Recent Infection Testing Algorithm Research Articles

An enhanced cross-sectional HIV incidence estimator that incorporates prior HIV test results.

Incidence estimation of HIV infection can be performed using recent infection testing algorithm (RITA) results from a cross-sectional sample. This allows practitioners to understand population trends in the HIV epidemic without having to perform longitudinal follow-up on a cohort of individuals. The utility of the approach is limited by its precision, driven by the (low) sensitivity of the RITA at identifying recent infection. By utilizing results of previous HIV tests that individuals may have taken, we consider an enhanced RITA with increased sensitivity (and specificity). We use it to propose an enhanced estimator for incidence estimation. We prove the theoretical properties of the enhanced estimator and illustrate its numerical performance in simulation studies. We apply the estimator to data from a cluster-randomized trial to study the effect of community-level HIV interventions on HIV incidence. We demonstrate that the enhanced estimator provides a more precise estimate of HIV incidence compared to the standard estimator.

Progress towards the UNAIDS 95-95-95 targets in the Fifth Botswana AIDS Impact Survey (BAIS V 2021): a nationally representative survey

In 2014, UNAIDS set a goal to end the AIDS epidemic by achieving targets for the percentage of people living with HIV who were aware of their status, on antiretroviral therapy (ART), and virally suppressed. In 2020, these targets were revised to 95% for each measure (known as 95-95-95), to be reached among people living with HIV by 2025. We used data from the Fifth Botswana AIDS Impact Survey (BAIS V) to measure progress towards these testing and treatment targets in Botswana. BAIS V used a two-stage cluster design to obtain a nationally representative sample of people aged 15-64 years in Botswana. During March-August, 2021, 14 763 consenting participants were interviewed and tested for HIV in their households by survey teams. HIV-positive specimens were tested for viral load, presence of antiretroviral drugs, and recency of infection using the HIV-1 limiting antigen avidity enzyme immunoassay. Estimates of HIV-positive status and use of ART were based on self-report and the analysis of blood specimens for antiretroviral drugs. Viral load suppression was defined as an HIV RNA concentration of less than 1000 copies per mL. HIV incidence was calculated using the recent infection testing algorithm. Data were weighted to account for the complex survey design. The national HIV prevalence in Botswana among people aged 15-64 years was 20·8% and the annual incidence of HIV infection was 0·2%. 95·1% (men 93·0%, women 96·4%) of people living with HIV aged 15-64 years were aware of their status, 98·0% (men 97·2%, women 98·4%) of those aware were on ART, and 97·9% (men 96·6%, women 98·6%) of those on ART had viral load suppression. Among young people (aged 15-24 years) living with HIV, 84·5% were aware of their status, 98·5% of those aware were on ART, and 91·6% of those on ART had viral load suppression. The prevalance of viral load suppression among all people living with HIV was 91·8%, and varied by district-ranging from 85·3% in Gaborone to 100·0% in Selibe Phikwe. BAIS V is the first population-based survey worldwide to report the achievement of the UNAIDS 95-95-95 goals, both overall and among women. Strategies to reach undiagnosed men and young people, including young women, are needed. US President's Emergency Plan for AIDS Relief.

Risk Factors for Recent HIV Infections among Adults in 14 Countries in Africa Identified by Population-Based HIV Impact Assessment Surveys, 2015-2019.

Identifying persons who have newly acquired HIV infections is critical for characterizing the HIV epidemic direction. We analyzed pooled data from nationally representative Population-Based HIV Impact Assessment surveys conducted across 14 countries in Africa for recent infection risk factors. We included adults 15-49 years of age who had sex during the previous year and used a recent infection testing algorithm to distinguish recent from long-term infections. We collected risk factor information via participant interviews and assessed correlates of recent infection using multinomial logistic regression, incorporating each survey's complex sampling design. Compared with HIV-negative persons, persons with higher odds of recent HIV infection were women, were divorced/separated/widowed, had multiple recent sex partners, had a recent HIV-positive sex partner or one with unknown status, and lived in communities with higher HIV viremia prevalence. Prevention programs focusing on persons at higher risk for HIV and their sexual partners will contribute to reducing HIV incidence.

