant morbidity and mortality. Early infant diagnosis (EID) depends on the availability of accessible and reliable testing services. We explored the acceptability, appropriateness, and feasibility of deploying a targeted community-based point-of-care (POC) EID testing model (i.e., “community POC model”) to reach high-risk mother-infant pairs (MIPs) in Lusaka, Zambia.

Methods:

We conducted in-depth interviews with a purposive sample of health care workers, study staff, and caregivers in high-risk MIPs at 6 health facilities included in a larger implementation research study evaluating the community POC model. We defined “high-risk MIPs” as mothers who did not receive antenatal testing or an attended delivery or infants who missed EID testing milestones. Interviews were audio-recorded, translated, and transcribed verbatim in English. Content and thematic analysis were done using NVivo 10 software.

Results:

Health care workers (n=20) and study staff (n=12) who implemented the community POC model noted that the portability and on-screen prompts of the POC platform made it mobile and easy to use, but maintenance and supply chain management were key to field operations. Respondents also felt that the community POC model reached more infants who had never had EID testing, allowing them to find infants with HIV infection and immediately initiate them on ART. Caregivers (n=22) found the community POC model acceptable, provided that privacy could be ensured because the service was convenient and delivered close to home.

Conclusion:

We demonstrate the acceptability, appropriateness, and feasibility of implementing the community POC model in Zambia, while identifying potential challenges related to client privacy and platform field operations. The community POC model may represent a promising strategy to further facilitate active HIV case finding and linkage to ART for children with undiagnosed HIV infection in the community.

A Randomized Trial of Point-of-Care Early Infant HIV Diagnosis in Zambia

BACKGROUND

Point-of-care (POC) early infant diagnosis (EID) provides same-day results and the potential for immediate initiation of antiretroviral therapy (ART).

METHODS

We conducted a pragmatic trial at six public clinics in Zambia. HIV-exposed infants were individually randomized to either: (a) POC EID - on-site testing with the Alere q HIV-1/2 Detect or (b) enhanced standard of care (SOC) EID - off-site testing at a public laboratory. HIV-infected infants were referred for ART and followed for 12 months. Our primary outcome was defined as alive, in care, and virally suppressed at 12 months.

RESULTS

Between March 2016 and November 2018, we randomized 4,000 HIV-exposed infants to POC (n=1,989) or SOC (n=2,011). All but two infants in the POC group received same-day results, while the median time to result in the SOC group was 27 (IQR: 22-30) days. Eighty-one (2%, 95% CI: 1.6-2.5%) infants were diagnosed with HIV. Although ART initiation was high, there were 15 (19%) deaths, 15 (19%) follow-up losses, and 31 (38%) virologic failures. By 12 months, only 20 of 81 (25%, 95% CI: 15-34%) HIV-infected infants were alive, in care, and virally suppressed: 13 (30%, 95% CI: 16-43%) infants in the POC group vs. 7 (19%, 95% CI: 6-32%) in the SOC group (RR: 1.56, 95% CI: 0.7-3.50).

CONCLUSIONS

POC EID eliminated diagnostic delays and accelerated ART initiation but did not translate into definitive improvement in 12-month outcomes. In settings where centralized EID is well functioning, POC EID is unlikely to improve pediatric HIV outcomes.

Operational experiences associated with the implementation of near point-of-care early infant diagnosis of HIV in Myanmar: a qualitative study

Background

Timely diagnosis and early initiation of life-saving antiretroviral therapy are critical factors in preventing mortality among HIV-infected infants. However, resource-limited settings experience numerous challenges associated with centralised laboratory-based testing, including low rates of testing, complex sample referral pathways and unacceptably long turnaround times for results. Point-of-care (POC) HIV testing for HIV-exposed infants can enable same-day communication of results and early treatment initiation for HIV-infected infants. However, complex operational issues and service integration can limit utility and must be well understood prior to implementation.

We explored and documented the challenges and enabling factors in implementing the POC Xpert® HIV-1 Qual test (Cepheid, Sunnyvale, CA, USA) for early infant diagnosis (EID) as part of routine services in four public hospitals in Myanmar.

Methods

This sub-study was part of a randomised controlled stepped-wedge trial (Australian and New Zealand Clinical Trials Registry, number 12616000734460) designed to investigate the impact of POC testing for EID in Myanmar and Papua New Guinea. Infants recruited during the intervention phase underwent POC testing at the participating hospitals as part of routine care. Semi-structured interviews with 23 caregivers, 12 healthcare providers and 10 key informants were used to explore experiences of POC-EID testing. The research team and hospital staff documented and discussed implementation challenges throughout the study.

Results

Overall, caregivers and healthcare workers were satisfied with the short turnaround time of the POC test. Occasional delays in POC testing were mostly attributable to late receipt of samples by laboratory technicians and communication constraints among healthcare staff. Hospital staff valued technical assistance from the research group and the National Health Laboratory. Despite staff shortages and infrastructure challenges such as unreliable electricity supply and cramped space, healthcare workers and caregivers found the implementation of the POC test to be feasible at pilot sites.

