Discovery of False Elite Controllers: HIV Antibody-Positive RNA-Negative Blood Donors Found To Be on Antiretroviral Therapy

Suppressed HIV antibody responses following exposure to antiretrovirals - evidence from PrEP randomized trials and early antiretroviral treatment initiation studies

BACKGROUND

Exposure to antiretrovirals at or early after HIV acquisition can suppress viral replication and blunt antibody (Ab) responses; a reduced HIV detectability could impact diagnosis and blood donation screening.

METHODS

We used three antigen (Ag)/Ab assays and one nucleic acid test (NAT) to analyze samples collected in pre-exposure prophylaxis (PrEP) trials (iPrEx; Partners PrEP) before infection detection by Ab-only rapid diagnostic tests (RDTs), and in early antiretroviral treatment (ART) initiation studies (RV254; SIPP).

RESULTS

Reactivity using NAT and Ag/Ab assays in samples collected up to 8 weeks prior to the first reactive RDT from 251 PrEP trials participants varied between 49-61% for active PrEP users and between 27-37% for placebo users. Among RV254 participants, reactivity in Ag/Ab assays was <100% at all timepoints, and lower among those initiating ART earlier. Seroreversions occurred for 29% (16/55), and blood donation screening with NAT and Ag/Ab assays could have missed up to 36% (20/55) of RV254 participants. For SIPP participants, who started ART at later timepoints, Ag/Ab assays identified infections with no evidence of reactivity waning.

CONCLUSION

PrEP and early ART initiation can delay or reduce HIV detectability. Considerations for the implementation of NAT and Ag/Ab tests in PrEP/PEP programs relying on Ab-only RDTs should be balanced according to feasibility and public health impact. While blood transfusion services using Ab-only RDTs for HIV screening should adopt higher sensitivity tests, surveillance and further research are needed to determine the need for novel HIV testing algorithms for those already using NAT and Ag/Ab screening assays.

HIV acute infection and long-term undisclosed HIV status among blood donors from the highly endemic Amazonas state, located in the Brazilian Amazon

BACKGROUND

The Amazonas state/AM and Manaus rank among the highest AIDS detection rates in Brazil. High proportion of HIV infected blood donors and transmission clusters of multidrug antiretroviral/ARV resistant viruses were described in HEMOAM blood donors, a main Amazonas public blood bank. Recent and long-term infections among previously genotyped donors are reported.

METHODS/MATERIALS

The recency immunoassay Lag Avidity EIA (Maxim, USA) was employed. Clinical/CD4/viral load medical file data of the main local HIV management center (FMT-HVD) and ARV treatment/ART data were reviewed.

RESULTS

Among 142 HIV-blood donors, chronic infection predominated (n = 87; 61.3 %), 79 based on LAg EIA and 8 undisclosed HIV identified in FMT-HVD records, mostly young adult, single males, 4 repeat donors, all ART-naive. Recent infections represented 30.3 % (n = 43), 39 identified by LAg EIA and 4 immunologic windows (antibody negative/NAT/RNA positive). The overall profile of recent and long-term infections was similar, including moderate rate of transmitted drug resistance/TDR, however with multiple resistance mutations to more than one ARV-class, suggesting ART/failure.

DISCUSSION

Recent/acute and undisclosed/long-term HIV infections represent blood safety alerts suggesting test-seeking behavior of at-risk populations. Early ART use in Brazil, can turn HIV diagnosis more challenging representing a blood transfusion risk in the highly endemic Brazilian Amazon.

The impact of non-disclosure of HIV status and antiretroviral therapy on HIV recency testing and incidence algorithms

BACKGROUND AND OBJECTIVES

Accurate HIV incidence estimates among blood donors are necessary to assess the effectiveness of programs aimed at limiting transfusion-transmitted HIV. We assessed the impact of undisclosed HIV status and antiretroviral (ARV) use on HIV recency and incidence estimates using increasingly comprehensive recent infection testing algorithms.

MATERIALS AND METHODS

Using 2017 donation data from first-time and lapsed donors, we populated four HIV recency algorithms: (1) serology and limiting-antigen avidity testing, (2) with individual donation nucleic amplification testing (ID-NAT) added to Algorithm 1, (3) with viral load added to Algorithm 2 and (4) with ARV testing added to Algorithm 3. Algorithm-specific mean durations of recent infection (MDRI) and false recency rates (FRR) were calculated and used to derive and compare incidence estimates.