High Genetic Diversity of HIV-1 and Active Transmission Clusters among Male-to-Male Sexual Contacts (MMSCs) in Zhuhai, China.

Monitoring genetic diversity and recent HIV infections (RHIs) is critical for understanding HIV epidemiology. Here, we report HIV-1 genetic diversity and RHIs in blood samples from 190 HIV-positive MMSCs in Zhuhai, China. MMSCs with newly reported HIV were enrolled from January 2020 to June 2022. A nested PCR was performed to amplify the HIV polymerase gene fragments at HXB2 positions 2604-3606. We constructed genetic transmission network at both 0.5% and 1.5% distance thresholds using the Tamura-Nei93 model. RHIs were identified using a recent infection testing algorithm (RITA) combining limiting antigen avidity enzyme immunoassay (LAg-EIA) assay with clinical data. The results revealed that 19.5% (37/190) were RHIs and 48.4% (92/190) were CRF07_BC. Two clusters were identified at a 0.5% distance threshold. Among them, one was infected with CRF07_BC for the long term, and the other was infected with CRF55_01B recently. We identified a total of 15 clusters at a 1.5% distance threshold. Among them, nine were infected with CRF07_BC subtype, and RHIs were found in 38.8% (19/49) distributed in eight genetic clusters. We identified a large active transmission cluster (n = 10) infected with a genetic variant, CRF79_0107. The multivariable logistic regression model showed that clusters were more likely to be RHIs (adjusted OR: 3.64, 95% CI: 1.51~9.01). The RHI algorithm can help to identify recent or ongoing transmission clusters where the prevention tools are mostly needed. Prompt public health measures are needed to contain the further spread of active transmission clusters.

Estimating potential silent transfer using baseline viral load measures among people presenting as new to HIV care in Lusaka, Zambia: a cross-sectional study

ObjectivesTo estimate potential silent transfer using baseline viral load measures among individuals presenting as new to HIV care in routine HIV clinical settings in Lusaka, Zambia.DesignCross-sectional study.SettingTwo large, urban government-operated...

Improving Biomarker-based HIV Incidence Estimation in the Treatment Era.

Estimating HIV-1 incidence using biomarker assays in cross-sectional surveys is important for understanding the HIV pandemic. However, the utility of these estimates has been limited by uncertainty about what input parameters to use for false recency rate (FRR) and mean duration of recent infection (MDRI) after applying a recent infection testing algorithm (RITA). This article shows how testing and diagnosis reduce both FRR and mean duration of recent infection compared to a treatment-naive population. A new method is proposed for calculating appropriate context-specific estimates of FRR and mean duration of recent infection. The result of this is a new formula for incidence that depends only on reference FRR and mean duration of recent infection parameters derived in an undiagnosed, treatment-naive, nonelite controller, non-AIDS-progressed population. Applying the methodology to eleven cross-sectional surveys in Africa results in good agreement with previous incidence estimates, except in 2 countries with very high reported testing rates. Incidence estimation equations can be adapted to account for the dynamics of treatment and recent infection testing algorithms. This provides a rigorous mathematical foundation for the application of HIV recency assays in cross-sectional surveys.

HIV Incidence, Recent HIV Infection, and Associated Factors, Kenya, 2007-2018.

