False-negative HIV tests using oral fluid tests in children taking antiretroviral therapy from Harare, Zimbabwe

On Campus HIV Self-Testing Distribution at Tertiary Level Colleges in Zimbabwe Increases Access to HIV Testing for Youth

PURPOSE

HIV self-testing allows youth to access testing outside of healthcare facilities. We investigated the feasibility of peer distribution of HIV self-testing (HIVST) kits to youth aged 16-24 years and examined the factors associated with testing off-site rather than at distribution points.

METHODS

From July 2019 to March 2020, HIVST kits were distributed on 12 tertiary education campuses throughout Zimbabwe. Participants chose to test at the HIVST distribution point or off-site. Factors associated with choosing to test off-site and factors associated with reporting a self-test result for those who tested off-site were investigated using logistic regression.

RESULTS

In total, 5,351 participants received an HIVST kit, over 129 days, of whom 3,319 (62%) tested off-site. The median age of recipients was 21 years (interquartile range 20-23); 64% were female. Overall, 2,933 (55%) returned results, 23 (1%) of which were reactive. Being female (adjusted odds ratio [aOR] 1.16, 95% confidence interval [CI] 1.03-1.31), living on campus (aOR 1.24, 95% CI 1.09-1.40), used a condom at last sex (aOR 1.44, 95% CI 1.26-1.65), and previous knowledge of HIVST (aOR 1.22, 95% CI 1.09-1.37) were associated with off-site testing. Attending a vocational college and teachers training college compared to a university was associated with choosing to return results for those who tested off-site (OR 2.40, 95% CI 1.65-3.48, p < .001).

DISCUSSION

HIVST distribution is an effective method of reaching a large number of youth over a short period of time. Efforts to increase awareness and roll out of HIVST on campuses should be coupled with support for linkage to HIV prevention and treatment services.

Influence of Combination Antiretroviral Therapy on HIV-1 Serological Responses and Their Implications: A Systematic Review and Meta-Analysis

We aimed to analyze HIV-1 seroreversion caused by combination antiretroviral therapy (cART) and to explore antibody levels of anti-HIV-1 as an alternative biomarker of HIV-1 reservoir. We searched PubMed, Embase, the Cochrane Library, and Web of Science up to August 2021 for publications about the performance of HIV-1 serological assays or the association between antibody responses against HIV-1 and HIV-1 reservoirs. Potential sources of heterogeneity were explored by meta-regression analysis, including the year of publication, country, pretreatment viral load, sample size, the timing of treatment, time on cART, and principle or type of serological assay. Twenty-eight eligible studies with a total population of 1,883 were included in the meta-analysis. The pooled frequency of HIV-1 seronegativity is 38.0% (95% CI: 28.0%–49.0%) among children with vertical HIV-1 infection and cART initiation at the age of less than 6 months, while the percentage of HIV-1 seronegativity declined to 1.0% (95% CI: 0%–3.0%) when cART was initiated at the age of >6 months. For adult patients, 16.0% (95% CI: 9.0%–24.0%) of them were serologically negative when cART was initiated at acute/early infection of HIV-1, but the seronegative reaction was rarely detected when cART was started at chronic HIV-1 infection. Substantial heterogeneity was observed among the studies to estimate the frequency of HIV-1 seronegativity in the early-cART population (I² ≥ 70%, p < 0.05 and all), while mild heterogeneity existed for the deferred-cART subjects. Moreover, anti-HIV-1 antibody response positively correlates with HIV-1 reservoir size with a pooled rho of 0.43 (95% CI: 0.28–0.55), suggesting that anti-HIV antibody level may be a feasible biomarker of HIV-1 reservoir size.

Brief Report: Diagnostic Accuracy of Oral Mucosal Transudate Tests Compared with Blood-Based Rapid Tests for HIV Among Children Aged 18 Months to 18 Years in Kenya and Zimbabwe

Gaps persist in HIV testing for children who were not tested in prevention of mother-to-child HIV transmission programs. Oral mucosal transudate (OMT) rapid HIV tests have been shown to be highly sensitive in adults, but their performance has not been established in children.