RESULTS

Compared with Algorithm 4, progressive algorithms misclassified fewer donors as recent: Algorithm 1: 61 (12.1%); Algorithm 2: 14 (2.8%) and Algorithm 3: 3 (0.6%). Algorithm-specific MDRI and FRR values resulted in marginally lower incidence estimates: Algorithm 1: 0.19% per annum (p.a.) (95% confidence interval [CI]: 0.13%-0.26%); Algorithm 2: 0.18% p.a. (95% CI: 0.13%-0.22%); Algorithm 3: 0.17% p.a. (95% CI: 0.13%-0.22%) and Algorithm 4: 0.17% p.a. (95% CI: 0.13%-0.21%).

CONCLUSION

We confirmed significant misclassification of recent HIV cases when not including viral load and ARV testing. Context-specific MDRI and FRR resulted in progressively lower incidence estimates but did not fully account for the context-specific variability in incidence modelling. The inclusion of ARV testing, in addition to viral load and ID-NAT testing, did not have a significant impact on incidence estimates.

Prevalence, incidence, risk factors and residual risk associated with viral infections among eligible Brazilian blood donors

Knowledge regarding the profile of eligible blood donors presenting positive results in laboratory screening is essential for reducing transfusion-transmitted human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV). Our study aimed to evaluate the prevalence, incidence, predictor variables and residual risk (RR) of HIV/HBV/HCV in blood bags donated in Minas Gerais, Brazil. This study analysed data retrieved from the records of a large blood bank relating to donations collected at multiple centres within the period 2012-2018, during which 1 991 120 blood bags were screened using immunoassays and nucleic acid tests (NATs). Multilevel modelling was used to investigate the association between sex, civil status and age group with HIV/HBV/HCV. RR was estimated from the incidence values (restricted to negative and positive tests within the study period) and window periods for infections. The prevalence in first time donors, incidence and RR of HCV (223.73 cases per 100 000; 54.84 per 100 000 persons-year and 1.6527 per 100 000, respectively) were higher than those of HIV (172.65 cases per 100 000; 28.25 per 100 000 persons-year and 0.8514 per 100 000) and HBV (168.17 cases per 100 000; 18.54 per 100 000 persons-year and 0.5588 per 100 000). The odds of acquiring infection were greater in male, single and older donors. Sixteen donors were identified as seronegative and NATs+ during the 7-year span of the study. Our study has clarified some spatiotemporal trends regarding HIV/HBV/HCV infections in donated blood in Brazil. The results will contribute to the formulation of directives addressed to high-risk donors.

Detection of unreported usage of the antiretroviral drug lamivudine in two blood donors

BACKGROUND

Unreported HIV antiretroviral (ARV) drug usage by blood donors compromises the ability to detect evidence of HIV infection in blood screening tests and represents a risk for blood transfusion safety. Our objective was to determine the frequency of undeclared ARV drug use by blood donors with altered HIV markers.

STUDY DESIGN AND METHODS

This was a retrospective cross-sectional analysis of donations that were tested for HIV antibody (ab), antigen (ag), and RNA by chemiluminescent immunoassay and nucleic acid screening tests. Positive samples were retested and were subjected to ARV drug testing by high-performance liquid chromatography-tandem mass spectrometry.

RESULTS

Of 345,252 blood donations, 361 (0.1%) were positive on initial testing. Samples from 296 (81.9%) of these donations were available for further analysis. The presence of HIV ab/ag and/or RNA was confirmed in 83 (28.0%) of these samples. All 296 bloods were subjected to ARV testing. The ARV drug lamivudine, at 11.3 and 6.7 ng/mL, was detected in 2 of 83 (2.4%) donations that were HIV positive. Other drugs were not detected.

CONCLUSION

Unreported ARV usage was identified in two candidates for blood donation. More intensive efforts to educate donors about disclosure and to investigate the extent of this phenomenon in Brazil are needed.

Leveraging Donor Populations to Study the Epidemiology and Pathogenesis of Transfusion-Transmitted and Emerging Infectious Diseases