Nationally representative surveys provide an opportunity to assess trends in recent human immunodeficiency virus (HIV) infection based on assays for recent HIV infection. We assessed HIV incidence in Kenya in 2018 and trends in recent HIV infection among adolescents and adults in Kenya using nationally representative household surveys conducted in 2007, 2012, and 2018. To assess trends, we defined a recent HIV infection testing algorithm (RITA) that classified as recently infected (<12 months) those HIV-positive participants that were recent on the HIV-1 limiting antigen (LAg)-avidity assay without evidence of antiretroviral use. We assessed factors associated with recent and long-term (≥12 months) HIV infection versus no infection using a multinomial logit model while accounting for complex survey design. Of 1,523 HIV-positive participants in 2018, 11 were classified as recent. Annual HIV incidence was 0.14% in 2018 [95% confidence interval (CI) 0.057-0.23], representing 35,900 (95% CI 16,300-55,600) new infections per year in Kenya among persons aged 15-64 years. The percentage of HIV infections that were determined to be recent was similar in 2007 and 2012 but fell significantly from 2012 to 2018 [adjusted odds ratio (aOR) = 0.31, p < .001]. Compared to no HIV infection, being aged 25-34 versus 35-64 years (aOR = 4.2, 95% CI 1.4-13), having more lifetime sex partners (aOR = 5.2, 95% CI 1.6-17 for 2-3 partners and aOR = 8.6, 95% CI 2.8-26 for ≥4 partners vs. 0-1 partners), and never having tested for HIV (aOR = 4.1, 95% CI 1.5-11) were independently associated with recent HIV infection. Although HIV remains a public health priority in Kenya, HIV incidence estimates and trends in recent HIV infection support a significant decrease in new HIV infections from 2012 to 2018, a period of rapid expansion in HIV diagnosis, prevention, and treatment.

Evaluation of antiretroviral therapy effect and prognosis between HIV-1 recent and long-term infection based on a rapid recent infection testing algorithm.

Early diagnosis of HIV-1 infection and immediate initiation of combination antiretroviral therapy (cART) are important for achieving better virological suppression and quicker immune reconstitution. However, no serological HIV-1 recency testing assay has been approved for clinical use, and the real-world clinical outcomes remain to be explored for the subjects with HIV-1 recent infection (RI) or long-term infection (LI) when antiretroviral therapy is initiated. In this study, a HIV-1 rapid recent-infection testing strip (RRITS) was developed and incorporated into the recent infection testing algorithms (RITAs) to distinguish HIV-1 RI and LI and to assess their clinical outcomes including virological response, the recovery of CD4+ T-cell count and CD4/CD8 ratio and the probability of survival. We found that the concordance between our RRITS and the commercially available LAg-Avidity EIA was 97.13% and 90.63% when detecting the longitudinal and cross-sectional HIV-1 positive samples, respectively. Among the 200 HIV-1 patients analyzed, 22.5% (45/200) of them were RI patients and 77.5% (155/200) were chronically infected and 30% (60/200) of them were AIDS patients. After cART, 4.1% (5/155) of the LI patients showed virological rebound, but none in the RI group. The proportion of CD4+ T-cell count >500 cells/mm3 was significantly higher in RI patients than in LI after 2 years of cART with a hazard ratio (HR) of 2.6 (95% CI: 1.9, 3.6, p < 0.0001) while the probability of CD4/CD8 = 1 was higher in RI than in LI group with a HR of 3.6 (95% CI: 2.2, 5.7, p < 0.0001). Furthermore, the immunological recovery speed was 16 cells/mm3/month for CD4+ T-cell and 0.043/month for the ratio of CD4/CD8 in the RI group, and was bigger in the RI group than in the LI patients (p < 0.05) during the 1st year of cART. The survival probability for LI patients was significantly lower than that for RI patients (p < 0.001). Our results indicated that RRITS combined with RITAs could successfully distinguish HIV-1 RI and LI patients whose clinical outcomes were significantly different after cART. The rapid HIV-1 recency test provides a feasible assay for diagnosing HIV-1 recent infection and a useful tool for predicting the outcomes of HIV-1 patients.

Incidence of HIV infection and associated factors among female sex workers in Côte d'Ivoire, results of the ANRS 12361 PrEP-CI study using recent infection assays.