"I wanted evidence that my status had changed, so that is why I tested": experiences with HIV self-testing among female sex workers in Malawi

HIV testing among female sex workers (FSWs) is an established global health priority. HIV self-testing (HIVST) seems to have the potential to address issues of confidentiality, privacy and convenience among this key population. HIVST, however, may result in unintended consequences as its implementation unfolds in a complex sex work context characterised by unequal power relations, stigma and high HIV prevalence. We aimed to explore the experiences of FSWs with HIVST in the context of retesting and antiretroviral usage in Blantyre, Malawi. We used an ethnographic approach to understand meanings and views around HIVST and retesting. We found high levels of retesting, especially among those on antiretroviral, two of which received "false-negative" results. We identified three broad narratives: (1) retesting in response to experiences in the sex work context, (2) retesting driven by the desire to self-monitor HIV-negative status, and (3) retesting in the hope of sero-reversion. The FSWs' experiences indicate that the implementation of HIVST in this context is complex with potential for unintended harms such as coercive testing. HIVST programmes must include clear and appropriate messaging to reduce retesting while on ART and implement strategies to address FSW concerns and anxieties about the accuracy of their HIV-positive test results.

Decreased Seroreactivity in Individuals Initiating Antiretroviral Therapy during Acute HIV Infection

Antiretroviral therapy (ART) during acute HIV infection (AHI) interrupts viral dynamics and may delay the emergence of serological markers targeted by current HIV screening and confirmatory assays, thus creating challenges for correctly classifying HIV infection status. The performance of three HIV antigen/antibody combination (HIV Ag/Ab Combo) assays (the Bio-Rad GS, Abbott Architect, and Bio-Rad BioPlex 2200 assays) was evaluated with samples collected from RV254/South East Asia Research Collaboration in HIV 010 (RV254/SEARCH010) study (Bangkok, Thailand) participants at weeks 12 and 24 following the initiation of ART at Fiebig stage I (FI) (n = 23), FII (n = 39), or FIII/IV (n = 22). Supplemental, confirmatory testing was performed by the Geenius HIV 1/2 and HIV-1 Western blot assays (Bio-Rad). Samples from 30 untreated, HIV-1-infected individuals demonstrated robust HIV Ag/Ab Combo assay reactivity with well-developed HIV-1 Western blotting profiles by 24 weeks after infection. In contrast, 52.2% of samples from individuals initiating ART at FI, 7.7% of samples from individuals initiating ART at FII, and 4.5% of samples from individuals initiating ART at FIII/IV were nonreactive by the HIV Ag/Ab Combo assays, with 36.4 to 39.1% of samples having low signal-to-cutoff (S/CO) results by the Architect and BioPlex assays (S/CO < 10). Seroreversion from a reactive to a nonreactive status was observed in 10 individuals initiating ART at FII and 3 individuals initiating ART at FIII/IV. The Geenius and HIV-1 Western blot assay results were negative or indeterminate for 73.9% and 69.6% of individuals, respectively, treated at FI; 50.0% and 26.3% of individuals, respectively, treated at FII; and 54.5% and 40.9% of individuals, respectively, treated at FIII/IV. Virologic suppression of HIV-1 by ART during AHI impedes seroconversion to biomarkers of infection, limiting the utility of HIV Ag/Ab Combo and supplemental, confirmatory assays for infection status determination.

Cost implications of HIV retesting for verification in Africa

INTRODUCTION

HIV misdiagnosis leads to severe individual and public health consequences. Retesting for verification of all HIV-positive cases prior to antiretroviral therapy initiation can reduce HIV misdiagnosis, yet this practice has not been not widely implemented.

METHODS

We evaluated and compared the cost of retesting for verification of HIV seropositivity (retesting) to the cost of antiretroviral treatment (ART) for misdiagnosed cases in the absence of retesting (no retesting), from the perspective of the health care system. We estimated the number of misdiagnosed cases based on a review of misdiagnosis rates, and the number of positives persons needing ART initiation by 2020. We presented the total and per person costs of retesting as compared to no retesting, over a ten-year horizon, across 50 countries in Africa grouped by income level. We conducted univariate sensitivity analysis on all model input parameters, and threshold analysis to evaluate the parameter values where the total costs of retesting and the costs no retesting are equivalent. Cost data were adjusted to 2017 United States Dollars.

RESULTS AND DISCUSSION

The estimated number of misdiagnoses, in the absence of retesting was 156,117, 52,720 and 29,884 for lower-income countries (LICs), lower-middle income countries (LMICs), and upper middle-income countries (UMICs), respectively, totaling 240,463 for Africa. Under the retesting scenario, costs per person initially diagnosed were: $40, $21, and $42, for LICs, LMICs, and UMICs, respectively. When retesting for verification is implemented, the savings in unnecessary ART were $125, $43, and $75 per person initially diagnosed, for LICs, LMICs, and UMICs, respectively. Over the ten-year horizon, the total costs under the retesting scenario, over all country income levels, was $475 million, and was $1.192 billion under the no retesting scenario, representing total estimated savings of $717 million in HIV treatment costs averted.