Conclusions

As plans for national scale-up evolve, there needs to be a continual focus on staff training, communication pathways and infrastructure. Other models of care, such as allowing non-laboratory-trained personnel to perform POC testing, and cost effectiveness should also be evaluated.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06797-3.

Point-of-care tests detecting HIV nucleic acids for diagnosis of HIV-1 or HIV-2 infection in infants and children aged 18 months or less

BACKGROUND

The standard method of diagnosing HIV in infants and children less than 18 months is with a nucleic acid amplification test reverse transcriptase polymerase chain reaction test (NAT RT-PCR) detecting viral ribonucleic acid (RNA). Laboratory testing using the RT-PCR platform for HIV infection is limited by poor access, logistical support, and delays in relaying test results and initiating therapy in low-resource settings. The use of rapid diagnostic tests at or near the point-of-care (POC) can increase access to early diagnosis of HIV infection in infants and children less than 18 months of age and timely initiation of antiretroviral therapy (ART).

OBJECTIVES

To summarize the diagnostic accuracy of point-of-care nucleic acid-based testing (POC NAT) to detect HIV-1/HIV-2 infection in infants and children aged 18 months or less exposed to HIV infection.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (until 2 February 2021), MEDLINE and Embase (until 1 February 2021), and LILACS and Web of Science (until 2 February 2021) with no language or publication status restriction. We also searched conference websites and clinical trial registries, tracked reference lists of included studies and relevant systematic reviews, and consulted experts for potentially eligible studies.

SELECTION CRITERIA

We defined POC tests as rapid diagnostic tests conducted at or near the patient site. We included any primary study that compared the results of a POC NAT to a reference standard of laboratory NAT RT-PCR or total nucleic acid testing to detect the presence or absence of HIV infection denoted by HIV viral nucleic acids in infants and children aged 18 months or less who were exposed to HIV-1/HIV-2 infection. We included cross-sectional, prospective, and retrospective study designs and those that provided sufficient data to create the 2 × 2 table to calculate sensitivity and specificity. We excluded diagnostic case control studies with healthy controls.

DATA COLLECTION AND ANALYSIS

We extracted information on study characteristics using a pretested standardized data extraction form. We used the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies) tool to assess the risk of bias and applicability concerns of the included studies. Two review authors independently selected and assessed the included studies, resolving any disagreements by consensus. The unit of analysis was the participant. We first conducted preliminary exploratory analyses by plotting estimates of sensitivity and specificity from each study on forest plots and in receiver operating characteristic (ROC) space. For the overall meta-analyses, we pooled estimates of sensitivity and specificity using the bivariate meta-analysis model at a common threshold (presence or absence of infection).

MAIN RESULTS

We identified a total of 12 studies (15 evaluations, 15,120 participants). All studies were conducted in sub-Saharan Africa. The ages of included infants and children in the evaluations were as follows: at birth (n = 6), ≤ 12 months (n = 3), ≤ 18 months (n = 5), and ≤ 24 months (n = 1). Ten evaluations were field evaluations of the POC NAT test at the point of care, and five were laboratory evaluations of the POC NAT tests.The POC NAT tests evaluated included Alere q HIV-1/2 Detect qualitative test (recently renamed m-PIMA q HIV-1/2 Detect qualitative test) (n = 6), Xpert HIV-1 qualitative test (n = 6), and SAMBA HIV-1 qualitative test (n = 3). POC NAT pooled sensitivity and specificity (95% confidence interval (CI)) against laboratory reference standard tests were 98.6% (96.1 to 99.5) (15 evaluations, 1728 participants) and 99.9% (99.7 to 99.9) (15 evaluations, 13,392 participants) in infants and children ≤ 18 months. Risk of bias in the included studies was mostly low or unclear due to poor reporting. Five evaluations had some concerns for applicability for the index test, as they were POC tests evaluated in a laboratory setting, but there was no difference detected between settings in sensitivity (-1.3% (95% CI -4.1 to 1.5)); and specificity results were similar.

AUTHORS' CONCLUSIONS

For the diagnosis of HIV-1/HIV-2 infection, we found the sensitivity and specificity of POC NAT tests to be high in infants and children aged 18 months or less who were exposed to HIV infection.

"We Need it the Same Day": A Qualitative Study of Caregivers and Community Members' Perspectives Toward the Use of Point-of-Care Early Infant Diagnosis

BACKGROUND

Only half of the infants tested for HIV ever receive results, leading to low uptake of treatment and increased mortality and morbidity rates. Point-of-care (POC) nucleic acid diagnostic machines allow for the possibility of same-day results. In Kenya and Zimbabwe, as part of an evaluation comparing standard of care with POC testing for early infant diagnosis, a qualitative substudy was undertaken to understand the acceptability of POC among caregivers of HIV-exposed infants and community members.

SETTING

Kenya and Zimbabwe.

METHODS

In Kenya, 74 interviews were conducted with caregivers, and 6 focus group discussions were conducted with male and female community members and elders. In Zimbabwe, we conducted 85 interviews and 8 focus group discussions. Data were collected in 2 rounds: 1 before the introduction of POC platforms and 1 after the platforms had been in use for at least 3 months. Interviews were conducted in local languages, and content analysis and constant comparison were used to identify key themes.

