Holguín, Á. (África)

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    Utility Of POC Xpert HIV-1 Tests For Detection-Quantifcation Of Complex HIV Recombinants Using Dried Blood Spots From Kinshasa, D. R. Congo
    (Springer Science and Business Media LLC, 2019) Carlos-Chillerón, S. (Silvia); Holguín, Á. (África); Fernández-Alonso, M. (Miriam); Rubio-Garrido, M. (Marina); Barquín, D. (David); Reina, G. (Gabriel); Ndarabu, A. (Adolphe)
    Point-of-Care (POC) molecular assays improve HIV infant diagnosis and viral load (VL) quantification in resource-limited settings. We evaluated POC performance in Kinshasa (Democratic Republic of Congo), with high diversity of HIV-1 recombinants. In 2016, 160 dried blood samples (DBS) were collected from 85 children (60 HIV-, 18 HIV+, 7 HIV-exposed) and 75 HIV+ adults (65 treated, 10 naive) at Monkole Hospital (Kinshasa). We compared viraemia with Cepheid-POC-Xpert-HIV-1VL and the non-POC-COBAS®AmpliPrep/COBAS®TaqMan®HIV-1-Testv2 in all HIV+, carrying 72.4%/7.2% HIV-1 unique/complex recombinant forms (URF/CRF). HIV-1 infection was confirmed in 14 HIV+ children by Cepheid-POC-Xpert-HIV-1Qual and in 70 HIV+ adults by both Xpert-VL and Roche-VL, identifying 8 false HIV+ diagnosis performed in DRC (4 adults, 4 children). HIV-1 was detected in 95.2% and 97.6% of 84 HIV+ samples by Xpert-VL and Roche-VL, respectively. Most (92.9%) HIV+ children presented detectable viraemia by both VL assays and 74.3% or 72.8% of 70 HIV+ adults by Xpert or Roche, respectively. Both VL assays presented high correlation (R2 = 0.89), but showing clinical relevant ≥0.5 log VL differences in 15.4% of 78 cases with VL within quantification range by both assays. This is the first study confirming the utility of Xpert HIV-1 tests for detection-quantification of complex recombinants currently circulating in Kinshasa.
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    Immune surveillance for six vaccinable pathogens using paired plasma and dried blood spots in HIV infected and uninfected children in Kinshasa
    (2022) Rodríguez-Donís, M. (Marcelino); Holguín, Á. (África); Galán, J.C.; Rubio-Garrido, M. (Marina); Rodríguez-Galet, A. (Ana); Reina, G. (Gabriel); Ndarabu, A. (Adolphe); Valadés-Alcaraz, A. (Ana)
    Child vaccination reduces infant mortality rates. HIV-infected children present higher risk of diseases than non-infected. We report the protection coverage rates for 6 vaccine-preventable diseases in a paediatric population from the Democratic Republic of the Congo (DRC) and the impact of HIV infection, providing the first data on the validity of dried blood samples (DBS) to monitor the immune protection. During 2016-2018 DBS from 143 children/adolescents were collected in Kinshasa (DRC), being 52 HIV-infected. Forty-two had a paired plasma sample. Protective IgG was quantified (VirClia-IgG,VIRCELL) to obtain the optimal cut-off in IgG detection in DBS. ROC curves were generated with R software and statistical analyses with Stata. Protective IgG levels varied across pathogens, not reaching herd immunity. HIV-infected presented lower vaccine protection than uninfected for all analyzed pathogens, except rubella, with statistically significant differences for measles (30.8% vs. 53.8%; p = 0.008) and tetanus (3.8% vs. 22%; p = 0.0034). New cut-offs were calculated when using DBS to improve test performance. We reinforce the necessity to increase pediatric vaccination coverage in Kinshasa, especially in HIV seropositive, with less capacity to maintain adequate antibody levels. DBS were useful to monitor vaccination coverage in seroprevalence studies in resource-limited settings, after optimizing the cut-off value for each pathogen.
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    High pre‐Delta and early‐Omicron SARS‐CoV‐2 seroprevalence detected in dried blood samples from Kinshasa (D.R. Congo)
    (Wiley, 2024) Carlos-Chillerón, S. (Silvia); Burgueño, E. (Eduardo); Holguín, Á. (África); Mbikayi, S. (Samclide); Pina-Sanchez, M. (Manuel); Martínez-de-Aguirre, P. (Paula); Chiva, L. (Luis); Reina, G. (Gabriel); Mbamba-Baluanda, C.T. (Cèline Tendobi)
    Studies on the impact of the COVID‐19 pandemic in sub‐Saharan Africa have yielded varying results, although authors universally agree the real burden surpasses reported cases. The primary objective of this study was to determine SARS‐CoV‐2 seroprevalence among patients attending Monkole Hospital in Kinshasa (D.R. Congo). The secondary objective was to evaluate the analytic performance of two chemiluminescence platforms: Elecsys® (Roche) and VirClia® (Vircell) on dried blood spot samples (DBS). The study population (N = 373) was recruited in two stages: a mid‐2021 blood donor cohort (15.5% women) and a mid‐2022 women cohort. Crude global seroprevalence was 61% (53.9%–67.8%) pre‐Delta in 2021 and 90.2% (84.7%–94.2%) post‐Omicron in 2022. Anti‐spike (S) antibody levels significantly increased from 53.1 (31.8–131.3) U/mL in 2021 to 436.5 (219.3–950.5) U/mL in 2022 and were significantly higher above 45 years old in the 2022 population. Both platforms showed good analytic performance on DBS samples: sensitivity was 96.8% for IgG (antiN/S) (93.9%–98.5%) and 96.0% (93.0%–98.0%) for anti‐S quantification. These results provide additional support for the notion that exposure to SARS‐CoV‐2 is more widespread than indicated by case‐based surveillance and will be able to guide the pandemic response and strategy moving forward. Likewise, this study contributes evidence to the reliability of DBS as a tool for serological testing and diagnosis in resource‐limited settings.