This study aimed to estimate, using an HIV Recent Infection Testing Algorithm (RITA), the HIV incidence and its associated factors among female sex workers (FSW) in Côte d'Ivoire. A cross-sectional study was conducted in 2016-2017 in Abidjan and San Pedro's region among FSW aged ≥ 18 years. In addition, a sociodemographic questionnaire, HIV screening was carried out by two rapid tests. In the event of a positive result, a dried blood spot sample was taken to determine, using a RITA adapted to the Ivorian context, if it was a recent HIV infection. A total of 1000 FSW were surveyed with a median age of 25 years (interquartile range: 21-29 years). 39 (3.9%) tested positive for HIV. The incidence of HIV was estimated to be 2.3 per 100 person-years, with higher incidence rates among those 24 years old or less (3.0% vs. 1.9%), non-Ivorian FSW (3.2% vs. 1.9%) and those with the lowest education level (4.6% in FSW who never went to school vs. 2.6%). The incidence seemed to be associated with the sex work practice conditions: higher incidence among FSW whose usual price was less than 3.50$ (4.3% vs.1.0%), FSW who had a larger number of clients on the last day of work (6.1% in those with 7 clients or more vs. 1.8%), FSW who reported not always using condoms with their clients (8.5% vs. 1.5%) and FSW who reported agreeing to sex without a condom in exchange for a large sum of money (10.1% vs. 1.2%). This study confirms that FSW remain highly exposed to HIV infection. Exposure to HIV is also clearly associated with certain sex-work factors and the material conditions of sex work. Efforts in the fight against HIV infection must be intensified to reduce new infections among FSW.

Characterising persons diagnosed with HIV as either recent or long-term using a cross-sectional analysis of recent infection surveillance data collected in Malawi from September 2019 to March 2020

ObjectivesIn Malawi, a recent infection testing algorithm (RITA) is used to characterise infections of persons newly diagnosed with HIV as recent or long term. This paper shares results from recent...

Recent HIV Infection Among Men Who Have Sex with Men, Transgender Women, and Genderqueer Individuals with Newly Diagnosed HIV Infection in Zimbabwe: Results from a Respondent-Driven Sampling Survey.

In Africa, rapid testing for recent HIV infection (RTRI) is being scaled up; however, use of the recent infection testing algorithm (RITA), which uses viral load (VL) to confirm RTRI-recent infections, is not a widespread practice. We present results of recently acquired HIV infections among men who have sex with men (MSM), transgender women, and genderqueer (TGW/GQ) individuals with newly diagnosed HIV infection in Zimbabwe as per the national approach (RTRI) and applying a RITA. In 2019, 1,538 MSM and TGW/GQ in Harare and Bulawayo, Zimbabwe were recruited to participate in a biobehavioral survey using respondent-driven sampling. Consenting participants received HIV testing and all HIV-positive specimens were tested with the RTRI Asanté HIV-1 Rapid Recency Assay, and for VL and CD4 count. RTRI-recent participants with unsuppressed VL (≥1,000 copies/mL) were classified as RITA-recent. Descriptive statistics were used to summarize results among RTRI-recent and RITA-recent participants. Among those tested for HIV (1,511/1,538), 22.5% (340/1,511) tested positive and of those, 55.0% (187/340) self-reported an HIV-negative or unknown status. Among these, 8.6% (16/187) were classified as RTRI-recent and 91.4% (171/187) were classified as RTRI-long term. After accounting for VL, RITA-recency was 1.1% (2/187). Two of 16 (12.5%) RTRI-recent infections were RITA-recent. VL among RITA-recent cases were 9,052 copies/mL and 40,694 copies/mL and both had CD4 counts <500. Data highlight misclassification of recent infections among MSM and TGW/GQ with newly diagnosed HIV infection using RTRI. With the incorporation of VL, >85% of RTRI-recent cases were reclassified as RITA-long term. True characterization of recent infections may not be possible without VL testing, which remains challenging in resource-limited settings.

Assessment of the Proportion of Recent HIV-1 Infections in Newly-Diagnosed Cases in Ghana.

