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1.
PLOS Glob Public Health ; 4(4): e0003030, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38573931

RESUMEN

As antiretroviral treatment (ART) coverage for people living with HIV (PLHIV) increases, HIV programmes require up-to-date information about evolving HIV risk behaviour and transmission risk, including those with low-level viremia (LLV; >50 to ≤1000 copies/mL), to guide prevention priorities. We aimed to assess differences in sexual risk behaviours, distribution of viral load (VL) and proportion of transmission across PLHIV subgroups. We analysed data from Population-based HIV Impact Assessment surveys in 14 sub-Saharan African countries during 2015-2019. We estimated adjusted prevalence ratios (aPR) of self-reported HIV high-risk behaviour (multiple partners and condomless sex) across cascade stages via generalised estimation equations. We modelled the proportions of transmission from each subgroup using relative self-reported sexual risk, a Hill function for transmission rate by VL, and proportions within cascade stages from surveys and UNAIDS country estimates for 2010-2020. Compared to PLHIV with undetectable VL (≤50 copies/mL), undiagnosed PLHIV (aPR women: 1.28 [95% CI: 1.08-1.52]; men: 1.61 [1.33-1.95]) and men diagnosed but untreated (2.06 [1.52-2.78]) were more likely to self-report high-risk sex. High-risk behaviour was not significantly associated with LLV. Mean VL was similar among undiagnosed, diagnosed but untreated, and on ART but non-suppressed sub-groups. Across surveys, undiagnosed and diagnosed but untreated contributed most to transmission (40-91% and 1-41%, respectively), with less than 1% from those with LLV. Between 2010 and 2020, the proportion of transmission from individuals on ART but non-suppressed increased. In settings with high ART coverage, effective HIV testing, ART linkage, and retention remain priorities to reduce HIV transmission. Persons with LLV are an increasing share of PLHIV but their contribution to HIV transmission was small. Improving suppression among PLHIV on ART with VL ≥1000 copies/mL will become increasingly important.

2.
PLoS One ; 18(6): e0275560, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37363921

RESUMEN

BACKGROUND: We examined the epidemiology and transmission potential of HIV population viral load (VL) in 12 sub-Saharan African countries. METHODS: We analyzed data from Population-based HIV Impact Assessments (PHIAs), large national household-based surveys conducted between 2015 and 2019 in Cameroon, Cote d'Ivoire, Eswatini, Kenya, Lesotho, Malawi, Namibia, Rwanda, Tanzania, Uganda, Zambia, and Zimbabwe. Blood-based biomarkers included HIV serology, recency of HIV infection, and VL. We estimated the number of people living with HIV (PLHIV) with suppressed viral load (<1,000 HIV-1 RNA copies/mL) and with unsuppressed viral load (viremic), the prevalence of unsuppressed HIV (population viremia), sex-specific HIV transmission ratios (number female incident HIV-1 infections/number unsuppressed male PLHIV per 100 persons-years [PY] and vice versa) and examined correlations between a variety of VL metrics and incident HIV. Country sample sizes ranged from 10,016 (Eswatini) to 30,637 (Rwanda); estimates were weighted and restricted to participants 15 years and older. RESULTS: The proportion of female PLHIV with viral suppression was higher than that among males in all countries, however, the number of unsuppressed females outnumbered that of unsuppressed males in all countries due to higher overall female HIV prevalence, with ratios ranging from 1.08 to 2.10 (median: 1.43). The spatial distribution of HIV seroprevalence, viremia prevalence, and number of unsuppressed adults often differed substantially within the same countries. The 1% and 5% of PLHIV with the highest VL on average accounted for 34% and 66%, respectively, of countries' total VL. HIV transmission ratios varied widely across countries and were higher for male-to-female (range: 2.3-28.3/100 PY) than for female-to-male transmission (range: 1.5-10.6/100 PY). In all countries mean log10 VL among unsuppressed males was higher than that among females. Correlations between VL measures and incident HIV varied, were weaker for VL metrics among females compared to males and were strongest for the number of unsuppressed PLHIV per 100 HIV-negative adults (R2 = 0.92). CONCLUSIONS: Despite higher proportions of viral suppression, female unsuppressed PLHIV outnumbered males in all countries examined. Unsuppressed male PLHIV have consistently higher VL and a higher risk of transmitting HIV than females. Just 5% of PLHIV account for almost two-thirds of countries' total VL. Population-level VL metrics help monitor the epidemic and highlight key programmatic gaps in these African countries.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Humanos , Masculino , Femenino , Infecciones por VIH/tratamiento farmacológico , Viremia/tratamiento farmacológico , Carga Viral , Estudios Seroepidemiológicos , Lesotho , Zimbabwe , Fármacos Anti-VIH/uso terapéutico
3.
Emerg Infect Dis ; 28(13): S59-S68, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36502414

RESUMEN

The US President's Emergency Plan for AIDS Relief (PEPFAR) supports molecular HIV and tuberculosis diagnostic networks and information management systems in low- and middle-income countries. We describe how national programs leveraged these PEPFAR-supported laboratory resources for SARS-CoV-2 testing during the COVID-19 pandemic. We sent a spreadsheet template consisting of 46 indicators for assessing the use of PEPFAR-supported diagnostic networks for COVID-19 pandemic response activities during April 1, 2020, to March 31, 2021, to 27 PEPFAR-supported countries or regions. A total of 109 PEPFAR-supported centralized HIV viral load and early infant diagnosis laboratories and 138 decentralized HIV and TB sites reported performing SARS-CoV-2 testing in 16 countries. Together, these sites contributed to >3.4 million SARS-CoV-2 tests during the 1-year period. Our findings illustrate that PEPFAR-supported diagnostic networks provided a wide range of resources to respond to emergency COVID-19 diagnostic testing in 16 low- and middle-income countries.