The tragedy of transfusion-associated hepatitis and HIV spurred a decades-long overhaul of the regulatory oversight and practice of blood transfusion. Consequent to improved donor selection, testing, process control, clinical transfusion practice and post-transfusion surveillance, transfusion in the United States and other high-income countries is now a very safe medical procedure. Nonetheless, pathogens continue to emerge and threaten the blood supply, highlighting the need for a proactive approach to blood transfusion safety. Blood donor populations and the global transfusion infrastructure are under-utilized resources for the study of infectious diseases. Blood donors are large, demographically diverse subsets of general populations for whom cross-sectional and longitudinal samples are readily accessible for serological and molecular testing. Blood donor collection networks span diverse geographies, including in low- and middle-income countries, where agents, especially zoonotic pathogens, are able to emerge and spread, given limited tools for recognition, surveillance and control. Routine laboratory storage and transportation, coupled with data capture, afford access to rich epidemiological data to assess the epidemiology and pathogenesis of established and emerging infections. Subsequent to the State of the Science in Transfusion Medicine symposium in 2022, our working group (WG), "Emerging Infections: Impact on Blood Science, the Blood Supply, Blood Safety, and Public Health" elected to focus on "leveraging donor populations to study the epidemiology and pathogenesis of transfusion-transmitted and emerging infectious diseases." The 5 landmark studies span (1) the implication of hepatitis C virus in post-transfusion hepatitis, (2) longitudinal evaluation of plasma donors with incident infections, thus informing the development of a widely used staging system for acute HIV infection, (3) explication of the dynamics of early West Nile Virus infection, (4) the deployment of combined molecular and serological donor screening for Babesia microti, to characterize its epidemiology and infectivity and facilitate routine donor screening, and (5) national serosurveillance for SARS-CoV-2 during the COVID-19 pandemic. The studies highlight the interplay between infectious diseases and transfusion medicine, including the imperative to ensure blood transfusion safety and the broader application of blood donor populations to the study of infectious diseases.

Motivations for blood donation by HIV-positive individuals on antiretrovirals in South Africa: A qualitative study

OBJECTIVES

We performed a mixed-methods study to explore the motivations associated with blood donation by donors with known, but undisclosed HIV-positive status and ARV use (HIV+/ARV+), seeking potential strategies to reduce such donations and mitigate risk for blood recipients. Here, we report predominantly the qualitative component.

BACKGROUND

A safe and sustainable blood supply is dependent in part, on effective pre-donation donor assessment. We previously described failure by HIV+/ARV+ blood donors to disclose their status. Such donations may lead to transfusion-transmitted HIV.

METHODS

The social ecological model provided the conceptual framework for this study. Previously identified HIV+/ARV+ donors were invited to complete a survey (including a validated stigma scale) and qualitative interview, which underwent inductive and deductive thematic analysis.

RESULTS

We uncovered two primary motivational paths to HIV+/ARV+ blood donations: privacy and altruism. The latter included a motivation not previously reported in the literature: donating specifically for other people living with HIV (PLWH). The other primary factor was a lack of privacy. These accounts often included donors encountering donation opportunities when accompanied by people to whom they had not and did not plan to disclose their HIV status. Most were highly confident their donations would be identified as HIV-positive and discarded.

CONCLUSION

We demonstrated a complex interaction between individual, social, cultural, and structural/policy factors in blood donations by PLWH who take ARV. Recommendations to limit HIV + ARV+ donations include: (1) Targeted communication strategies to increase knowledge among PLWH of their deferral from blood donation-without increasing stigma, and (2) development of procedures to assist those who feel unable to opt-out of donation due to privacy concerns.

Blood Center Testing Allows the Detection and Rapid Treatment of Acute and Recent HIV Infection

Blood donations in South Africa are tested for HIV RNA using individual donation NAT (ID-NAT), allowing detection and rapid antiretroviral therapy (ART) of acute HIV infections. We enrolled a cohort of acute and recent HIV-infected blood donation candidates in South Africa in 2015-2018, measured HIV antibody, ID-NAT, and recency of infection <195 days (Sedia LAg) at enrollment and initiated early ART. A small cohort of HIV elite controllers was followed without treatment. HIV reservoir measurements included ultrasensitive plasma RNA, cell-associated HIV RNA, and total DNA. Enrollment of 18 Fiebig I-III and 45 Fiebig IV-VI HIV clade C subjects occurred a median of 18 days after index blood donation. ART was administered successfully and compliance with follow-up visits was excellent. There were only minimal differences in HIV reservoir between ART initiation in Fiebig stages I-III vs. IV-VI, but ART noncompliance increased HIV reservoir. In 11 untreated HIV elite controllers, HIV reservoir levels were similar to or higher than those seen in our early treated cohort. National blood services can identify acute HIV cohorts for subsequent HIV cure research studies. Among HIV clade C-infected donors, HIV reservoir differed little by Fiebig stage at treatment initiation, but was smaller than in chronically treated HIV and those with ART noncompliance.