Accurate monitoring of epidemics is a key strategy for controlling human immunodeficiency virus type-1 (HIV-1) infection. To delineate the characteristics of newly diagnosed cases of HIV-1 infection, we assessed the proportion of recent HIV-1 infections using a recent infection-testing algorithm (RITA). In 2015, 248 cases were newly diagnosed with HIV infection at the Regional Hospital Koforidua, Ghana. Of these, 234 cases (94.4%) were infected with HIV-1 only, four (1.6%) were infected with HIV-2 only, and 10 (4.0%) were co-infected with HIV-1 and HIV-2. All HIV-1 single-seropositive samples were used in the HIV-1 LAg avidity assay for RITA. Our analysis revealed that 18 cases (7.7%) were recently infected, indicating that early diagnosis was not achieved in Ghana. This is the first report to assess the proportion of recent infections in Ghana using a biomarker approach. The accumulation of these data will contribute to the accurate estimation of HIV-1 incidence and prevalence in Ghana.

Performance of a novel rapid test for recent HIV infection among newly-diagnosed pregnant adolescent girls and young women in four high-HIV-prevalence districts-Malawi, 2017-2018.

Tests for recent HIV infection (TRI) distinguish recent from long-term HIV infections using markers of antibody maturation. The limiting antigen avidity enzyme immunoassay (LAg EIA) is widely used with HIV viral load (VL) in a recent infection testing algorithm (RITA) to improve classification of recent infection status, estimate population-level HIV incidence, and monitor trends in HIV transmission. A novel rapid test for recent HIV infection (RTRI), Asanté™, can determine HIV serostatus and HIV recency within minutes on a lateral flow device through visual assessment of test strip or reader device. We conducted a field-based laboratory evaluation of the RTRI among pregnant adolescent girls and young women (AGYW) attending antenatal clinics (ANC) in Malawi.We enrolled pregnant AGYW aged <25 years testing HIV-positive for the first time at their first ANC visit from 121 ANCs in four high-HIV burden districts. Consenting participants provided blood for recency testing using LAg EIA and RTRI, which were tested in central laboratories. Specimens with LAg EIA normalized optical density values ≤2.0 were classified as probable recent infections. RTRI results were based on: (1) visual assessment: presence of a long-term line (LT) indicating non-recent infection and absence of the line indicating recent infection; or (2) a reader; specimens with LT line intensity units <3.0 were classified as probable recent infections. VL was measured for specimens classified as a probable recent infections by either assay; those with HIV-1 RNA ≥1,000 copies/mL were classified as confirmed recent infections. We evaluated the performance of the RTRI by calculating correlation between RTRI and LAg EIA results, and percent agreement and kappa between RTRI and LAg EIA RITA results.Between November 2017 to June 2018, 380 specimens were available for RTRI evaluation; 376 (98.9%) were confirmed HIV-positive on RTRI. Spearman's rho between RTRI and LAg EIA was 0.72 indicating strong correlation. Percent agreement and kappa between RTRI- and LAg EIA-based RITAs were >90% and >0.65 respectively indicating substantial agreement between the RITAs.This was the first field evaluation of an RTRI in sub-Saharan Africa, which demonstrated good performance of the assay and feasibility of integrating RTRI into routine HIV testing services for real-time surveillance of recent HIV infection.

Impacts of Recent Infection Testing Integration into HIV Surveillance in Ekiti State, South West Nigeria: A Retrospective Cross Sectional Study

Background: Timely detection of recent HIV infections is critical in achieving the HIV epidemic. The aim of this study was to evaluate the effects of integrating the Recent Infection Testing Algorithm in HIV surveillance in Ekiti State, South West Nigeria. Method: Data from the Nigeria Medical Records System (NMRS)/National Data Repository (NDR) and Index Testing (IT) Services data capturing tools were abstracted for a retrospective cross-sectional study of 719 newly diagnosed HIV-positive cases who were screened for HIV incident infection using Asante rapid recency test kits between August 2020 and June 2022 at 5 selected recency testing health facilities. The venous blood (10 ml) of all the rapid Asante tested recent patients were collected into an EDTA tube and processed for viral load testing. The plasma level of HIV-1 RNA was quantified using the CAP/CTM and cobas 4800 platform at Obafemi Awolowo University Teaching Hospital PCR Laboratory Ife. Chi-square was used to characterize the recency status of the patients. A measure of the association was done using Chi-square, while the p-value of 0.05 was considered statistically significant. Results: The median age of the participants was 39 years. The result from the study showed that of the total number of 719 new cases of diagnosed HIV-positive, 626 of them were screened for rapid Test for Recency infection (RTRI) (87%). Overall, we found that 1.8% (11/626) of clients were classified as recent. The investigation also showed that from the index cases of the 11 confirmed recent infections, a total number of 125 additional positive cases were found. Conclusion: This result indicated a rise in the number of cases discovered in the State. Therefore, incorporating recency testing within regular HIV testing programs becomes essential in order to prioritize clients for index testing and provide useful information on transmission clusters.