RESULTS

Reduced time to receive test results lowered caregiver anxiety about the child's HIV status and allowed families to put children on treatment earlier. Printed POC results were seen by some as more trustworthy than conventional handwritten results, believing this reduced the chance of human error; a few distrusted HIV results were generated too quickly. Community awareness of POC was lower among caregivers of HIV-exposed infants.

CONCLUSION

Caregivers are generally very accepting of receiving POC HIV test results; however, additional sensitization among influential community members about the benefits of POC testing is needed.

The cost-effectiveness of scaling-up rapid point-of-care testing for early infant diagnosis of HIV in southern Zambia

Introduction

Early infant diagnosis (EID) and treatment can prevent much of the HIV-related morbidity and mortality experienced by children but is challenging to implement in sub-Saharan Africa. Point-of-care (PoC) testing would decentralize testing and increase access to rapid diagnosis. The objective of this study was to determine the cost-effectiveness of PoC testing in Southern Province, Zambia.

Methods

A decision tree model was developed to compare health outcomes and costs between the standard of care (SoC) and PoC testing using GeneXpert and m-PIMA platforms. The primary health outcome was antiretroviral treatment (ART) initiation within 60 days of sample collection. Additional outcomes included ART initiation by 12 months of age and death prior to ART initiation. Costs included both capital and recurrent costs. Health outcomes and costs were combined to create incremental cost effectiveness ratios (ICERs).

Results

The proportion of children initiating ART within 60 days increased from 27.8% with SoC to 79.8–82.8% with PoC testing depending on the algorithm and platform. The proportion of children initiating ART by 12 months of age increased from 50.9% with SoC to 84.0–86.5% with PoC testing. The proportion of HIV-infected children dying prior to ART initiation decreased from 18.1% with SoC to 3.8–4.6% with PoC testing. Total program costs were similar for the SoC and GeneXpert but higher for m-PIMA. ICERs for PoC testing were favorable, ranging from $23–1,609 for ART initiation within 60 days, $37–2,491 for ART initiation by 12 months of age, and $90–6,188 for deaths prior to ART initiation. Factors impacting the costs of PoC testing, including the lifespan of the testing instruments and integrated utilization of PoC platforms, had the biggest impact on the ICERs. Integrating utilization across programs decreased costs for the EID program, such that PoC testing was cost-saving in some situations.

Conclusion

PoC testing has the potential to improve linkage to care and ART initiation for HIV-infected infants and should be considered for implementation within EID programs to achieve equity in access to HIV services and reduce HIV-related pediatric morbidity and mortality.

Implementation science in maternity care: a scoping review

BACKGROUND

Despite wide recognition that clinical care should be informed by the best available evidence, this does not always occur. Despite a myriad of theories, models and frameworks to promote evidence-based population health, there is still a long way to go, particularly in maternity care. The aim of this study is to appraise the scientific study of methods to promote the systematic uptake of evidence-based interventions in maternity care. This is achieved by clarifying if and how implementation science theories, models, and frameworks are used.

METHODS

To map relevant literature, a scoping review was conducted of articles published between January 2005 and December 2019, guided by Peters and colleagues' (2015) approach. Specifically, the following academic databases were systematically searched to identify publications that presented findings on implementation science or the implementation process (rather than just the intervention effect): Business Source Complete; CINAHL Plus with Full Text; Health Business Elite; Health Source: Nursing/Academic Edition; Medline; PsycARTICLES; PsycINFO; and PubMed. Information about each study was extracted using a purposely designed data extraction form.

RESULTS

Of the 1181 publications identified, 158 were included in this review. Most of these reported on factors that enabled implementation, including knowledge, training, service provider motivation, effective multilevel coordination, leadership and effective communication-yet there was limited expressed use of a theory, model or framework to guide implementation. Of the 158 publications, 144 solely reported on factors that helped and/or hindered implementation, while only 14 reported the use of a theory, model and/or framework. When a theory, model or framework was used, it typically guided data analysis or, to a lesser extent, the development of data collection tools-rather than for instance, the design of the study.

CONCLUSION

Given that models and frameworks can help to describe phenomenon, and theories can help to both describe and explain it, evidence-based maternity care might be promoted via the greater expressed use of these to ultimately inform implementation science. Specifically, advancing evidence-based maternity care, worldwide, will require the academic community to make greater explicit and judicious use of theories, models, and frameworks.

REGISTRATION

Registered with the Joanna Briggs Institute (registration number not provided).

Uganda's "EID Systems Strengthening" model produces significant gains in testing, linkage, and retention of HIV-exposed and infected infants: An impact evaluation

Introduction

A review of Uganda’s HIV Early Infant Diagnosis (EID) program in 2010 revealed poor retention outcomes for HIV-exposed infants (HEI) after testing. The review informed development of the ‘EID Systems Strengthening’ model: a set of integrated initiatives at health facilities to improve testing, retention, and clinical care of HIV-exposed and infected infants. The program model was piloted at several facilities and later scaled countrywide. This mixed-methods study evaluates the program’s impact and assesses its implementation.