Transfusion-Acquired HIV: History, Evolution of Screening Tests, and Current Challenges of Unreported Antiretroviral Drug Use in Brazil

Prevention of HIV acquisition by blood transfusion from its emergence to the present day is reviewed, and current challenges are delineated. The experience of Fundação Pró-Sangue/Hemocentro de São Paulo, Brazil, is highlighted in the quest for improvements in blood safety and the evolution of increasingly sensitive and specific screening tests. Concerns and establishing stringent criteria in the screening of potential blood donors are emphasized, and the current criteria for identifying and deferring candidates at high risk of acquiring sexually transmitted diseases are summarized. Future challenges relate to the identification of donors with unreported use of antiretroviral drugs for prophylaxis against possible HIV exposure or for treatment of an HIV infection whose viral expression is undetectable by current analyses. There is a need to better understand the motivation of HIV-exposed donors and to educate them about the risk of transfusion-mediated HIV transmission despite having low or undetectable viral loads. In situations in which traditional HIV RNA or antibody detection assays remain negative, more sensitive analyses are needed to identify potential donors at risk for HIV transmission.

The Impact of Early Antiretroviral Treatment (ART) for HIV on the Sensitivity of the Latest Generation of Blood Screening and Point of Care Assays

Introduction: Rapid initiation of antiretroviral therapy (ART) in early HIV infection is important to limit seeding of the viral reservoir. A number of studies have shown that if ART is commenced prior to seroconversion, the seroconversion may, or may not, occur. We aimed to assess whether seroreversion or no seroconversion occurs using samples collected during an early treatment study in South Africa. Methods: We tested 10 longitudinal samples collected over three years from 70 blood donors who initiated ART after detection of acute or early HIV infection during donation screening on fourth- and fifth-generation HIV antibody and RNA assays, and three point of care (POC) rapid tests. Donors were allocated to three treatment groups: (1) very early, (2) early, and (3) later. Longitudinal samples were grouped into time bins post-treatment initiation. Results: On all three high-throughput HIV antibody assays, no clear pattern of declining signal intensity was observed over time after ART initiation in any of the treatment initiation groups and 100% detection was obtained. The Abbott Determine POC assay showed 100% detection at all time points with no seroreversion. However, the Abbott ABON HIV1 and OraSure OraQuick POC assays showed lower proportions of detection in all time bins in the very early treated group, ranging from 50.0% (95% CI: 26.8–73.2%) to 83.1% (95% CI: 64.2–93.0%), and moderate detection rates in the early and later-treated groups. Conclusion: While our findings are generally reassuring for HIV detection when high-throughput serological screening assays are used, POC assays may have lower sensitivity for detection of HIV infection after early treatment. Findings are relevant for blood safety and other settings where POC assays are used.

Mechanism of Viral Suppression among HIV Elite Controllers and Long-Term Nonprogressors in Nigeria and South Africa

A subgroup among people living with HIV (PLHIV) experience viral suppression, sometimes to an undetectable level in the blood and/or are able to maintain a healthy CD4+ T-cell count without the influence of antiretroviral (ARV) therapy. One out of three hundred PLHIV fall into this category, and a large sample of this group can be found in areas with a high prevalence of HIV infection such as Nigeria and South Africa. Understanding the mechanism underpinning the nonprogressive phenotype in this subgroup may provide insights into the control of the global HIV epidemic. This work provides mechanisms of the elite control and nonprogressive phenotype among PLHIV in Nigeria and South Africa and identifies research gaps that will contribute to a better understanding on HIV controllers among PLHIV.

The Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P): A research program striving to improve blood donor safety and optimize transfusion outcomes across the lifespan

BACKGROUND

The Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) is a new iteration of prior National Heart, Lung, and Blood Institute (NHLBI) REDS programs that focus on improving transfusion recipient outcomes across the lifespan as well as the safety and availability of the blood supply.

STUDY DESIGN AND METHODS

The US program includes blood centers and hospitals (22 including 6 free-standing Children's hospitals) in four geographic regions. The Brazilian program has 5 participating hemocenters. A Center for Transfusion Laboratory Studies (CTLS) and a Data Coordinating Center (DCC) support synergistic studies and activities over the 7-year REDS-IV-P program.

RESULTS

The US is building a centralized, vein-to-vein (V2V) database, linking information collected from blood donors, their donations, the resulting manufactured components, and data extracts from hospital electronic medical records of transfused and non-transfused patients. Simultaneously, the Brazilian program is building a donor, donation, and component database. The databases will serve as the backbone for retrospective and prospective observational studies in transfusion epidemiology, transfusion recipient outcomes, blood component quality, and emerging blood safety issues. Special focus will be on preterm infants, patients with sickle cell disease, thalassemia or cancer, and the effect of donor biologic variability and component manufacturing on recipient outcomes. A rapid response capability to emerging safety threats has resulted in timely studies related to Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2).