HIV-1 Recent Infection Testing Algorithm With Antiretroviral Drug Detection to Improve Accuracy of Incidence Estimates.

HIV-1 incidence calculation currently includes recency classification by HIV-1 incidence assay and unsuppressed viral load (VL ≥ 1000 copies/mL) in a recent infection testing algorithm (RITA). However, persons with recent classification not virally suppressed and taking antiretroviral (ARV) medication may be misclassified. We used data from 13 African household surveys to describe the impact of an ARV-adjusted RITA on HIV-1 incidence estimates. HIV-seropositive samples were tested for recency using the HIV-1 Limiting Antigen (LAg)-Avidity enzyme immunoassay, HIV-1 viral load, ARVs used in each country, and ARV drug resistance. LAg-recent result was defined as normalized optical density values ≤1.5. We compared HIV-1 incidence estimates using 2 RITA: RITA1: LAg-recent + VL ≥ 1000 copies/mL and RITA2: RITA1 + undetectable ARV. We explored RITA2 with self-reported ARV use and with clinical history. Overall, 357 adult HIV-positive participants were classified as having recent infection with RITA1. RITA2 reclassified 55 (15.4%) persons with detectable ARV as having long-term infection. Those with detectable ARV were significantly more likely to be aware of their HIV-positive status (84% vs. 10%) and had higher levels of drug resistance (74% vs. 26%) than those without detectable ARV. RITA2 incidence was lower than RITA1 incidence (range, 0%-30% decrease), resulting in decreased estimated new infections from 390,000 to 341,000 across the 13 countries. Incidence estimates were similar using detectable or self-reported ARV (R2 > 0.995). Including ARV in RITA2 improved the accuracy of HIV-1 incidence estimates by removing participants with likely long-term HIV infection.

HIV Incidence by Male Circumcision Status From the Population-Based HIV Impact Assessment Surveys-Eight Sub-Saharan African Countries, 2015-2017.

Male circumcision (MC) offers men lifelong partial protection from heterosexually acquired HIV infection. The impact of MC on HIV incidence has not been quantified in nationally representative samples. Data from the population-based HIV impact assessments were used to compare HIV incidence by MC status in countries implementing voluntary medical MC (VMMC) programs. Data were pooled from population-based HIV impact assessments conducted in Eswatini, Lesotho, Malawi, Namibia, Tanzania, Uganda, Zambia, and Zimbabwe from 2015 to 2017. Incidence was measured using a recent infection testing algorithm and analyzed by self-reported MC status distinguishing between medical and nonmedical MC. Country, marital status, urban setting, sexual risk behaviors, and mean population HIV viral load among women as an indicator of treatment scale-up were included in a random-effects logistic regression model using pooled survey weights. Analyses were age stratified (15-34 and 35-59 years). Annualized incidence rates and 95% confidence intervals (CIs) and incidence differences were calculated between medically circumcised and uncircumcised men. Men 15-34 years reporting medical MC had lower HIV incidence than uncircumcised men [0.04% (95% CI: 0.00% to 0.10%) versus 0.34% (95% CI: 0.10% to 0.57%), respectively; P value = 0.01]; whereas among men 35-59 years, there was no significant incidence difference [1.36% (95% CI: 0.32% to 2.39%) versus 0.55% (95% CI: 0.14% to 0.67%), respectively; P value = 0.14]. Medical MC was associated with lower HIV incidence in men aged 15-34 years in nationally representative surveys in Africa. These findings are consistent with the expected ongoing VMMC program impact and highlight the importance of VMMC for the HIV response in Africa.