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    High drug resistance levels could compromise the control of HIV infection in paediatric and adolescent population in Kinshasa, the Democratic Republic of Congo.
    (2021) Carlos-Chillerón, S. (Silvia); Holguín, Á. (África); Rubio-Garrido, M. (Marina); Rodríguez-Galet, A. (Ana); Barquín, D. (David); Reina, G. (Gabriel); Ndarabu, A. (Adolphe); Valadés-Alcaraz, A. (Ana)
    Background The inadequacy of HIV viraemia and resistance monitoring in Africa leads to uncontrolled circulation of HIV strains with drug resistance mutations (DRM), compromising antiretroviral therapy (ART) effectiveness. This study describes the DRM prevalence and its therapeutic impact in HIV-infected pediatric patients from Kinshasa (Democratic Republic of Congo, DRC). Methods From 2016-2018, dried blood were collected from 71 HIV-infected children and adolescents under ART in two hospitals in Kinshasa for HIV-1 DRM pol analysis, predicted ARV-susceptibility by Stanford and phylogenetic characterization. Results HIV-1 sequences were recovered from 55 children/adolescents with 14 years of median-age. All had received nucleoside and non-nucleoside reverse transcriptase inhibitors (NRTI, NNRTI), 9.1% protease inhibitors (PI) and only one integrase inhibitor (INI). Despite the use of ART, 89.1% showed virological failure and 67.3% carried viruses with major-DRM to one (12.7%), two (47.3%), or three (5.5%) ARV-families. Most children/adolescents harbored DRM to NNRTI (73.5%) or NRTI (61.2%). Major-DRM to PI was present in 8.3% and minor-DRM to INI in 15%. Dual-class-NRTI+NNRTI resistance appeared in 53.1% of patients. Viruses presented high/intermediate resistance to nevirapine (72.9% patients), efavirenz (70.9%), emtricitabine/lamivudine (47.9%), rilpivirine (41.7%), etravirine (39.6%), doravidine (33.3%), zidovudine (22.9%), among others. Most participants were susceptible to INI and PI. Great diversity of variants was found, with a high rate (40%) of unique recombinants. Conclusion The high DRM prevalence observed among HIV-infected children and adolescents in Kinshasa could compromise the 95-95-95-UNAIDS targets in the DRC. It also reinforces the need for routine resistance monitoring for optimal rescue therapy election in this vulnerable population to control the spread of resistant HIV in the country.
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    HIV-1 diagnosis using dried blood spots from patients in Kinshasa, DRC: a tool to detect misdiagnosis and achieve World Health Organization 2030 targets
    (Elsevier, 2021) Carlos-Chillerón, S. (Silvia); Makonda, B. (Benit); Holguín, Á. (África); Fernández-Alonso, M. (Miriam); Rubio-Garrido, M. (Marina); Barquín, D. (David); Reina, G. (Gabriel); Ndarabu, A. (Adolphe)
    Introduction: Currently, only 54% of the population of the Democratic Republic of the Congo (DRC) know their HIV status. The aim of this study was to detect HIV misdiagnosis from rapid diagnostic tests (RDT) and to evaluate serological immunoassays using dried blood spots (DBS) from patients in Kinshasa, DRC. Methods: Between 2016 and 2018, 365 DBS samples were collected from 363 individuals and shipped to Spain. The samples were from people with a new HIV positive (n = 123) or indeterminate (n = 23) result, known HIV-positive patients (n = 157), and a negative control group (n = 62). HIV serology was performed using Elecsys HIV combi PT (Roche), VIDAS HIV Duo Quick (BioMérieux), and Geenius (Bio- Rad). In addition, HIV RNA detection was performed in all samples using the COBAS AmpliPrep/COBAS Taqman HIV-1 Test 2.0 (Roche). Results: Overall, 272 samples were found to be positive and 93 to be negative for HIV serology. The sensitivity was 100% for both Elecsys and VIDAS techniques, but specificity was slightly higher for the VIDAS test: 100% (96.1–100%) vs 98.9% (94.1–99.9%). Of the 23 indeterminate cases using RDT, only three cases were true-positives with a detectable viral load. Eleven samples out of the 280 classified as positive by RDT corresponded to nine patients who had received a false diagnosis of HIV through RDT (3.9%); six of them had been on antiretroviral therapy for at least 2 years. Conclusions: Elecsys HIV combi PT and VIDAS HIV Duo Quick immunoassays showed high sensitivity and specificity when using DBS. RDT-based serological diagnosis can lead to HIV misdiagnosis with personal and social consequences in sub-Saharan Africa.