Asunto(s)
COVID-19 , Infecciones por VIH , Humanos , Prueba de COVID-19 , Patología Molecular , Pandemias , SARS-CoV-2 , COVID-19/diagnóstico
4.
J Int AIDS Soc ; 25 Suppl 4: e26005, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36176030

RESUMEN

INTRODUCTION: Achieving optimal HIV outcomes, as measured by global 90-90-90 targets, that is awareness of HIV-positive status, receipt of antiretroviral (ARV) therapy among aware and viral load (VL) suppression among those on ARVs, respectively, is critical. However, few data from sub-Saharan Africa (SSA) are available on older people (50+) living with HIV (OPLWH). We examined 90-90-90 progress by age, 15-49 (as a comparison) and 50+ years, with further analyses among 50+ (55-59, 60-64, 65+ vs. 50-54), in 13 countries (Cameroon, Cote d'Ivoire, Eswatini, Ethiopia, Kenya, Lesotho, Malawi, Namibia, Rwanda, Tanzania, Uganda, Zambia and Zimbabwe). METHODS: Using data from nationally representative Population-based HIV Impact Assessments, conducted between 2015and 2019, participants from randomly selected households provided demographic and clinical information and whole blood specimens for HIV serology, VL and ARV testing. Survey weighted outcomes were estimated for 90-90-90 targets. Country-specific Poisson regression models examined 90-90-90 variation among OPLWH age strata. RESULTS: Analyses included 24,826 HIV-positive individuals (15-49 years: 20,170; 50+ years: 4656). The first, second and third 90 outcomes were achieved in 1, 10 and 5 countries, respectively, by those aged 15-49, while OPLWH achieved outcomes in 3, 13 and 12 countries, respectively. Among those aged 15-49, women were more likely to achieve 90-90-90 targets than men; however, among OPLWH, men were more likely to achieve first and third 90 targets than women, with second 90 achievement being equivalent. Country-specific 90-90-90 regression models among OPLWH demonstrated minimal variation by age stratum across 13 countries. Among OLPWH, no first 90 target differences were noted by age strata; three countries varied in the second 90 by older age strata but not in a consistent direction; one country showed higher achievement of the third 90 in an older age stratum. CONCLUSIONS: While OPLWH in these 13 countries were slightly more likely than younger people to be aware of their HIV-positive status (first 90), this target was not achieved in most countries. However, OPLWH achieved treatment (second 90) and VL suppression (third 90) targets in more countries than PLWH <50. Findings support expanded HIV testing, prevention and treatment services to meet ongoing OPLWH health needs in SSA.


Asunto(s)
Infecciones por VIH , Adolescente , Adulto , Anciano , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Malaui , Masculino , Persona de Mediana Edad , Pruebas Serológicas , Encuestas y Cuestionarios , Carga Viral , Adulto Joven
5.
BMC Public Health ; 22(1): 132, 2022 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-35045854

RESUMEN

BACKGROUND: Little is known about HIV in South Sudan and even less about HIV among female sex workers (FSW). We characterized progress towards UNAIDS 90-90-90 targets among female sex workers (FSW) and sexually exploited female adolescents in Juba and Nimule, South Sudan. METHODS: We conducted a biobehavioral survey of FSW and sexually exploited female adolescents using respondent-driven sampling (RDS) in Juba (November 2015-March 2016) and in Nimule (January-March 2017) to estimate achievements toward the UNAIDS 90-90-90 targets (90% of HIV-positive individuals know their status; of these, 90% are receiving antiretroviral therapy [ART]; and of these, 90% are virally suppressed). Eligibility criteria were girls and women who were aged ≥15 years; spoke English, Juba Arabic, or Kiswahili; received money, goods, or services in exchange for sex in the past 6 months; and resided, worked, or socialized in the survey city for ≥1 month. Data were weighted for RDS methods. RESULTS: We sampled 838 FSW and sexually exploited female adolescents in Juba (HIV-positive, 333) and 409 in Nimule (HIV-positive, 108). Among HIV-positive FSW and sexually exploited female adolescents living in Juba, 74.8% self-reported being aware of their HIV status; of these, 73.3% self-reported being on ART; and of these, 62.2% were virally suppressed. In Nimule, 79.5% of FSW and sexually exploited female adolescents living with HIV self-reported being aware of their HIV status; of these, 62.9% self-reported being on ART; and of these, 75.7% were virally suppressed. CONCLUSIONS: Although awareness of HIV status is the lowest of the 90-90-90 indicators in many countries, treatment uptake and viral suppression were lowest among FSW and sexually exploited female adolescents in South Sudan. Differentiated service delivery facilitate linkage to and retention on treatment in support of attainment of viral suppression.