Methods

We conducted a retrospective cohort study at 12 health facilities in Uganda, comprising all HEI tested by DNA PCR from June 2011 to May 2014 (n = 707). Cohort data were collected manually at the health facilities and analyzed. To assess impact, retention outcomes were statistically compared to the baseline study’s cohort outcomes. We conducted a cross-sectional qualitative assessment of program implementation through 1) structured clinic observation and 2) key informant interviews with health workers, district officials, NGO technical managers, and EID trainers (n = 51).

Results

The evaluation cohort comprised 707 HEI (67 HIV+). The baseline study cohort contained 1268 HEI (244 HIV+). Among infants testing HIV+, retention in care at an ART clinic increased from 23% (57/244) to 66% (44/67) (p < .0001). Initiation of HIV+ infants on ART increased from 36% (27/75) to 92% (46/50) (p < .0001). HEI receiving 1st PCR results increased from 57% (718/1268) to 73% (518/707) (p < .0001). Among breastfeeding HEI with negative 1st PCR, 55% (192/352) received a confirmatory PCR test, a substantial increase from baseline period. Testing coverage improved significantly: HIV+ pregnant women who brought their infants for testing after birth increased from 18% (67/367) to 52% (175/334) (p < .0001). HEI were tested younger: mean age at DBS test decreased from 6.96 to 4.21 months (p < .0001). Clinical care for HEI was provided more consistently. Implementation fidelity was strong for most program components. The strongest contributory interventions were establishment of ‘EID Care Points’, integration of clinical care, longitudinal patient tracking, and regular health worker mentorship. Gaps included limited follow up of lost infants, inconsistent buy-in/ownership of health facility management, and challenges sustaining health worker motivation.

Discussion

Uganda’s ‘EID Systems Strengthening’ model has produced significant gains in testing and retention of HEI and HIV+ infants, yet the country still faces major challenges. The 3 core concepts of Uganda’s model are applicable to any country: establish a central service point for HEI, equip it to provide high-quality care and tracking, and develop systems to link HEI to the service point. Uganda’s experience has shown the importance of intensively targeting systemic bottlenecks to HEI retention at facility level, a necessary complement to deploying rapidly scalable technologies and other higher-level initiatives.

Feasibility and acceptability of implementing early infant diagnosis of HIV in Papua New Guinea at the point of care: a qualitative exploration of health worker and key informant perspectives

INTRODUCTION

Early infant diagnosis (EID) of HIV and timely initiation of antiretroviral therapy can significantly reduce morbidity and mortality among HIV-positive infants. Access to EID is limited in many low-income and middle-income settings, particularly those in which standard care involves dried blood spots (DBS) sent to centralised laboratories, such as in Papua New Guinea (PNG). We conducted a qualitative exploration of the feasibility and acceptability of implementing a point-of-care (POC) EID test (Xpert HIV-1 Qualitative assay) among health workers and key stakeholders working within the prevention of mother-to-child transmission of HIV (PMTCT) programme in PNG.

METHODS

This qualitative substudy was conducted as part of a pragmatic trial to investigate the effectiveness of the Xpert HIV-1 Qualitative test for EID in PNG and Myanmar. Semistructured interviews were undertaken with 5 health workers and 13 key informants to explore current services, experiences of EID testing, perspectives on the Xpert test and the feasibility of integrating and scaling up POC EID in PNG. Coding was undertaken using inductive and deductive approaches, drawing on existing acceptability and feasibility frameworks.

RESULTS

Health workers and key informants (N=18) felt EID at POC was feasible to implement and beneficial to HIV-exposed infants and their families, staff and the PMTCT programme more broadly. All study participants highlighted starting HIV-positive infants on treatment immediately as the main advantage of POC EID compared with standard care DBS testing. Health workers identified insufficient resources to follow up infants and caregivers and space constraints in hospitals as barriers to implementation. Participants emphasised the importance of adequate human resources, ongoing training and support, appropriate coordination and a sustainable supply of consumables to ensure effective scale-up of the test throughout PNG.

CONCLUSIONS

Implementation of POC EID in a low HIV prevalence setting such as PNG is likely to be both feasible and beneficial with careful planning and adequate resources.

TRIAL REGISTRATION NUMBER

12616000734460.

Programmatic evaluation of feasibility and efficiency of at birth and 6-week, point of care HIV testing in Kenyan infant

Background

Testing infants at birth and with more efficient point of care (POC) HIV diagnostic can streamline EID and expedite infant ART initiation. We evaluated the implementation of at birth and 6-week POC testing to assess the effectiveness and feasibility when implemented by existing hospital staff in Kenya.

Methods

Four government hospitals were randomly assigned to receive a GeneXpert HIV-1 Qual (n = 2) or Alere m-PIMA (n = 2) machine for POC testing. All HIV-exposed infants enrolled were eligible to receive POC testing at birth and 6-weeks of age. The primary outcome was repeat POC testing, defined as testing both at birth and 6-weeks of age. Secondary outcomes included predictors of repeat POC testing, POC efficiency (turnaround times of key services), and operations (failed POC results, missed opportunities).