Experiences and lessons learned from the real-world implementation of an HIV recent infection testing algorithm in three routine service-delivery settings in Kenya and Zimbabwe

IntroductionTesting for recent HIV infection can distinguish recently acquired infection from long-standing infections. Given current interest in the implementation of recent infection testing algorithms (RITA), we report our experiences in implementing a RITA in three pilot studies and highlight important issues to consider when conducting recency testing in routine settings.MethodsWe applied a RITA, incorporating a limited antigen (LAg) avidity assay, in different routine HIV service-delivery settings in 2018: antenatal care clinics in Siaya County, Kenya, HIV testing and counselling facilities in Nairobi, Kenya, and female sex workers clinics in Zimbabwe. Discussions were conducted with study coordinators, laboratory leads, and facility-based stakeholders to evaluate experiences and lessons learned in relation to implementing recency testing.ResultsIn Siaya County 10/426 (2.3%) of women testing HIV positive were classified as recent, compared to 46/530 (8.7%) of women and men in Nairobi and 33/313 (10.5%) of female sex workers in Zimbabwe. Across the study setting, we observed differences in acceptance, transport and storage of dried blood spot (DBS) or venous blood samples. For example, the acceptance rate when testing venous blood was 11% lower than when using DBS. Integrating our study into existing services ensured a quick start of the study and kept the amount of additional resources required low. From a laboratory perspective, the LAg avidity assay was initially difficult to operationalise, but developing a network of laboratories and experts to work together helped to improve this. A challenge that was not overcome was the returning of RITA test results to clients. This was due to delays in laboratory testing, the need for multiple test results to satisfy the RITA, difficulties in aligning clinic visits, and participants opting not to return for test results.ConclusionWe completed three pilot studies using HIV recency testing based on a RITA in Kenya and Zimbabwe. The main lessons we learned were related to sample collection and handling, LAg avidity assay performance, integration into existing services and returning of test results to participants. Our real-world experience could provide helpful guidance to people currently working on the implementation of HIV recency testing in sub-Saharan Africa.

Evidence of an untamed HIV epidemic among MSM and TGW in Rio de Janeiro, Brazil: a 2018 to 2020 cross-sectional study using recent infection testing.

IntroductionMonitoring the HIV epidemic and identifying populations among whom HIV is spreading is critical. We aimed to provide an estimate of the annualized HIV incidence rate using recency testing among cisgender men who have sex with men (MSM) and transgender women (TGW) at a reference centre in Rio de Janeiro, Brazil.MethodsWe evaluated MSM and TGW who sought HIV testing at the Evandro Chagas National Institute of Infectious Diseases‐FIOCRUZ between March 2018 and January 2020. The Limiting Avidity assay (LAg) as part of a recent infection testing algorithm (RITA) was employed to identify recent infections (those with a normalized optical density ≤1.5 in the LAg that met all RITA criteria) among those who tested positive for HIV and the annualized HIV incidence was estimated.Results and discussionOut of 3053 individuals assessed, 2591 (84.9%) were HIV negative and 462 (15.1%) were living with HIV. Among these, 302 (65.4%) with stored samples available were evaluated and 73/302 (24.2%) were classified as recent infections. The annualized incidence rate estimate using a false recency rate of zero was 7.35% (95% CI 5.76% to 9.25%).ConclusionsOur results suggest that the HIV epidemic in Rio de Janeiro, Brazil, continues to disproportionately burden vulnerable populations, including MSM and TGW despite the existence and availability of effective preventive and therapeutic interventions.