Asunto(s)
Infecciones por VIH , Trabajadores Sexuales , Adolescente , Estudios Transversales , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Prevalencia , Sudán del Sur/epidemiología
6.
Pediatr Infect Dis J ; 40(11): 1011-1018, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34382613

RESUMEN

BACKGROUND: Control of the pediatric HIV epidemic is hampered by gaps in diagnosis and linkage to effective treatment. The 2015-2016 Malawi Population-based HIV impact assessment data were analyzed to identify gaps in pediatric HIV diagnosis, treatment, and viral load suppression. METHODS: In half of the surveyed households, children ages ≥18 months to <15 years were tested using the national HIV rapid test algorithm. Children ≤18 months reactive by the initial rapid test underwent HIV total nucleic acid polymerase chain reaction confirmatory testing. Blood from HIV-positive children was tested for viral load (VL) and presence of antiretroviral drugs. HIV diagnosis and antiretroviral treatment (ART) use were defined using guardian-reporting or antiretroviral detection. RESULTS: Of the 6166 children tested, 99 were HIV-positive for a prevalence of 1.5% (95% confidence intervals [CI]: 1.1-1.9) and 8.0% (95% CI: 5.6-10.5) among HIV-exposed children. The prevalence of 1.5% was extrapolated to a national estimate of 119,501 (95% CI: 89,028-149,974) children living with HIV (CLHIV), of whom, 30.7% (95% CI: 20.3-41.1) were previously undiagnosed. Of the 69.3% diagnosed CLHIV, 86.1% (95% CI: 76.8-95.6) were on ART and 57.9% (95% CI: 41.4-74.4) of those on ART had suppressed VL (<1000 HIV RNA copies/mL). Among all CLHIV, irrespective of HIV diagnosis or ART use, 57.7% (95% CI: 45.0-70.5) had unsuppressed VL. CONCLUSIONS: Critical gaps in HIV diagnosis in children persist in Malawi. The large proportion of CLHIV with unsuppressed VL reflects gaps in diagnosis and need for more effective first- and second-line ART regimens and adherence interventions.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Evaluación del Impacto en la Salud/métodos , Población , Carga Viral/efectos de los fármacos , Adolescente , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Composición Familiar , Femenino , Infecciones por VIH/epidemiología , Humanos , Lactante , Recién Nacido , Malaui/epidemiología , Masculino , Prevalencia , Resultado del Tratamiento
7.
J Acquir Immune Defic Syndr ; 88(3): 272-281, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34321414

RESUMEN

OBJECTIVE: We present findings from the nationally representative Zimbabwe Population-based HIV Impact Assessment that characterize Zimbabwe's progress toward the Joint United Nations Programme on HIV/AIDS 90-90-90 targets. DESIGN: We conducted a cross-sectional household survey. METHODS: Consenting adults and children in the household were eligible to participate in Zimbabwe Population-based HIV Impact Assessment (October 2015-August 2016). Participants completed face-to-face interviews and provided blood for HIV, CD4, viral load, and syphilis testing. Viral load suppression (VLS) was defined as HIV RNA <1000 copies/mL. HIV-positive specimens were tested for the presence of selected antiretroviral drugs. Data were weighted. Analysis was restricted to HIV-positive adults aged 15-64 years. RESULTS: We enrolled 11,098 men and 14,033 women aged 15-64 years. HIV prevalence was 14.1%. Of those living with HIV, 76.8% (95% confidence interval [CI]: 74.9 to 78.7) were aware of their HIV status or had detectable antiretroviral levels. Of these, 88.4% (95% CI: 87.1 to 89.7) were receiving antiretroviral therapy (ART), and of these people, 85.3% (95% CI: 83.4 to 87.1) had VLS. Male sex age 15-34 years and having 1 or more sexual partners were associated with being unaware of one's HIV-positive status. Age <50 years and not taking cotrimoxazole were associated with being less likely to be being both aware and taking ART. Male sex, age <50 years, and taking cotrimoxazole were associated with being on ART but not having VLS. CONCLUSIONS: Zimbabwe has made great strides toward epidemic control. Focusing resources on case finding, particularly among men, people aged <35 years, and sexually active individuals can help Zimbabwe attain 90-90-90 targets.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Adolescente , Adulto , Niño , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Carga Viral , Adulto Joven , Zimbabwe/epidemiología
8.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S17-S27, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166309

RESUMEN

BACKGROUND: Conducting HIV surveys in resource-limited settings is challenging because of logistics, limited availability of trained personnel, and complexity of testing. We described the procedures and systems deemed critical to ensure high-quality laboratory data in the population-based HIV impact assessments and large-scale household surveys. METHODS: Laboratory professionals were engaged in every stage of the surveys, including protocol development, site assessments, procurement, training, quality assurance, monitoring, analysis, and reporting writing. A tiered network of household, satellite laboratories, and central laboratories, accompanied with trainings, optimized process for blood specimen collection, storage, transport, and real-time monitoring of specimen quality, and test results at each level proved critical in maintaining specimen integrity and high-quality testing. A plausibility review of aggregate merged data was conducted to confirm associations between key variables as a final quality check for quality of laboratory results. RESULTS: Overall, we conducted a hands-on training for 3355 survey staff across 13 surveys, with 160-387 personnel trained per survey on biomarker processes. Extensive training and monitoring demonstrated that overall, 99% of specimens had adequate volume and 99.8% had no hemolysis, indicating high quality. We implemented quality control and proficiency testing for testing, resolved discrepancies, verified >300 Pima CD4 instruments, and monitored user errors. Aggregate data review for plausibility further confirmed the high quality of testing. CONCLUSIONS: Ongoing engagement of laboratory personnel to oversee processes at all levels of the surveys is critical for successful national surveys. High-quality population-based HIV impact assessments laboratory data ensured reliable results and demonstrated the impact of HIV programs in 13 countries.


