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1.
Int J Infect Dis ; 112: 281-287, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34536612

RESUMEN

INTRODUCTION: Serological testing is needed to better understand the epidemiology of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Rapid diagnostic tests (RDTs) have been developed to detect specific antibodies, IgM and IgG, to the virus. The performance of 25 of these RDTs was evaluated. METHODS: A serological reference panel of 50 positive and 100 negative plasma specimens was developed from SARS-CoV-2 PCR and antibody positive patients and pre-pandemic SARS-CoV-2-negative specimens collected in 2016. Test performance of the 25 RDTs was evaluated against this panel. RESULTS: A total of 10 RDTs had a sensitivity ≥98%, while 13 RDTs had a specificity ≥98% to anti-SARS-CoV-2 IgG antibodies. Four RDTs (Boson, MultiG, Standard Q, and VivaDiag) had both sensitivity and specificity ≥98% to anti-SARS-CoV-2 IgG antibodies. Only three RDTs had a sensitivity ≥98%, while 10 RDTs had a specificity ≥98% to anti-SARS-CoV-2 IgM antibodies. Three RDTs (Autobio, MultiG, and Standard Q) had sensitivity and specificity ≥98% to combined IgG/IgM. The RDTs that performed well also had perfect or almost perfect inter-reader agreement. CONCLUSIONS: This evaluation identified three RDTs with a sensitivity and specificity to IgM/IgG antibodies of ≥98% with the potential for widespread antibody testing in Uganda.


Asunto(s)
COVID-19 , SARS-CoV-2 , Academias e Institutos , Anticuerpos Antivirales , Pruebas Diagnósticas de Rutina , Humanos , Inmunoglobulina M , Sensibilidad y Especificidad , Uganda/epidemiología
2.
J Antimicrob Chemother ; 76(9): 2407-2414, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-33993252

RESUMEN

BACKGROUND: WHO revised their HIV drug resistance (HIVDR) monitoring strategy in 2014, enabling countries to generate nationally representative HIVDR prevalence estimates from surveys conducted using this methodology. In 2016, we adopted this strategy in Uganda and conducted an HIVDR survey among adults initiating or reinitiating ART. METHODS: A cross-sectional survey of adults aged ≥18 years initiating or reinitiating ART was conducted at 23 sites using a two-stage cluster design sampling method. Participants provided written informed consent prior to enrolment. Whole blood collected in EDTA vacutainer tubes was used for preparation of dried blood spot (DBS) specimens or plasma. Samples were shipped from the sites to the Central Public Health Laboratory (CPHL) for temporary storage before transfer to the Uganda Virus Research Institute (UVRI) for genotyping. Prevalence of HIVDR among adults initiating or reinitiating ART was determined. RESULTS: Specimens from 491 participants (median age 32 years and 61.5% female) were collected between August and December 2016. Specimens from 351 participants were successfully genotyped. Forty-nine had drug resistance mutations, yielding an overall weighted HIVDR prevalence of 18.2% with the highest noted for NNRTIs at 14.1%. CONCLUSIONS: We observed a high HIVDR prevalence for NNRTIs among adults prior to initiating or reinitiating ART in Uganda. This is above WHO's recommended threshold of 10% when countries should consider changing from NNRTI- to dolutegravir-based first-line regimens. This recommendation was adopted in the revised Ugandan ART guidelines. Dolutegravir-containing ART regimens are preferred for first- and second-line ART regimens.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Adolescente , Adulto , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Estudios Transversales , Farmacorresistencia Viral , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Uganda/epidemiología , Carga Viral
3.
AIDS Res Hum Retroviruses ; 37(12): 893-896, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33499732