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    Impact of storage time in dried blood samples (DBS) and dried plasma samples (DPS) for point-of-care hepatitis C virus (HCV) RNA quantification and HCV core antigen detection
    (2023) Holguín, Á. (África); Troyano-Hernáez, P. (Paloma); Galán, J.C. (Juan Carlos); Reina-González, G. (Gabriel); Gea, F. (Francisco); Herrador, P. (Pedro); Romero-Hernández, B.; Albillos, A. (Agustín)
    The scale-up of hepatitis C virus (HCV) diagnosis and treatment requires affordable and simple tools to improve access to care, especially in low- and middle-income settings with limited infrastructure or high-risk populations. Dried blood and plasma samples (DBS and DPS) are useful alternative for hepatitis C detection in settings lacking adequate infrastructure. We evaluated the performance of DBS and DPS vs plasma in a point-of-care HCV RNA quantitative assay (Xpert HCV Viral Load-Cepheid), and compared HCV core antigen (HCVcAg) detection by the Architect HCV core antigen assay (Abbott) in DBS vs serum. The dried samples were stored at room temperature for different storage times to reproduce the time from sampling to testing in settings with centralized diagnosis or when testing mobile populations. HCV RNA quantification in DBS and DPS presented 100% sensitivity and specificity and a high correlation for up to 3 months of storage. HCV viremia showed a mean decrease of 0.5 log(10) IU/mL (DBS) and 0.3 log(10) IU/mL (DPS) for storage times up to 1 month. Architect HCVcAg detection presented high sensitivity/specificity (96%/100%) in DBS tested immediately after sampling, decreasing to 86% sensitivity after 7 days of storage. However, sensitivity increased when an optimized cut-off was applied for each storage time. We conclude that DBS and DPS are suitable samples for HCV RNA detection and quantification, being DPS more reliable for shorter storage times. DBS can be also used for HCVcAg qualitative detection and the sensitivity can be increased when adjusting the cut-off values. IMPORTANCE Hepatitis C infection remains a global burden despite the effectiveness of antivirals. In the WHO roadmap to accomplish HCV elimination by 2030, HCV diagnosis is one of the main targets. However, identifying patients in resource-limited settings and high-risk populations with limited access to healthcare remains a challenge and requires innovative approaches that allow decentralized testing. The significance of our research is in verifying the good performance of dried samples for HCV diagnosis using two different diagnostics assays and considering the effect of room temperature storage in this sample format. We confirmed dried samples are an interesting alternative for HCV screening and reflex testing in resource-limited settings or high-risk populations.
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    Current and historic HIV‑1 molecular epidemiology in paediatric and adult population from Kinshasa in the Democratic Republic of Congo
    (2020) Carlos-Chillerón, S. (Silvia); Holguín, Á. (África); Galán, J.C.; Rubio-Garrido, M. (Marina); González‑Alba, J.M. (José María); Barquín, D. (David); Reina, G. (Gabriel); Ndarabu, A. (Adolphe)
    HIV-1 diversity may impact monitoring and vaccine development. We describe the most recent data of HIV-1 variants and their temporal trends in the Democratic Republic of Congo (DRC) from 1976 to 2018 and in Kinshasa from 1983–2018. HIV-1 pol sequencing from dried blood collected in Kinshasa during 2016–2018 was done in 340 HIV-infected children/adolescents/adults to identify HIV-1 variants by phylogenetic reconstructions. Recombination events and transmission clusters were also analyzed. Variant distribution and genetic diversity were compared to historical available pol sequences from the DRC in Los Alamos Database (LANL). We characterized 165 HIV-1 pol variants circulating in Kinshasa (2016–2018) and compared them with 2641 LANL sequences from the DRC (1976–2012) and Kinshasa (1983–2008). During 2016–2018 the main subtypes were A (26.7%), G (9.7%) and C (7.3%). Recombinants accounted for a third of infections (12.7%/23.6% Circulant/Unique Recombinant Forms). We identifed the frst CRF47_BF reported in Africa and four transmission clusters. A signifcant increase of subtype A and sub-subtype F1 and a signifcant reduction of sub-subtype A1 and subtype D were observed in Kinshasa during 2016–2018 compared to variants circulating in the city from 1983 to 2008. We provide unique and updated information related to HIV-1 variants currently circulating in Kinshasa, reporting the temporal trends of subtypes/CRF/URF during 43 years in the DRC, and providing the most extensive data on children/adolescents.