Asunto(s)
Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , VIH-1 , Ensayos de Aptitud de Laboratorios/normas , Países en Desarrollo , Monitoreo Epidemiológico , Encuestas Epidemiológicas , Humanos , Personal de Laboratorio/educación , Personal de Laboratorio/normas , Control de Calidad
9.
J Acquir Immune Defic Syndr ; 87(Suppl 1): S67-S72, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34166314

RESUMEN

BACKGROUND: In the population-based HIV impact assessment surveys, early infant diagnosis (EID) was provided to infants <18 months without a prior diagnosis. For the Namibia population-based HIV impact assessment (NAMPHIA), the GeneXpert platform was assessed for the feasibility of near POC EID testing compared with the standard Roche COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) platform. Quality assurance measures and turnaround time were compared to improve EID results reporting. METHODS: NAMPHIA participants were screened for HIV exposure using Determine HIV-1/2 rapid test; samples reactive on Determine received EID testing on the GeneXpert instrument and Xpert HIV-1 Qual assay using whole blood. Results were confirmed at the Namibia Institute of Pathology using dried blood spots on the Roche CAP/CTM platform per national guidelines. RESULTS: Of the 762 screened infants, 61 (8.0%) were Determine-reactive and considered HIV-exposed. Of the 61 exposed infants, 2 were found to be HIV-infected whereas 59 were negative on both GeneXpert and Roche platforms, achieving 100% concordance. Average turnaround time was 3.4 days for the Xpert HIV-1 Qual assay, and average time from collection to testing was 1.0 days for GeneXpert compared with 10.7 days for Roche. No samples failed using GeneXpert whereas 1 sample failed using Roche and was repeated. CONCLUSION: Quality POC EID testing is feasible in a national survey through extensive training and external quality assurance measures. The use of decentralized POC EID for national testing would provide rapid diagnosis and improve TATs which may prevent loss to follow-up, ensure linkage to care, and improve clinical outcomes for infants.


Asunto(s)
Monitoreo Epidemiológico , Infecciones por VIH/diagnóstico , Prueba de VIH/métodos , VIH-1 , Encuestas Epidemiológicas , Pruebas en el Punto de Atención , Países en Desarrollo , Femenino , Humanos , Lactante , Recién Nacido , Masculino
10.
MMWR Morb Mortal Wkly Rep ; 70(21): 775-778, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34043612

RESUMEN

One component of the Joint United Nations Programme on HIV/AIDS (UNAIDS) goal to end the HIV/AIDS epidemic by 2030, is that 95% of all persons receiving antiretroviral therapy (ART) achieve viral suppression.† Thus, testing all HIV-positive persons for viral load (number of copies of viral RNA per mL) is a global health priority (1). CDC and other U.S. government agencies, as part of the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), together with other stakeholders, have provided technical assistance and supported the cost for multiple countries in sub-Saharan Africa to expand viral load testing as the preferred monitoring strategy for clinical response to ART. The individual and population-level benefits of ART are well understood (2). Persons receiving ART who achieve and sustain an undetectable viral load do not transmit HIV to their sex partners, thereby disrupting onward transmission (2,3). Viral load testing is a cost-effective and sustainable programmatic approach for monitoring treatment success, allowing reduced frequency of health care visits for patients who are virally suppressed (4). Viral load monitoring enables early and accurate detection of treatment failure before immunologic decline. This report describes progress on the scale-up of viral load testing in eight sub-Saharan African countries from 2013 to 2018 and examines the trajectory of improvement with viral load testing scale-up that has paralleled government commitments, sustained technical assistance, and financial resources from international donors. Viral load testing in low- and middle-income countries enables monitoring of viral load suppression at the individual and population level, which is necessary to achieve global epidemic control. Although there has been substantial achievement in improving viral load coverage for all patients receiving ART, continued engagement is needed to reach global targets.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/virología , Vigilancia de la Población , Carga Viral , África del Sur del Sahara/epidemiología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos
11.
J Acquir Immune Defic Syndr ; 86(4): e97-e105, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33252546

RESUMEN

BACKGROUND: Early antiretroviral therapy (ART) is necessary for HIV epidemic control and depends on early diagnosis and successful linkage to care. Since 2014, annual household-based HIV testing and counseling and linkage services have been provided through the Chókwè Health and Demographic Surveillance System for residents testing HIV positive in this high HIV-burden district. METHODS: District-wide Test and Start [T&S, ART for all people living with HIV (PLHIV)] began in August 2016, supported by systematic interventions to improve linkage to care and treatment. Annual rounds (R) of random household surveys were conducted to assess trends in population prevalence of ART use and viral load suppression (<1000 viral RNA copies/mL). RESULTS: Between R1 (April 2014-April 2015) and R5 (April 2018-Mar 2019), 46,090 (67.2%) of 68,620 residents aged 15-59 years were tested for HIV at home at least once, and 3711 were newly diagnosed with HIV and provided linkage services. Population prevalence of current ART use among PLHIV increased from 65.0% to 87.5% between R1 and R5. ART population prevalence was lowest among men aged 25-34 years (67.8%) and women aged 15-24 (78.0%), and highest among women aged 35-44 years (93.6%) and 45-59 years (93.7%) in R5. Viral load suppression prevalence increased among all PLHIV aged 15-59 years from 52.0% in R1 to 78.3% in R5. DISCUSSION: Between 2014 and 2019, Chókwè Health and Demographic Surveillance System residents surpassed the UNAIDS targets of ≥81% of PLHIV on ART and ≥73% virally suppressed. This achievement supports the combination of efforts from household-based HIV testing and counseling, support for linkage to care and treatment, and continued investments in T&S implementation.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Prueba de VIH , Adolescente , Adulto , Recuento de Linfocito CD4 , Femenino , Encuestas de Atención de la Salud , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Mozambique/epidemiología , Vigilancia de la Población , Prevalencia , Carga Viral , Adulto Joven
12.
Clin Infect Dis ; 73(7): e2217-e2225, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32735012