CONCLUSIONS

The REDS-IV-P program endeavors to improve donor-recipient-linked research with a focus on children and special populations while also maintaining the flexibility to address emerging blood safety issues.

Distinct mechanisms of long-term virologic control in two HIV-infected individuals after treatment interruption of anti-retroviral therapy

Certain infected individuals suppress human immunodeficiency virus (HIV) in the absence of anti-retroviral therapy (ART). Elucidating the underlying mechanism(s) is of high interest. Here we present two contrasting case reports of HIV-infected individuals who controlled plasma viremia for extended periods after undergoing analytical treatment interruption (ATI). In Participant 04, who experienced viral blips and initiated undisclosed self-administration of suboptimal ART detected shortly before day 1,250, phylogenetic analyses of plasma HIV env sequences suggested continuous viral evolution and/or reactivation of pre-existing viral reservoirs over time. Antiviral CD8⁺ T cell activities were higher in Participant 04 than in Participant 30. In contrast, Participant 30 exhibited potent plasma-IgG-mediated neutralization activity against autologous virus that became ineffective when he experienced sudden plasma viral rebound 1,434 d after ATI due to HIV superinfection. Our data provide insight into distinct mechanisms of post-treatment interruption control and highlight the importance of frequent monitoring of undisclosed use of ART and superinfection during the ATI phase.

Influence of unreported HIV prophylaxis on the kinetics of post-blood donation HIV seroconversion

BACKGROUND

In 2020, of 110,000 blood donors screened for HIV exposure two individuals were identified who were viral RNA-positive but seronegative. One of the donors, borderline negative in a pooled screening test for HIV RNA, utilized antiretroviral drugs as post-exposure, pre-donation prophylaxis. The kinetics of subsequent HIV seropositivity in both donors are described.

STUDY DESIGN AND METHODS

Both donors were recalled and interviewed, and blood was obtained at intervals for HIV antibodies and RNA testing.

RESULTS

One donor used antiretroviral prophylaxis for 30 days due to a relationship with an HIV-positive partner. In follow-up samples, seroconversion was noted at 70 days, and viral RNA was detected at 105 days, after blood donation. In contrast, the other donor seroconverted in <25 days and the appearance and titer of HIV RNA was in accordance with the typical pre-seroconversion window.

CONCLUSION

The use of anti-viral prophylaxis by blood donors in the acute phase of HIV infection delays seroconversion. A 6-month deferral in blood donation after HIV prophylaxis, as currently recommended in Brazil, would have been sufficient in this case to mitigate the risk of transfusion-transmitted HIV. Ultimately, improvement in donor compliance with selection procedures for blood donation is needed to optimize blood safety.

Prevalence of undetectable and suppressed viral load in HIV-infected pregnant women initiating Option B+ in Uganda: an observational study nested within a randomized controlled trial

BACKGROUND

Viral load (VL) testing is key in monitoring adherence to antiretroviral therapy (ART) and documenting HIV treatment response. As per HIV treatment guidelines in Uganda, the first VL test is recommended 6 months after initiation of ART. Undetectable VL (uVL) at ART initiation may be helpful in detecting elite controllers in the absence of previous ART use. We investigated viral suppression at ART initiation among a cohort of HIV-positive pregnant women enrolled in the Friends for Life Circles (FLC) for Option B+ randomized controlled trial (RCT).

METHODS

Pregnant women ≥ 18 years of age testing positive for HIV at their first antenatal care visit and starting on ART Option B+ as per the National PMTCT Program guidelines were enrolled into the FLC for Option B+ RCT in urban Kampala and rural Mityana districts of Uganda. Each participant had whole blood samples collected at enrolment to assess baseline VL. Plasma HIV-1 RNA was quantified using COBAS Ampliprep /COBAS Taqman. Baseline VL below 400 RNA copies/ml was considered as viral suppression while baseline VL below 20 RNA copies/ml was considered uVL.

RESULTS

The mean duration from the date of ART initiation to time of sample collection for baseline VL assessment was 4.4 days (SD 3.6). Of the 532 HIV-positive pregnant women enrolled in the FLC for Option B+ study and newly starting Option B+ without a self-reported history of prior ART use, 29 (5.5%) had uVL and 113 (21.4%) had suppressed VL at baseline. There was no association between participants' age, gravidity, marital status, mean monthly income, educational level, disclosure of HIV status to partner, and uVL or viral suppression at baseline. However, non-disclosure of HIV status to any other person was associated with decreased odds of viral suppression at baseline (OR 0.640; 0.416-0.982).