Results

Of 626 enrolled infants, 309 (49.4%) received repeat POC testing, 115 (18.4%) were lost to follow up after an at-birth test, 120 (19.2%) received POC testing at 6-weeks only, 80 (12.8%) received no POC testing, and 2 (0.3%) received delayed POC testing (>12 weeks of age). Three (0.4%) were identified as HIV-positive. Of the total 853 POC tests run at birth (n = 424) or 6-weeks (n = 429), 806 (94.5%) had a valid result documented and 792 (98.3%) results had documented maternal notification. Mean time from sample collection to notification was 1.08 days, with 751 (94.8%) notifications on the same day as sample collection. Machine error rates at birth and 6-weeks were 8.5% and 2.5%, respectively. A total of 198 infants presented for care (48 at birth; 150 at 6-weeks) without receiving a POC test, representing missed opportunities for testing.

Discussion

At birth POC testing can streamline infant HIV diagnosis, expedite ART initiation and can be implemented by existing hospital staff. However, maternal disengagement and missed opportunities for testing must be addressed to realize the full benefits of at birth POC testing.

Comparison of Alere q whole blood viral load with DBS and plasma viral load in the classification of HIV virological failure

Background

In remote settings, timely plasma separation and transportation to testing laboratories is an impediment to the access of HIV viral load (VL) testing. Potential solutions are whole blood testing through point of care (POC) assays or dried blood spots (DBS).

Methods

We evaluated the performance of a prototype Alere q whole blood VL protocol and compared it against plasma (Abbott RealTime HIV-1) and DBS VL (Abbott RealTime HIV-1 DBS revised prototype protocol and Roche CAP/CTM HIV-1 v2.0 DBS free virus elution protocol). Virological failure (VF) was defined at >1000 copies/ml.

Results

Of 299 samples, Alere q correctly classified VF in 61% versus 87% by Abbott DBS and 76% by Roche FVE. Performance varied across plasma VL categories. Alere q showed 100% sensitivity. Below 1000 copies/ml of plasma, Alere q demonstrated over-quantification, with 19% specificity. Abbott DBS had 91% sensitivity and the best overall correlation with plasma (r² = 0.72). Roche FVE had the best specificity of 99% but reduced sensitivity of 52%, especially between 1000–10,000 copies/ml of plasma. Correlation was best for all assays at >10,000 copies/ml.

Conclusion

Variability was prominent between the assays. Each method requires optimization to facilitate the implementation of a cut-off with optimal sensitivity and specificity for VF. Although Alere q whole blood assay exhibited excellent sensitivity, the poor specificity of only 19% would lead to unnecessary switching of regimens. Thus any VF detected would need to be confirmed by a more specific assay. Both the Abbott DBS and Roche FVE protocols showed good specificity, however sensitivity was reduced when the plasma VL was 1000–10,000 copies/ml. This could result in delays in detecting VF and accumulation of drug resistance. Field evaluation in settings that have adopted these DBS protocols are necessary.

Factors affecting acceptance of at-birth point of care HIV testing among providers and parents in Kenya: A qualitative study

Background

At-birth and point-of-care (POC) HIV testing are emerging strategies to streamline infant HIV diagnosis and expedite ART initiation for HIV-positive infants. The purpose of this qualitative study was to evaluate factors influencing the provision and acceptance of at-birth POC testing among both HIV care providers and parents of HIV-exposed infants in Kenya.

Methods

We conducted semi-structured interviews with 26 HIV care providers and 35 parents of HIV-exposed infants (including 23 mothers, 6 fathers, and 3 mother-father pairs) at four study hospitals prior to POC implementation. An overview of best available evidence related to POC was presented to participants prior to each interview. Interviews probed about standard EID services, perceived benefits and risk of at-birth and POC testing, and suggested logistics of providing at-birth and POC. Interviews were audio recorded, translated (if necessary), and transcribed verbatim. Using the Transdisciplinary Model of Evidence Based Practice to guide analysis, transcripts were coded based on a priori themes related to environmental context, patient characteristics, and resources.

Results

Most providers (24/26) and parents (30/35) held favorable attitudes towards at-birth POC testing. The potential for earlier results to improve infant care and reduce parental anxiety drove preferences for at-birth POC testing. Parents with unfavorable views towards at-birth POC testing preferred standard testing at 6 weeks so that mothers could heal after birth and have time to bond with their newborn before–possibly–learning that their child was HIV-positive. Providers identified lack of resources (shortage of staff, expertise, and space) as a barrier.

Discussion

While overall acceptability of at-birth POC testing among HIV care providers and parents of HIV-exposed infants may facilitate uptake, barriers remain. Applying a task-shifting approach to implementation and ensuring providers receive training on at-birth POC testing may mitigate provider-related challenges. Comprehensive counseling throughout the antenatal and postpartum periods may mitigate patient-related challenges.