RESUMEN

BACKGROUND: Children living with human immunodeficiency virus (HIV) (CLHIV) receiving antiretroviral therapy (ART) in resource-limited settings are susceptible to high rates of acquired HIV drug resistance (HIVDR), but few studies include children initiating age-appropriate World Health Organization (WHO)-recommended first-line regimens. We report data from a cohort of ART-naive South African children who initiated first-line ART. METHODS: ART-eligible CLHIV aged 0-12 years were enrolled from 2012 to 2014 at 5 public South African facilities and were followed for up to 24 months. Enrolled CLHIV received standard-of-care WHO-recommended first-line ART. At the final study visit, a dried blood spot sample was obtained for viral load and genotypic resistance testing. RESULTS: Among 72 successfully genotyped CLHIV, 49 (68.1%) received ABC/3TC/LPV/r, and 23 (31.9%) received ABC/3TC/EFV. All but 2 children on ABC/3TC/LPV/r were <3 years, and all CLHIV on ABC/3TC/EFV were ≥3 years. Overall, 80.6% (58/72) had at least one drug resistance mutation (DRM). DRMs to nonnucleoside reverse transcriptase inhibitors (NNRTIs) and nucleoside reverse transcriptase inhibitors (NRTIs) were found among 65% and 51% of all CLHIV, respectively, with no statistical difference by ART regimen. More CLHIV on ABC/3TC/EFV, 47.8% (11/23), were found to have 0 or only 1 effective antiretroviral drug remaining in their current regimen compared to 8.2% (4/49) on ABC/3TC/LPV/r. CONCLUSIONS: High levels of NNRTI and NRTI DRMs among CLHIV receiving ABC/3TC/LPV/r suggests a lasting impact of failed mother-to-child transmission interventions on DRMs. However, drug susceptibility analysis reveals that CLHIV with detectable viremia on ABC/3TC/LPV/r are more likely to have maintained at least 2 effective agents on their current HIV regimen than those on ABC/3TC/EFV.


Asunto(s)
Fármacos Anti-VIH , Farmacorresistencia Viral , Infecciones por VIH , VIH-1 , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , VIH-1/genética , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Mutación , Organización Mundial de la Salud
13.
J Int AIDS Soc ; 23(11): e25631, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33225559

RESUMEN

INTRODUCTION: The global target for 2020 is that ≥90% of people living with HIV (PLHIV) receiving antiretroviral therapy (ART) will achieve viral load suppression (VLS). We examined VLS and its determinants among adults receiving ART for at least four months. METHODS: We analysed data from the population-based HIV impact assessment (PHIA) surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe (2015 to 2017). PHIA surveys are nationally representative, cross-sectional household surveys. Data collection included structured interviews, home-based HIV testing and laboratory testing. Blood samples from PLHIV were analysed for HIV RNA, CD4 counts and recent exposure to antiretroviral drugs (ARVs). We calculated representative estimates for the prevalence of VLS (viral load <1000 copies/mL), nonsuppressed viral load (NVL; viral load ≥1000 copies/mL), virologic failure (VF; ARVs present and viral load ≥1000 copies/mL), interrupted ART (ARVs absent and viral load ≥1000 copies/mL) and rates of switching to second-line ART (protease inhibitors present) among PLHIV aged 15 to 59 years who participated in the PHIA surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe, initiated ART at least four months before the survey and were receiving ART at the time of the survey (according to self-report or ARV testing). We calculated odds ratios and incidence rate ratios for factors associated with NVL, VF, interrupted ART, and switching to second-line ART. RESULTS: We included 9200 adults receiving ART of whom 88.8% had VLS and 11.2% had NVL including 8.2% who experienced VF and 3.0% who interrupted ART. Younger age, male sex, less education, suboptimal adherence, receiving nevirapine, HIV non-disclosure, never having married and residing in Zimbabwe, Lesotho or Zambia were associated with higher odds of NVL. Among people with NVL, marriage, female sex, shorter ART duration, higher CD4 count and alcohol use were associated with lower odds for VF and higher odds for interrupted ART. Many people with VF (44.8%) had CD4 counts <200 cells/µL, but few (0.31% per year) switched to second-line ART. CONCLUSIONS: Countries are approaching global VLS targets for adults. Treatment support, in particular for younger adults, and people with higher CD4 counts, and switching of people to protease inhibitor- or integrase inhibitor-based regimens may further reduce NVL prevalence.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH/fisiología , Adolescente , Adulto , Recuento de Linfocito CD4 , Estudios Transversales , Esuatini/epidemiología , Femenino , Infecciones por VIH/epidemiología , Humanos , Incidencia , Lesotho/epidemiología , Malaui/epidemiología , Masculino , Persona de Mediana Edad , Nevirapina/uso terapéutico , Prevalencia , Encuestas y Cuestionarios , Carga Viral , Adulto Joven , Zambia/epidemiología , Zimbabwe/epidemiología
14.
J Int AIDS Soc ; 20 Suppl 72017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29171193