CONCLUSION

Twenty-one percent of HIV-positive Ugandan pregnant women initiating ART (Option B+) showed virological suppression at baseline and were presumed to be "elite controllers" or to have misreported being ART-naive. Further studies are needed to better understand the biologic mechanisms of elite controllers among pregnant women as well as to differentiate elite controllers from concealed ART use. Trial Registration The trial was registered as NCT02515370 (04/08/2015) on Clinicaltrials.gov.

Undisclosed HIV status and antiretroviral therapy use among South African blood donors

BACKGROUND

Undisclosed antiretroviral drug (ARV) use among blood donors who tested HIV antibody positive, but RNA negative, was previously described by our group. Undisclosed ARV use represents a risk to blood transfusion safety. We assessed the prevalence of and associations with undisclosed ARV use among HIV-positive donors who donated during 2017.

STUDY DESIGN AND METHODS

South African National Blood Service (SANBS) blood donors are screened by self-administered questionnaire, semi-structured interview, and individual donation nucleic acid amplification testing for HIV. Stored samples from HIV-positive donations were tested for ARV and characterized as recent/longstanding using lag avidity testing.

RESULTS

Of the 1462 HIV-positive donations in 2017, 1250 had plasma availability for testing of which 122 (9.8%) tested positive for ARV. Undisclosed ARV use did not differ by gender (p = .205) or ethnicity (p = .505) but did differ by age category (p < .0001), donor (p < .0001), clinic type (p = .012), home province (p = .01), and recency (p < .0001). Multivariable logistic regression found older age (adjusted odds ratio [aOR] 3.73, 95% confidence interval [CI] 1.98-7.04 for donors >40 compared with those <21), first-time donation (aOR 5.24; 95% CI 2.48-11.11), and donation in a high HIV-prevalence province (aOR 9.10; 95% CI 2.70-30.72) compared with Northern Rural provinces to be independently associated with undisclosed ARV use.

DISCUSSION

Almost 1 in 10 HIV-positive blood donors neglected to disclose their HIV status and ARV use. Demographic characteristics of donors with undisclosed ARV use differed from those noted in other study. Underlying motivations for nondisclosure among blood donors remain unclear and may differ from those in other populations with significant undisclosed ARV use.

Undisclosed exposure to antiretrovirals prior to treatment initiation: An exploratory analysis

Background

The proportion of individuals with a history of exposure ('pre-exposure') to antiretrovirals (ARVs) prior to formal initiation into antiretroviral treatment (ART) is unknown.

Objectives

This study describes the detection of ARVs in plasma and/or hair, of persons who self-reported no pre-exposure to ART at their first-time initiation onto ART in three clinics in the province of Limpopo, South Africa (SA).

Method

Concentrations of tenofovir (TDF), emtricitabine (FTC) and efavirenz (EFV) in the plasma and hair of individuals initiating ART were analysed using a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Next generation sequences of HIV polymerase gene were analysed with Geneious software 11.15, and drug resistance (DR) mutations were determined according to the Stanford HIV Drug-Resistance database. Participants' demographic data were collected on a structured questionnaire. Data that describe prior exposure to ARV were also collected by this self-reporting method.

Results

Paired blood and hair samples were collected from 77 individuals newly initiated onto ART from 2017 to 2019. We detected at least one of the drugs in the plasma or hair of 41/77 (53.2%) patients who responded with a 'no' to the question 'have you received ARVs before initiation onto ART?' Thirty-one participants (n = 31/77, 40.3%) had TDF in either plasma or hair. Emtricitabine and EFV were found in the plasma or hair of 12/77 (15.6%) and 25/77 (32.4%) of participants respectively. Six (n = 6/77, 7.792%) had all three ARVs in plasma or hair. Prevalence of DR mutations at the > 5% significance threshold level in those known to have had ARV-exposure determined by LC-MS/MS prior to ART-initiation was not significant (χ² = 0.798; p = 0.372), when compared to those who had no prior exposure but still showed DR.

Conclusion

Antiretroviral levels in the hair of individuals initiating treatment imply prolonged prior-exposure to that ARV. The presence of ARV in plasma and hair of persons living with HIV (PLWH) who deny ARV-use, requires an explanation. A larger study at multiple sites and regular DR surveillance of ART-naïve PLWH will be necessary to confirm the generalisability of these findings to the wider South African population.