Epidemiological factors associated with recent HIV infection among newly-diagnosed cases in Singapore, 2013\u20132017

BackgroundEarly diagnosis is crucial in securing optimal outcomes in the HIV care cascade. Recent HIV infection (RHI) serves as an indicator of early detection in the course of HIV infection. Surveillance of RHI is important in uncovering at-risk groups in which HIV transmission is ongoing. The study objectives are to estimate the proportion of RHI among persons newly-diagnosed in 2013–2017, and to elucidate epidemiological factors associated with RHI in Singapore.MethodsAs part of the National HIV Molecular Surveillance Programme, residual plasma samples of treatment-naïve HIV-1 positive individuals were tested using the biotinylated peptide-capture enzyme immunoassay with a cutoff of normalized optical density ≤ 0.8 for evidence of RHI. A recent infection testing algorithm was applied for the classification of RHI. We identified risk factors associated with RHI using logistic regression analyses.ResultsA total of 701 newly-diagnosed HIV-infected persons were included in the study. The median age at HIV diagnosis was 38 years (interquartile range, 28–51). The majority were men (94.2%), and sexual route was the predominant mode of HIV transmission (98.3%). Overall, 133/701 (19.0, 95% confidence interval [CI] 16.2–22.0%) were classified as RHI. The proportions of RHI in 2015 (31.1%) and 2017 (31.0%) were significantly higher than in 2014 (11.2%). A significantly higher proportion of men having sex with men (23.4, 95% CI 19.6–27.6%) had RHI compared with heterosexual men (11.1, 95% CI 7.6–15.9%). Independent factors associated with RHI were: age 15–24 years (adjusted odds ratio [aOR] 4.18, 95% CI 1.69–10.31) compared with ≥55 years; HIV diagnosis in 2015 (aOR 2.36, 95% CI 1.25–4.46) and 2017 (aOR 2.52, 95% CI 1.32–4.80) compared with 2013–2014; detection via voluntary testing (aOR 1.91, 95% CI 1.07–3.43) compared with medical care; and self-reported history of HIV test(s) prior to diagnosis (aOR 1.72, 95% CI 1.06–2.81).ConclusionAlthough there appears to be an increasing trend towards early diagnosis, persons with RHI remain a minority in Singapore. The strong associations observed between modifiable behaviors (voluntary testing and HIV testing history) and RHI highlight the importance of increasing the accessibility to HIV testing for at-risk groups.

Estimating HIV incidence in the Akwa Ibom AIDS indicator survey (AKAIS), Nigeria using the limiting antigen avidity recency assay.

IntroductionHIV incidence estimates are important to characterize the status of an epidemic, identify locations and populations at high risk and to guide and evaluate HIV prevention interventions. We used the limiting antigen avidity assay (LAg) as part of a recent infection testing algorithm to estimate HIV incidence in the Akwa Ibom AIDS Indicator Survey (AKAIS), Nigeria.MethodsIn 2017, AKAIS, a cross‐sectional population‐based study was conducted at the household (HH) level in 31 local government areas (LGAs) of Akwa Ibom state. Of the 8963 participants aged ≥15 years who were administered questionnaires for demographic and behavioural data, 8306 consented to HIV rapid testing. Whole‐blood specimens were collected from 394 preliminary HIV‐seropositive individuals for CD4+ cell count determination and plasma storage. Samples were shipped to a central quality laboratory for HIV confirmatory testing and viral load determination. A total of 370 HIV‐positive specimens were tested for the recent HIV infection using the LAg assay.ResultsOf the 8306 consenting adults, the HIV prevalence was 4.8%. Of the 370 HIV‐positive samples tested for HIV recency, the median age was 35 years, 48.8% had CD4+ cell count >500/mm3 and 81.3% was not virally suppressed. Viral suppression was greater among females (21%) than for males (13%). A total of 11 specimens were classified as recent based on the LAg assay and HIV viral load ≥1000 copies/mL. The weighted, adjusted HIV‐1 incidence was 0.41/100 person‐years (95% CI 0.16 to 0.66); translating to 13,000 new cases of HIV infections annually in Akwa Ibom, a state with a population of 5.5 million. The HIV incidence rate was similar in females and males (0.41% and 0.42% respectively). The incidence rate was the highest among participants aged 15 to 49 years (0.44%, 95% CI 0.15 to 0.74) translating to 11,000 new infections annually, about 85% of all new infections in the state.ConclusionsThe finding of the high HIV incidence among the 15 to 49‐year age group calls for renewed and innovative efforts to prevent HIV infection among young adults in Akwa Ibom state.