RESUMEN

INTRODUCTION: Logistical complexities of returning laboratory test results to participants have precluded most population-based HIV surveys conducted in sub-Saharan Africa from doing so. For HIV positive participants, this presents a missed opportunity for engagement into clinical care and improvement in health outcomes. The Population-based HIV Impact Assessment (PHIA) surveys, which measure HIV incidence and the prevalence of viral load (VL) suppression in selected African countries, are returning VL results to health facilities specified by each HIV positive participant within eight weeks of collection. We describe the performance of the specimen and data management systems used to return VL results to PHIA participants in Zimbabwe, Malawi and Zambia. METHODS: Consenting participants underwent home-based counseling and HIV rapid testing as per national testing guidelines; all confirmed HIV positive participants had VL measured at a central laboratory on either the Roche CAP/CTM or Abbott m2000 platform. On a bi-weekly basis, a dedicated data management team produced logs linking the VL test result with the participants' contact information and preferred health facility; project staff sent test results confidentially via project drivers, national courier systems, or electronically through an adapted short message service (SMS). Participants who provided cell phone numbers received SMS or phone call alerts regarding availability of VL results. RESULTS AND DISCUSSION: From 29,634 households across the three countries, 78,090 total participants 0 to 64 years in Zimbabwe and Malawi and 0 to 59 years in Zambia underwent blood draw and HIV testing. Of the 8391 total HIV positive participants identified, 8313 (99%) had VL tests performed and 8245 (99%) of these were returned to the selected health facilities. Of the 5979 VL results returned in Zimbabwe and Zambia, 85% were returned within the eight-week goal with a median turnaround time of 48 days (IQR: 33 to 61). In Malawi, where exact return dates were unavailable all 2266 returnable results reached the health facilities by 11 weeks. CONCLUSIONS: The first three PHIA surveys returned the vast majority of VL results to each HIV positive participant's preferred health facility within the eight-week target. Even in the absence of national VL monitoring systems, a system to return VL results from a population-based survey is feasible, but it requires developing laboratory and data management systems and dedicated staff. These are likely important requirements to strengthen return of results systems in routine clinical care.


Asunto(s)
Infecciones por VIH/virología , Revelación de la Verdad , Carga Viral , Adolescente , Adulto , África del Sur del Sahara , Teléfono Celular , Niño , Preescolar , Consejo , Femenino , VIH-1 , Instituciones de Salud , Humanos , Lactante , Recién Nacido , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Relaciones Médico-Paciente , Encuestas y Cuestionarios , Envío de Mensajes de Texto , Adulto Joven
15.
J Infect Dis ; 216(suppl_4): S566-S574, 2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-28934455

RESUMEN

Background: Neuraminidase (NA) inhibitors are the recommended antiviral medications for influenza treatment. However, their therapeutic efficacy can be compromised by NA changes that emerge naturally and/or following antiviral treatment. Knowledge of which molecular changes confer drug resistance of influenza A(H7N9) viruses (group 2NA) remains sparse. Methods: Fourteen amino acid substitutions were introduced into the NA of A/Shanghai/2/2013(H7N9). Recombinant N9 (recN9) proteins were expressed in a baculovirus system in insect cells and tested using the Centers for Disease Control and Prevention standardized NA inhibition (NI) assay with oseltamivir, zanamivir, peramivir, and laninamivir. The wild-type N9 crystal structure was determined in complex with oseltamivir, zanamivir, or sialic acid, and structural analysis was performed. Results: All substitutions conferred either reduced or highly reduced inhibition by at least 1 NA inhibitor; half of them caused reduced inhibition or highly reduced inhibition by all NA inhibitors. R292K conferred the highest increase in oseltamivir half-maximal inhibitory concentration (IC50), and E119D conferred the highest zanamivir IC50. Unlike N2 (another group 2NA), H274Y conferred highly reduced inhibition by oseltamivir. Additionally, R152K, a naturally occurring variation at the NA catalytic residue of A(H7N9) viruses, conferred reduced inhibition by laninamivir. Conclusions: The recNA method is a valuable tool for assessing the effect of NA changes on drug susceptibility of emerging influenza viruses.


Asunto(s)
Antivirales/farmacología , Farmacorresistencia Viral Múltiple/genética , Subtipo H7N9 del Virus de la Influenza A/efectos de los fármacos , Neuraminidasa/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Ácidos Carbocíclicos , Ciclopentanos/farmacología , Bases de Datos Genéticas , Inhibidores Enzimáticos/farmacología , Guanidinas/farmacología , Humanos , Subtipo H7N9 del Virus de la Influenza A/genética , Gripe Humana/tratamiento farmacológico , Concentración 50 Inhibidora , Neuraminidasa/genética , Oseltamivir/farmacología , Conformación Proteica , Piranos , Proteínas Recombinantes/genética , Ácidos Siálicos , Proteínas Virales/genética , Zanamivir/análogos & derivados , Zanamivir/farmacología
16.
MMWR Morb Mortal Wkly Rep ; 65(47): 1332-1335, 2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27906910