Significant Patient Impact Observed Upon Implementation of Point-of-Care Early Infant Diagnosis Technologies in an Observational Study in Malawi

Background

In Malawi in 2014, <20% of human immunodeficiency virus (HIV)–exposed infants received an early infant diagnosis (EID) test in the first 2 months of life and only 30% of HIV-infected children were on antiretroviral therapy (ART). We sought to understand the potential patient impact of improving timely infant diagnosis and treatment initiation through implementation of point-of-care (POC) EID technologies in Malawi.

Methods

In this observational study, POC EID technologies were introduced into routine services at 7 health facilities across Malawi in September 2015. The primary outcome was the proportion of HIV-infected infants initiating ART within 60 days of sample collection in the POC arm compared to the baseline arm with conventional laboratory-based EID testing.

Results

The time from sample collection to result received by the patient decreased significantly from 56 days (interquartile range [IQR], 30–81 days) in the baseline arm to <1 day in the POC arm (P < .001). Of the HIV-infected infants, the time between sample collection and ART initiation was reduced from 38 days (IQR, 30–54 days) in the baseline arm to <1 day (IQR, 0–1 day) in the POC arm (P = .019). Furthermore, the proportion of HIV-infected infants initiated on ART within 60 days of sample collection increased significantly from 41.9% to 91.1% after the introduction of POC (adjusted risk ratio, 2.28; P < .001).

Conclusions

ART initiation rates were significantly improved with the implementation of same-day POC EID testing compared with referred, longer-turnaround laboratory-based testing.

Systematic review of the performance and clinical utility of point of care HIV-1 RNA testing for diagnosis and care

BACKGROUND

Point of-care (POC) HIV-1 RNA tests which are accurate and easy to use with limited infrastructure are needed in resource-limited settings (RLS). We systematically reviewed evidence of POC test performance compared to laboratory-based HIV-1 RNA assays and the potential utility of these tests for diagnosis and care in RLS.

METHODS

Studies published up to July 2018 were identified by a search of PUBMED, EMBASE, Web of Science, CINAHL and Cochrane Central Register of Controlled Trials. Studies evaluating the use of POC HIV-1 RNA testing for early infant diagnosis (EID), acute HIV infection (AHI) diagnosis, or viral load monitoring (VL), compared to centralized testing, were included. Separate search strategies were used for each testing objective.

RESULTS

197 abstracts were screened and 34 full-text articles were assessed, of which 32 met inclusion criteria. Thirty studies evaluated performance and diagnostic accuracy of POC tests compared to standard reference tests. Two of the thirty and two additional studies with no comparative testing reported on clinical utility of POC results. Five different POC tests (Cepheid GeneXpert HIV-1 Quantitative and Qualitative assays, Alere q HIV-1/2 Detect, SAMBA, Liat HIV Quant and Aptima HIV-1 Quant) were used in 21 studies of VL, 11 of EID and 2 of AHI. POC tests were easy to use, had rapid turnaround times, and comparable accuracy and precision to reference technologies. Sensitivity and specificity were high for EID and AHI but lower for VL. For VL, lower sensitivity was reported for whole blood and dried blood spots compared to plasma samples. Reported error rates for Cepheid GeneXpert Qual (2.0%-5.0%), GeneXpert Quant (2.5%-17.0%) and Alere q HIV-1/2 Detect (3.1%-11.0%) were higher than in WHO prequalification reports. Most errors resolved with retesting; however, inadequate sample volumes often precluded repeat testing. Only two studies used POC results for clinical management, one for EID and another for VL. POC EID resulted in shorter time-to-result, rapid ART initiation, and better retention in care compared to centralised testing.

CONCLUSIONS

Performance of POC HIV-1 RNA tests is comparable to reference assays, and have potential to improve patient outcomes. Additional studies on implementation in limited-resources settings are needed.

Point-of-care HIV testing best practice for early infant diagnosis: an implementation study

Background

With Universal Health Coverage and Integrated People-centred Health Care, streamlined health-systems and respectful care are necessary. South Africa has made great strides in prevention of mother-to-child transmission (PMTCT) but with the great burden of HIV, a minimum of birth and 10-week HIV-PCR testing are required for the estimated 360,000 HIV-exposed infants born annually which presents many challenges including delayed results and loss to follow-up. Point-of-care (POC) HIV testing of infants addresses these challenges well and facilitates initiation of HIV-infected infants rapidly after diagnosis for best clinical outcomes.

Methods

Objectives were to determine accuracy, feasibility and acceptability of POC testing compared to standard-of-care (SOC) central-laboratory testing. HIV-exposed infants for birth PCR testing in hospital (n = 323) and follow-up at a primary health care clinic (n = 117) in Durban, South Africa were included. A baseline situational-analysis reviewed registers and phoned mothers of HIV-exposed infants prior to the intervention. An effectiveness-implementation study of the Alere™q HIV-1/2 Detect POC test (heel-prick specimen processed in 50 min) was compared with SOC with questionnaires to mothers and staff. Stata 14 was used for analysis.