HIV antiretroviral therapy and prevention use in US blood donors: a new blood safety concern

Antiretroviral therapy (ART) to treat and pre-exposure prophylaxis (PrEP) to prevent HIV infection are effective tools to help end the HIV epidemic. However, their use could affect HIV transfusion-transmission risk. Three different ART/PrEP prevalence analyses in blood donors were conducted. First, blood samples from HIV-positive and a comparison group of infection-nonreactive donors were tested under blind using liquid chromatography-tandem mass spectrometry for ART. Second, blood donor samples from infection-nonreactive, 18- to 45-year-old, male, first-time blood donors in 6 US locations were tested for emtricitabine and tenofovir. Third, in men who have sex with men (MSM) participating in the 2017 Centers for Disease Control and Prevention National HIV Behavioral Surveillance (NHBS) from 5 US cities, self-reported PrEP use proximate to donation was assessed. In blind testing, no ART was detected in 300 infection-nonreactive donor samples, but in 299 HIV confirmed-infected donor samples, 46 (15.4%; 95% confidence interval [CI], 11.5% to 20.0%) had evidence of ART. Of the 1494 samples tested from first-time male donors, 9 (0.6%; 95% CI, 0.03% to 1.1%) had tenofovir and emtricitabine. In the NHBS MSM survey, 27 of 591 respondents (4.8%; 95% CI, 3.2% to 6.9%) reported donating blood in 2016 or 2017 and PrEP use within the same time frame as blood donation. Persons who are HIV positive and taking ART and persons taking PrEP to prevent HIV infection are donating blood. Both situations could lead to increased risk of HIV transfusion transmission if blood screening assays are unable to detect HIV in donations from infected donors.

Pharmacology of HIV Cure: Site of Action

Despite significant advances in HIV treatment over the past 30 years, critical barriers to an HIV cure persist. The HIV reservoir, defined at both the cellular and anatomical level, constitutes the main barrier to cure. While the mechanisms underlying the reservoir are not yet well understood, one theory to explain persistence at the anatomical level is that subtherapeutic exposure to antiretroviral therapy (ART) within certain tissue compartments permits ongoing replication. Characterizing ART pharmacology throughout the body is important in the context of these potential pharmacologic sanctuaries and for maximizing the probability of success with forthcoming cure strategies that rely on latency reversal and require ART to prevent reseeding the reservoir. In this review, we provide a comprehensive overview of ART and latency reversal agent distribution at the site of action for HIV cure (i.e., anatomical sites commonly associated with HIV persistence, such as lymphoid organs and the central nervous system). We also discuss methodologic approaches that provide insight into HIV cure pharmacology, including experimental design and advances within the computational, pharmaceutical, and analytical chemistry fields. The information discussed in this review will assist in streamlining the development of investigational cure strategies by providing a roadmap to ensure therapeutic exposure within the site of action for HIV cure.

A high prevalence of potential HIV elite controllers identified over 30 years in Democratic Republic of Congo

Background

In-depth analysis of the HIV pandemic at its epicenter in the Congo basin has been hampered by 40 years of political unrest and lack of functional public health infrastructure. In recent surveillance studies (2017-18), we found that the prevalence of HIV in Kinshasa, Democratic Republic of Congo (11%) far exceeded previous estimates.

Methods

10,457 participants were screened in Kinshasa with rapid tests from 2017-2019. Individuals confirmed as reactive by the Abbott ARCHITECT HIV Ag/Ab Combo assay (n=1968) were measured by the Abbott RealTime HIV-1 viral load assay. Follow up characterization of samples was performed with alternate manufacturer viral load assays, qPCR for additional blood borne viruses, unbiased next generation sequencing, and HIV Western blotting.

Findings

Our data suggested the existence of a significant cohort (n=429) of HIV antibody positive/viral load negative individuals. We systematically eliminated collection site bias, sample integrity, and viral genetic diversity as alternative explanations for undetectable viral loads. Mass spectroscopy unexpectedly detected the presence of 3TC antiviral medication in approximately 60% of those tested (209/354), and negative Western blot results indicated false positive serology in 12% (49/404). From the remaining Western blot positives (n=53) and indeterminates (n=31) with reactive Combo and rapid test results, we estimate 2.7-4.3% of infections in DRC to be potential elite controllers. We also analyzed samples from the DRC collected in 1987 and 2001-03, when antiretroviral drugs were not available, and found similarly elevated trends.

Interpretation

Viral suppression to undetectable viral loads without therapy occurs infrequently in HIV-1 infected patients around the world. Mining of global data suggests a unique ability to control HIV infection arose early in central Africa and occurs in <1% of founder populations. Identification of this group of elite controllers presents a unique opportunity to study potentially novel genetic mechanisms of viral suppression.