RESUMEN

The World Health Organization (WHO) recommends viral load testing as the preferred method for monitoring the clinical response of patients with human immunodeficiency virus (HIV) infection to antiretroviral therapy (ART) (1). Viral load monitoring of patients on ART helps ensure early diagnosis and confirmation of ART failure and enables clinicians to take an appropriate course of action for patient management. When viral suppression is achieved and maintained, HIV transmission is substantially decreased, as is HIV-associated morbidity and mortality (2). CDC and other U.S. government agencies and international partners are supporting multiple countries in sub-Saharan Africa to provide viral load testing of persons with HIV who are on ART. This report examines current capacity for viral load testing based on equipment provided by manufacturers and progress with viral load monitoring of patients on ART in seven sub-Saharan countries (Côte d'Ivoire, Kenya, Malawi, Namibia, South Africa, Tanzania, and Uganda) during January 2015-June 2016. By June 2016, based on the target numbers for viral load testing set by each country, adequate equipment capacity existed in all but one country. During 2015, two countries tested >85% of patients on ART (Namibia [91%] and South Africa [87%]); four countries tested <25% of patients on ART. In 2015, viral suppression was >80% among those patients who received a viral load test in all countries except Côte d'Ivoire. Sustained country commitment and a coordinated global effort is needed to reach the goal for viral load monitoring of all persons with HIV on ART.


Asunto(s)
Infecciones por VIH/virología , Vigilancia de la Población , Carga Viral , África del Sur del Sahara/epidemiología , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos
17.
MMWR Morb Mortal Wkly Rep ; 65(46): 1285-1290, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27880749

RESUMEN

Pediatric human immunodeficiency virus (HIV) infection remains an important public health issue in resource-limited settings. In 2015, 1.4 million children aged <15 years were estimated to be living with HIV (including 170,000 infants born in 2015), with the vast majority living in sub-Saharan Africa (1). In 2014, 150,000 children died from HIV-related causes worldwide (2). Access to timely HIV diagnosis and treatment for HIV-infected infants reduces HIV-associated mortality, which is approximately 50% by age 2 years without treatment (3). Since 2011, the annual number of HIV-infected children has declined by 50%. Despite this gain, in 2014, only 42% of HIV-exposed infants received a diagnostic test for HIV (2), and in 2015, only 51% of children living with HIV received antiretroviral therapy (1). Access to services for early infant diagnosis of HIV (which includes access to testing for HIV-exposed infants and clinical diagnosis of HIV-infected infants) is critical for reducing HIV-associated mortality in children aged <15 years. Using data collected from seven countries supported by the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), progress in the provision of HIV testing services for early infant diagnosis was assessed. During 2011-2015, the total number of HIV diagnostic tests performed among HIV-exposed infants within 6 weeks after birth (tests for early infant diagnosis of HIV), as recommended by the World Health Organization (WHO) increased in all seven countries (Cote d'Ivoire, the Democratic Republic of the Congo, Haiti, Malawi, South Africa, Uganda, and Zambia); however, in 2015, the rate of testing for early infant diagnosis among HIV-exposed infants was <50% in five countries. HIV positivity among those tested declined in all seven countries, with three countries (Cote d'Ivoire, the Democratic Republic of the Congo, and Uganda) reporting >50% decline. The most common challenges for access to testing for early infant diagnosis included difficulties in specimen transport, long turnaround time between specimen collection and receipt of results, and limitations in supply chain management. Further reductions in HIV mortality in children can be achieved through continued expansion and improvement of services for early infant diagnosis in PEPFAR-supported countries, including initiatives targeted to reach HIV-exposed infants, ensure access to programs for early infant diagnosis of HIV, and facilitate prompt linkage to treatment for children diagnosed with HIV infection.


Asunto(s)
Diagnóstico Precoz , Infecciones por VIH/diagnóstico , Tamizaje Masivo/estadística & datos numéricos , África del Sur del Sahara , Región del Caribe , Femenino , Infecciones por VIH/transmisión , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Embarazo
18.
J Virol ; 89(23): 11845-57, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26378167

RESUMEN

UNLABELLED: Paramyxoviruses include many important animal and human pathogens. The genome of parainfluenza virus 5 (PIV5), a prototypical paramyxovirus, encodes a V protein that inhibits viral RNA synthesis. In this work, the mechanism of inhibition was investigated. Using mutational analysis and a minigenome system, we identified regions in the N and C termini of the V protein that inhibit viral RNA synthesis: one at the very N terminus of V and the second at the C terminus of V. Furthermore, we determined that residues L16 and I17 are critical for the inhibitory function of the N-terminal region of the V protein. Both regions interact with the nucleocapsid protein (NP), an essential component of the viral RNA genome complex (RNP). Mutations at L16 and I17 abolished the interaction between NP and the N-terminal domain of V. This suggests that the interaction between NP and the N-terminal domain plays a critical role in V inhibition of viral RNA synthesis by the N-terminal domain. Both the N- and C-terminal regions inhibited viral RNA replication. The C terminus inhibited viral RNA transcription, while the N-terminal domain enhanced viral RNA transcription, suggesting that the two domains affect viral RNA through different mechanisms. Interestingly, V also inhibited the synthesis of the RNA of other paramyxoviruses, such as Nipah virus (NiV), human parainfluenza virus 3 (HPIV3), measles virus (MeV), mumps virus (MuV), and respiratory syncytial virus (RSV). This suggests that a common host factor may be involved in the replication of these paramyxoviruses. IMPORTANCE: We identified two regions of the V protein that interact with NP and determined that one of these regions enhances viral RNA transcription via its interaction with NP. Our data suggest that a common host factor may be involved in the regulation of paramyxovirus replication and could be a target for broad antiviral drug development. Understanding the regulation of paramyxovirus replication will enable the rational design of vaccines and potential antiviral drugs.