Results

At baseline 2% of birth HIV tests were missed; only 40% of mothers could be contacted; 17% did not receive birth test result; 19% did not have a 10-week test; 39% had not received the 10-week results. There were 5(1.5%) HIV-infected and 318(98.5%) HIV-negative infants detected in hospital with all clinic babies negative. All positive infants commenced ART before discharge. Ultimately POC and SOC had perfect concordance but for 10 SOC tests researchers actively tracked-down results or repeated tests. Turn around times for SOC tests were on average 8-days (IQR 6-10  days) and for POC testing was 0-days. The POC error-rate was 9,6% with all giving a result when repeated. The majority of mothers (92%) preferred POC testing with 7% having no preference. No staff preferred SOC testing with 79% preferring POC and 21% having no preference.

Conclusions

Point-of-care HIV testing for EID is accurate, feasible and acceptable, with benefits of early ART for all positive infants at birth facilities. We recommend that it be considered best practice for EID.

Trial registration

ISRCTN38911104 registered 9 January 2018 – retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6990-z) contains supplementary material, which is available to authorized users.

Assessment of eight nucleic acid amplification technologies for potential use to detect infectious agents in low-resource settings

Nucleic acid amplification technologies (NAATs) are high-performance tools for rapidly and accurately detecting infectious agents. They are widely used in high-income countries to diagnose disease and improve patient care. The complexities associated with test methods, reagents, equipment, quality control and assurance require dedicated laboratories with trained staff, which can exclude their use in low-resource and decentralized healthcare settings. For certain diseases, fully integrated NAAT devices and assays are available for use in environmentally-controlled clinics or emergency rooms where relatively untrained staff can perform testing. However, decentralized settings in many low- and middle-income countries with large burdens of infectious disease are challenged by extreme environments, poor infrastructure, few trained staff and limited financial resources. Therefore, there is an urgent need for low-cost, integrated NAAT tools specifically designed for use in low-resource settings (LRS). Two essential components of integrated NAAT tools are: 1) efficient nucleic acid extraction technologies for diverse and complex sample types; and 2) robust and sensitive nucleic acid amplification and detection technologies. In prior work we reported the performance and workflow capacity for the nucleic acid extraction component. In the current study we evaluated performance of eight novel nucleic acid amplification and detection technologies from seven developers using blinded panels of RNA and/or DNA from three pathogens to assess both diagnostic accuracy and suitability as an essential component for low-cost NAAT in LRS. In this exercise, we noted significant differences in performance among these technologies and identified those most promising for potential further development.

Assessment of Blood Donation and Transfusion in Eastern Uganda: A Mixed-Methods Study

BACKGROUND

Blood and blood products are essential in the management of injuries, medical illnesses, and childbirth. Chronic shortages in the blood supply perpetuates the high levels of morbidity and mortality from injury and treatable diseases. Patients in low- and middle-income countries are frequently unable to access blood units necessary for transfusion in a timely manner.

OBJECTIVES

This study aimed to gain insight into the community and hospital factors that contribute to the observed insufficient supply of blood units available for transfusion at a regional referral hospital in rural Eastern Uganda.

METHODS

A mixed-methods approach was utilized; community members were surveyed on knowledge, attitudes, and practices of blood donation and health professionals were queried on hospital factors affecting blood transfusions. Transfusion records were prospectively collected and analyzed, and the pathway of a single blood unit was observed and recorded.

FINDINGS

Among the 82 community members that were surveyed, knowledge was poor (&lt;50% correct) regarding age, weight, and volume of blood to be able to donate, but participants were overall knowledgeable on general characteristics that would exclude individuals from donating blood. Major themes elicited during qualitative interviews included a positive attitude towards and lack of information regarding blood donation. Health professionals expressed frustration in delayed testing of transfusion transmissible infections. The majority of blood transfusions were allocated to female patients (55.8%) and children under five years of age (33.2%).

CONCLUSIONS

Broadened inclusion and education of the general population in blood donation and increased outreach programs may be promising interventions to increase the blood supply at the Soroti Regional Referral Hospital. To reduce the current bottleneck seen in TTI testing, the feasibility and cost-effectiveness of local TTI testing technology should be investigated further.

"Closing the Gap": Provider Recommendations for Implementing Birth Point of Care HIV Testing

Delays in traditional HIV DNA PCR testing for early infant diagnosis (EID) at 6 weeks of age result in late antiretroviral treatment (ART). Birth point of care (POC) testing is an emerging strategy with the potential to streamline EID services. We elicited providers' recommendations for introducing birth POC testing to guide strategies in Kenya and similar settings. We conducted formative interviews with 26 EID providers from four Kenyan hospitals prior to POC implementation. Providers discussed the need for comprehensive training, covering both EID and POC-specific topics for all key personnel. Providers highlighted equipment considerations, such as protocols for maintenance and safe storage. Providers emphasized the need for maternal counseling to ensure patient acceptance and most agreed that specimen collection for birth POC testing should occur in the maternity department and supported a multidisciplinary approach. Though most providers supported ART initiation based on a positive birth POC result, a few expressed concerns with result validity. To maximize implementation success, provider training, equipment security, maternal counseling, and logistics of testing must be planned and communicated to providers.