Funding

Abbott Laboratories funded surveillance in DRC and subsequent research efforts. Additional funding was received from a MIZZOU Award from the University of Missouri. Research was supported in part by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH.

HIV incidence in South African blood donors from 2012 to 2016: a comparison of estimation methods

BACKGROUND

Measuring incidence is important for monitoring and maintaining the safety of the blood supply. Blood collected from repeat-donors has provided the opportunity to follow blood donors over time and has been used to estimate the incidence of viral infections. These incidence estimates have been extrapolated to first-time donors using the ratio of NAT yield cases in first-time versus repeat-donors. We describe a model to estimate incidence in first-time donors using the limiting antigen (LAg) avidity assay and compare its results with those from established models.

METHODS

HIV-positive first-time donations were tested for recency using the LAg assay. Three models were compared; incidence estimated for (1) first-time donors using LAg avidity, (2) first-time and repeat-donors separately using the NAT yield window period (WP) model and (3) repeat-donors using the incidence/WP model.

RESULTS

HIV incidence in first-time donors was estimated at 3·32 (CI 3·11, 3·55) and 3·81 (CI 3·07, 4·73) per 1000 PY using the LAg assay and NAT yield WP models, respectively. Incidence in repeat-donors was between 2·0- and 2·5-fold lower than in first-time donors estimated at 1·56 (CI 1·37, 1·77) and 1·94 (CI 1·86-2·01) per 1000 PY using the NAT yield/WP and incidence/WP models, respectively.

CONCLUSION

Testing HIV-positive donations using the LAg assay provides a reliable method to estimate incidence in first-time donors for countries that collect the majority of blood from first-time donors and do not screen with NAT.

Inactivation of a broad spectrum of viruses and parasites by photochemical treatment of plasma and platelets using amotosalen and ultraviolet A light

BACKGROUND

The INTERCEPT Blood System pathogen reduction technology (PRT), which uses amotosalen and ultraviolet A light treatment (amotosalen/UV-PRT), inactivates pathogens in plasma and platelet components (PCs). This review summarizes data describing the inactivation efficacy of amotosalen/UVA-PRT for a broad spectrum of viruses and parasites.

METHODS

Twenty-five enveloped viruses, six nonenveloped viruses (NEVs), and four parasites species were evaluated for sensitivity to amotosalen/UVA-PRT. Pathogens were spiked into plasma and PC at high titers. Samples were collected before and after PRT and assessed for infectivity with cell cultures or animal models. Log reduction factors (LRFs) were defined as the difference in infectious titers before and after amotosalen/UV-PRT.

RESULTS

LRFs of ≥4.0 log were reported for 19 pathogens in plasma (range, ≥4.0 to ≥7.6), 28 pathogens in PC in platelet additive solution (PC-PAS; ≥4.1-≥7.8), and 14 pathogens in PC in 100% plasma (PC-100%; (≥4.3->8.4). Twenty-five enveloped viruses and two NEVs were sensitive to amotosalen/UV-PRT; LRF ranged from >2.9 to ≥7.6 in plasma, 2.4 or greater to greater than 6.9 in PC-PAS and >3.5 to >6.5 in PC-100%. Infectious titers for four parasites were reduced by >4.0 log in all PC and plasma (≥4.9 to >8.4).

CONCLUSION

Amotosalen/UVA-PRT demonstrated effective infectious titer reduction for a broad spectrum of viruses and parasites. This confirms the capacity of this system to reduce the risk of viral and parasitic transfusion-transmitted infections by plasma and PCs in various geographies.

Does antiretroviral therapy use affect the accuracy of HIV rapid diagnostic assays? Experience from a demographic health and surveillance site in rural South Africa

Rapid diagnostic tests (RDTs) are the mainstay of HIV diagnosis in the developing world but might have poor sensitivity among individuals taking antiretroviral therapy (ART). We leveraged a home-based HIV testing program linked to clinical data to compare the sensitivity of RDTs between individuals using versus not using ART. Field workers tested 6802 individuals using 2 HIV RDTs, which were compared to a single HIV immunoassay tested on dried blood spots. Approximately 5% (371/6802) tested positive by immunoassay, of whom 157 (42%) were currently on ART. The sensitivity of the Abon RDT among those never versus currently on ART was 91.6% (95% CI 88.3–94.3) and 96.6% (95% CI 88.3–94.3), respectively, and 95.4% (95% CI 92.8–97.3) versus 99.3% (95% CI 95.2–99.7) for the Advanced Quality assay. We report similar sensitivity of RDTs in ART-naïve and ART-experienced individuals, which mitigates concerns about their use among treated individuals in population-based epidemiologic surveys and those transferring care.