Asunto(s)
Virus de la Parainfluenza 5/genética , ARN Viral/biosíntesis , Proteínas Virales/metabolismo , Western Blotting , Cartilla de ADN/genética , Células HEK293 , Humanos , Inmunoprecipitación , Microscopía Confocal , Proteínas de la Nucleocápside/metabolismo , Virus de la Parainfluenza 5/fisiología , ARN Viral/antagonistas & inhibidores , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
PLoS One ; 10(8): e0133867, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26244768

RESUMEN

Highly pathogenic avian influenza (HPAI) H5N1 is endemic in Vietnamese poultry and has caused sporadic human infection in Vietnam since 2003. Human infections with HPAI H5N1 are of concern due to a high mortality rate and the potential for the emergence of pandemic viruses with sustained human-to-human transmission. Viruses isolated from humans in southern Vietnam have been classified as clade 1 with a single genome constellation (VN3) since their earliest detection in 2003. This is consistent with detection of this clade/genotype in poultry viruses endemic to the Mekong River Delta and surrounding regions. Comparison of H5N1 viruses detected in humans from southern Vietnamese provinces during 2012 and 2013 revealed the emergence of a 2013 reassortant virus with clade 1.1.2 hemagglutinin (HA) and neuraminidase (NA) surface protein genes but internal genes derived from clade 2.3.2.1a viruses (A/Hubei/1/2010-like; VN12). Closer analysis revealed mutations in multiple genes of this novel genotype (referred to as VN49) previously associated with increased virulence in animal models and other markers of adaptation to mammalian hosts. Despite the changes identified between the 2012 and 2013 genotypes analyzed, their virulence in a ferret model was similar. Antigenically, the 2013 viruses were less cross-reactive with ferret antiserum produced to the clade 1 progenitor virus, A/Vietnam/1203/2004, but reacted with antiserum produced against a new clade 1.1.2 WHO candidate vaccine virus (A/Cambodia/W0526301/2012) with comparable hemagglutination inhibition titers as the homologous antigen. Together, these results indicate changes to both surface and internal protein genes of H5N1 viruses circulating in southern Vietnam compared to 2012 and earlier viruses.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A/fisiología , Gripe Aviar/virología , Gripe Humana/virología , Pandemias , Secuencia de Aminoácidos , Animales , Genoma Viral/genética , Genotipo , Hemaglutininas Virales/clasificación , Hemaglutininas Virales/genética , Humanos , Subtipo H5N1 del Virus de la Influenza A/clasificación , Subtipo H5N1 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Neuraminidasa/clasificación , Neuraminidasa/genética , Filogenia , Aves de Corral/virología , Recombinación Genética , Vietnam/epidemiología , Proteínas Virales/genética
20.
J Infect Dis ; 211(2): 249-57, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25124927

RESUMEN

BACKGROUND: Patients contracting influenza A(H7N9) infection often developed severe disease causing respiratory failure. Neuraminidase (NA) inhibitors (NAIs) are the primary option for treatment, but information on drug-resistance markers for influenza A(H7N9) is limited. METHODS: Four NA variants of A/Taiwan/1/2013(H7N9) virus containing a single substitution (NA-E119V, NA-I222K, NA-I222R, or NA-R292K) recovered from an oseltamivir-treated patient were tested for NAI susceptibility in vitro; their replicative fitness was evaluated in cell culture, mice, and ferrets. RESULTS: NA-R292K led to highly reduced inhibition by oseltamivir and peramivir, while NA-E119V, NA-I222K, and NA-I222R caused reduced inhibition by oseltamivir. Mice infected with any virus showed severe clinical signs with high mortality rates. NA-I222K virus was the most virulent in mice, whereas virus lacking NA change (NA-WT) and NA-R292K virus seemed the least virulent. Sequence analysis suggests that PB2-S714N increased virulence of NA-I222K virus in mice; NS1-K126R, alone or in combination with PB2-V227M, produced contrasting effects in NA-WT and NA-R292K viruses. In ferrets, all viruses replicated to high titers in the upper respiratory tract but produced only mild illness. NA-R292K virus, showed reduced replicative fitness in this animal model. CONCLUSIONS: Our data highlight challenges in assessment of the replicative fitness of H7N9 NA variants that emerged in NAI-treated patients.


Asunto(s)
Antivirales/uso terapéutico , Farmacorresistencia Viral , Subtipo H7N9 del Virus de la Influenza A/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Gripe Humana/virología , Oseltamivir/uso terapéutico , Animales , Modelos Animales de Enfermedad , Hurones , Humanos , Subtipo H7N9 del Virus de la Influenza A/enzimología , Subtipo H7N9 del Virus de la Influenza A/genética , Subtipo H7N9 del Virus de la Influenza A/aislamiento & purificación , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Proteínas Mutantes/genética , Mutación Missense , Neuraminidasa/genética , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Proteínas Virales/genética , Cultivo de Virus , Replicación Viral
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