Infant HIV testing at birth using point-of-care and conventional HIV DNA PCR: an implementation feasibility pilot study in Kenya

Background

Infant HIV diagnosis by HIV DNA polymerase chain reaction (PCR) testing at the standard 6 weeks of age is often late to mitigate the mortality peak that occurs in HIV positive infants’ first 2–3 months of life. Kenya recently revised their early infant diagnosis (EID) guidelines to include HIV DNA PCR testing at birth (pilot only), 6 weeks, 6 months, and 12 months postnatal and a final 18-month antibody test. The World Health Organization (WHO) approved point-of-care (POC) diagnostic platforms for infant HIV testing in resource-limited countries that could simplify logistics and expedite infant diagnosis. Sustainable scale-up and optimal utility in Kenya and other high-prevalence countries depend on robust implementation studies in diverse clinical settings.

Methods

We will pilot the implementation of birth testing by HIV DNA PCR, as well as two POC testing systems (Xpert HIV-1 Qual [Xpert] and Alere q HIV-1/2 Detect [Alere q]), on specimens collected from Kenyan infants at birth (0 to 2 weeks) and 6 weeks (4 to < 24 weeks) postnatal. The formative phase will inform optimal implementation of birth testing and two POC testing technologies. Qualitative interviews with stakeholders (providers, parents of HIV-exposed infants, and community members) will assess attitudes, barriers, and recommendations to optimize implementation at their respective sites. A non-blinded pilot study at four Kenyan hospitals (n = 2 Xpert, n = 2 Alere q platforms) will evaluate infant HIV POC testing compared with standard of care HIV DNA PCR testing in both the birth and 6-week windows. Objectives of the pilot are to assess uptake, efficiency, quality, implementation variables, user experiences of birth testing with both POC testing systems or with HIV DNA PCR, and costs.

Discussion

This study will generate data on the clinical impact and feasibility of adding HIV testing at birth utilizing POC and traditional PCR HIV testing strategies in resource-limited settings. Data from this pilot will inform the optimal implementation of Kenya’s birth testing guidelines and of POC testing systems for the improvement of EID outcomes.

Trial registration

ClinicalTrials.gov, NCT03435887. Registered 26 February 2018.

Electronic supplementary material

The online version of this article (10.1186/s40814-019-0402-0) contains supplementary material, which is available to authorized users.

p24 revisited: a landscape review of antigen detection for early HIV diagnosis

: Despite major advances in HIV testing, early detection of infection at the point of care (PoC) remains a key challenge. Although rapid antibody PoC and laboratory-based nucleic acid amplification tests dominate the diagnostics market, the viral capsid protein p24 is recognized as an alternative early virological biomarker of infection. However, the detection of ultra-low levels of p24 at the PoC has proven challenging. Here we review the landscape of p24 diagnostics to identify knowledge gaps and barriers and help shape future research agendas. Five hundred and seventy-four research articles to May 2018 that propose or evaluate diagnostic assays for p24 were identified and reviewed. We give a brief history of diagnostic development, and the utility of p24 as a biomarker in different populations such as infants, the newly infected, those on preexposure prophylaxis and self-testers. We review the performance of commercial p24 assays and consider elements such as immune complex disruption, resource-poor settings, prevalence, and assay antibodies. Emerging and ultrasensitive assays are reviewed and show a number of promising approaches but further translation has been limited. We summarize studies on the health economic benefits of using antigen testing. Finally, we speculate on the future uses of high-performance p24 assays, particularly, if available in self-test format.

Performance of point-of-care birth HIV testing in primary health care clinics: An observational cohort study

BACKGROUND

Failure to timely diagnose HIV in infants is a major barrier for scaling-up paediatric antiretroviral treatment (ART). WHO recommends birth testing for earlier diagnosis and to improve test coverage, but current diagnosis takes 2-3 weeks to complete, thereby limiting the ability of care givers to provide follow-on care, especially in low-resource settings. We evaluated the benefit of implementing rapid diagnosis of HIV at birth in primary health care maternity wards in Mozambique.

METHODS AND FINDINGS

Infants born to HIV-infected mothers delivering consecutively at eight primary health care clinics were tested within 24 hours of delivery using on-site POC (Alere q HIV1/2 Detect) and standard laboratory (Roche COBAS AmpliPrep/TaqMan HIV-1 qualitative assay v2.0) testing. Infants were also tested at 4-6 weeks of age with both assays. Of 2,350 HIV-exposed infants enrolled in this implementation research study, 33 tested HIV-positive at birth on both assays. Sensitivity and specificity of POC testing compared with laboratory testing at birth were 100% (95% CI 89·4-100·0) and 100% (95% CI 99·8-100·0), respectively. At 4-6 weeks of age, 61 infants were identified as HIV-positive; of these 29 (47·5%) had a positive test at birth. Testing at both birth and 4-6 weeks identified 71 HIV-positive infants compared with 61 infants by testing at 4-6 weeks alone, a 16% increase. Two infants tested positive at birth but tested HIV-negative during follow-up.

CONCLUSIONS

Adding POC birth testing to the 4-6 week screen may increase access to HIV diagnosis and expedite ART initiation in primary health care settings within low resource settings. Guidance on appropriate confirmatory HIV testing algorithms for birth testing is needed.