RESUMEN

Point of care rapid recency testing for HIV-1 may be a cost-effective tool to identify recently infected individuals for incidence estimation, and focused HIV prevention through intensified contact tracing. We validated the Asante™ HIV-1 rapid recency® assay for use in Uganda. Archived specimens (serum/plasma), collected from longitudinally observed HIV-1 recently and long-term infected participants, were tested with the Asante HIV-1 rapid recency assay per manufacturer's instructions. Previously identified antiretroviral therapy (ART)-naive samples with known seroconversions within 6 months of follow-up were tested in independent laboratories: the Rakai Health Sciences Program (RHSP) and the Uganda Virus Research Institute HIV Reference Laboratory (UVRI-HRL). In addition, samples from participants who seroconverted within 6-18 months and samples from individuals with chronic HIV-1 infection of at least 18 months duration were classified into three categories: ART naive, ART exposed with suppressed viral loads, and ART exposed with detectable viremia. Of the 85 samples seroconverting in ≤6 months, 27 and 42 samples were identified as "recent" by the Asante HIV-1 rapid recency test at the RHSP laboratory and UVRI-HRL, corresponding to sensitivities of 32% and 49%, respectively. There was 72% agreement between the laboratories (Cohen's kappa = 0.481, 95% CI = 0.317-0.646, p < .0001). Specificity was 100% (200/200) among chronically infected ART-naive samples. The Asante HIV-1 rapid recency assay had low sensitivity for detection of recent HIV-1 infections in Uganda, with substantial interlaboratory variability due to differential interpretation of the test strip bands. Specificity was excellent. Assessment of assay performance in other settings is needed to guide decisions on test utility.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Humanos , Uganda/epidemiología , Carga Viral
4.
Int J Infect Dis ; 104: 282-286, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33130198

RESUMEN

OBJECTIVES: There is a high demand for SARS-CoV-2 testing to identify COVID-19 cases. Real-time quantitative PCR (qRT-PCR) is the recommended diagnostic test but a number of constraints prevent its widespread implementation, including cost. The aim of this study was to evaluate a low cost and easy to use rapid antigen test for diagnosing COVID-19 at the point of care. METHODS: Nasopharyngeal swabs from suspected COVID-19 cases and low-risk volunteers were tested with the STANDARD Q COVID-19 Ag Test and the results were compared with the qRT-PCR results. RESULTS: In total, 262 samples were collected, including 90 qRT-PCR positives. The majority of samples were from males (89%) with a mean age of 34 years and only 13 (14%) of the positives were mildly symptomatic. The sensitivity and specificity of the antigen test were 70.0% (95% confidence interval (CI): 60-79) and 92% (95% CI: 87-96), respectively, and the diagnostic accuracy was 84% (95% CI: 79-88). The antigen test was more likely to be positive for samples with qRT-PCR Ct values ≤29, with a sensitivity of 92%. CONCLUSIONS: The STANDARD Q COVID-19 Ag Test performed less than optimally in this evaluation. However, the test may still have an important role to play early in infection when timely access to molecular testing is not available but the results should be confirmed by qRT-PCR.


Asunto(s)
Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/inmunología , Adulto , COVID-19/virología , Femenino , Humanos , Masculino , Nasofaringe/virología , Sistemas de Atención de Punto , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Sensibilidad y Especificidad , Uganda
5.
PLoS One ; 15(4): e0230451, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32287264

RESUMEN

INTRODUCTION: With the scale-up of antiretroviral therapy (ART) there is a need to monitor programme performance to maximize ART efficacy and to prevent emergence of HIV drug resistance (HIVDR). In keeping with the elements of the World Health Organisation (WHO) guidance we carried out a nationally representative assessment of early warning indicators (EWI) at 304 randomly selected ART service outlets in Uganda. METHODS: Retrospective patient data was extracted for the six EWIs for HIVDR including; on-time antiretroviral (ARV) drug pick-up, patient retention on ART at 12 months, ART dispensing practices, ARV drug stock-outs, viral load suppression (VLS) and viral load (VL) testing completion. Point prevalence for each clinic and national aggregate prevalence with 95% confidence intervals (CI) for all clinics were estimated and facility performances were computed and association between EWIs and programmatic factors assessed using Fisher's Exact Test. RESULTS: Facilities meeting the EWI targets: on-time pill pick-up was 9.5%, more facilities in the north met this target (p = 0.040). Retention on ART at 12 months was 24.1%, facilities in Kampala region (p<0.001) and Specialized ART clinics (p = 0.01) performed better in this indicator. Pharmacy stock-outs was 33.6%, with more facilities in Kampala (p<0.001), specialized ART clinics (p<0.001) and private-for-profit (p<0.001) meeting this target. Dispensing practices was met by 100% of the facilities. VLS was met by 49.2% and 50.8% of facilities met VL completion target with facilities in central region performing better (p<0.001). National prevalence for the EWIs was: on-time pill pick-up 63.3% (CI: 58.9-67.8); retention on ART at 12 months 69.9% (CI: 63.8-76.0); dispensing practices 100.0%; VLS 85.2% (CI: 81.8-88.5) and VL completion, 60.7% (CI: 56.9-64.6). CONCLUSION: Dispensing practices in all facilities were in line with the national guidelines however, there still remains a challenge to long-term ART programmatic success in monitoring patient response to treatment, and maintaining patients on ART without interruptions arising due to poor patient adherence and as a consequence of ARV supply interruption. It is therefore of high importance that the national ART program ensures intensified follow-up for patients, ensuring uninterrupted supply of ARV drugs and increasing VL monitoring at treatment centres, in order to improve patient outcomes and avert preventable HIVDR.