CONCLUSIONS

Results show that to reduce HIV misdiagnosis, countries in Africa should implement the WHO's recommendation of retesting for verification prior to ART initiation, as part of a comprehensive quality assurance program for HIV testing services.

Investigating the addition of oral HIV self-tests among populations with high testing coverage - Do they add value? Lessons from a study in Khayelitsha, South Africa

INTRODUCTION

HIV self-testing (HIVST) offers a useful addition to HIV testing services and enables individuals to test privately. Despite recommendations to the contrary, repeat HIV testing is frequent among people already on anti-retroviral treatment (ART) and there are concerns that oral self-testing might lead to false negative results. A study was conducted in Khayelitsha, South Africa, to assess feasibility and uptake of HIVST and linkage-to-care following HIVST.

METHODS

Participants were recruited at two health facilities from 1 March 2016 to 31 March 2017. People under 18 years, or with self-reported previously-diagnosed HIV infection, were excluded. Participants received an OraQuick Rapid HIV-1/2 Antibody kit, and reported their HIVST results by pre-paid text message (SMS) or by returning to the facility. Those not reporting within 7 days were contacted by phone. Electronic and paper-based clinical and laboratory records were retrospectively examined for all participants to identify known HIV outcomes, after matching for name, date of birth, and sex. These findings were compared with self-reported HIVST results where available.

RESULTS

Of 639 participants, 401 (62.8%) self-reported a negative HIVST result, 27 (4.2%) a positive result, and 211 (33.0%) did not report. The record search identified that of the 401 participants self-reporting a negative HIVST result, 19 (4.7%) were already known to be HIV positive; of the 27 self-reporting positive, 12 (44%) were known HIV positive. Overall, records showed 57/639 (8.9%) were HIV positive of whom 39/57 (68.4%) had previously-diagnosed infection and 18/57 (31.6%) newly-diagnosed infection. Of the 428 participants who self-reported a result, 366 (85.5%) reported by SMS.

CONCLUSIONS

HIVST can improve HIV testing uptake and linkage to care. SMS is acceptable for reporting HIVST results but negative self-reports by participants may be unreliable. Use of HIVST by individuals on ART is frequent despite recommendations to the contrary and its implications need further consideration.

To err is human, to correct is public health: a systematic review examining poor quality testing and misdiagnosis of HIV status

INTRODUCTION

In accordance with global testing and treatment targets, many countries are seeking ways to reach the "90-90-90" goals, starting with diagnosing 90% of all people with HIV. Quality HIV testing services are needed to enable people with HIV to be diagnosed and linked to treatment as early as possible. It is essential that opportunities to reach people with undiagnosed HIV are not missed, diagnoses are correct and HIV-negative individuals are not inadvertently initiated on life-long treatment. We conducted this systematic review to assess the magnitude of misdiagnosis and to describe poor HIV testing practices using rapid diagnostic tests.

METHODS

We systematically searched peer-reviewed articles, abstracts and grey literature published from 1 January 1990 to 19 April 2017. Studies were included if they used at least two rapid diagnostic tests and reported on HIV misdiagnosis, factors related to potential misdiagnosis or described quality issues and errors related to HIV testing.

RESULTS

Sixty-four studies were included in this review. A small proportion of false positive (median 3.1%, interquartile range (IQR): 0.4-5.2%) and false negative (median: 0.4%, IQR: 0-3.9%) diagnoses were identified. Suboptimal testing strategies were the most common factor in studies reporting misdiagnoses, particularly false positive diagnoses due to using a "tiebreaker" test to resolve discrepant test results. A substantial proportion of false negative diagnoses were related to retesting among people on antiretroviral therapy. Conclusions HIV testing errors and poor practices, particularly those resulting in false positive or false negative diagnoses, do occur but are preventable. Efforts to accelerate HIV diagnosis and linkage to treatment should be complemented by efforts to improve the quality of HIV testing services and strengthen the quality management systems, particularly the use of validated testing algorithms and strategies, retesting people diagnosed with HIV before initiating treatment and providing clear messages to people with HIV on treatment on the risk of a "false negative" test result.