Asunto(s)
Antirretrovirales/provisión & distribución , Infecciones por VIH/tratamiento farmacológico , Cooperación del Paciente/estadística & datos numéricos , Adulto , Antirretrovirales/uso terapéutico , Farmacorresistencia Viral , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Prevalencia , Estudios Retrospectivos , Encuestas y Cuestionarios , Uganda , Carga Viral , Organización Mundial de la Salud
6.
J Antimicrob Chemother ; 75(5): 1280-1289, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32025714

RESUMEN

OBJECTIVES: We implemented the WHO cross-sectional survey protocol to determine rates of HIV viral load (VL) suppression (VLS), and weighted prevalence, predictors and patterns of acquired drug resistance (ADR) in individuals with virological failure (VF) defined as VL ≥1000 copies/mL. METHODS: We enrolled 547 and 1064 adult participants on first-line ART for 12 (±3) months (ADR12) and ≥48 months (ADR48), respectively. Dried blood spots and plasma specimens were collected for VL testing and genotyping among the VFs. RESULTS: VLS was 95.0% (95% CI 93.4%-96.5%) in the ADR12 group and 87.9% (95% CI 85.0%-90.9%) in the ADR48 group. The weighted prevalence of ADR was 96.1% (95% CI 72.9%-99.6%) in the ADR12 and 90.4% (95% CI 73.6-96.8%) in the ADR48 group, out of the 30 and 95 successful genotypes in the respective groups. Initiation on a zidovudine-based regimen compared with a tenofovir-based regimen was significantly associated with VF in the ADR48 group; adjusted OR (AOR) 1.96 (95% CI 1.13-3.39). Independent predictors of ADR in the ADR48 group were initiation on a zidovudine-based regimen compared with tenofovir-based regimens, AOR 3.16 (95% CI 1.34-7.46) and ART duration of ≥82 months compared with <82 months, AOR 1.92 (95% CI 1.03-3.59). CONCLUSIONS: While good VLS was observed, the high prevalence of ADR among the VFs before they underwent the recommended three intensive adherence counselling (IAC) sessions followed by repeat VL testing implies that IAC prior to treatment switching may be of limited benefit in improving VLS.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Estudios Transversales , Resistencia a Medicamentos , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Prevalencia , Insuficiencia del Tratamiento , Uganda/epidemiología , Carga Viral
7.
BMC Infect Dis ; 18(1): 93, 2018 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-29482500

RESUMEN

INTRODUCTION: The World Health Organization recommends that countries conduct two phase evaluations of HIV rapid tests (RTs) in order to come up with the best algorithms. In this report, we present the first ever such evaluation in Uganda, involving both blood and oral based RTs. The role of weak positive (WP) bands on the accuracy of the individual RT and on the algorithms was also investigated. METHODS: In total 11 blood based and 3 oral transudate kits were evaluated. All together 2746 participants from seven sites, covering the four different regions of Uganda participated. Two enzyme immunoassays (EIAs) run in parallel were used as the gold standard. The performance and cost of the different algorithms was calculated, with a pre-determined price cut-off of either cheaper or within 20% price of the current algorithm of Determine + Statpak + Unigold. In the second phase, the three best algorithms selected in phase I were used at the point of care for purposes of quality control using finger stick whole blood. RESULTS: We identified three algorithms; Determine + SD Bioline + Statpak; Determine + Statpak + SD Bioline, both with the same sensitivity and specificity of 99.2% and 99.1% respectively and Determine + Statpak + Insti, with sensitivity and specificity of 99.1% and 99% respectively as having performed better and met the cost requirements. There were 15 other algorithms that performed better than the current one but rated more than the 20% price. None of the 3 oral mucosal transudate kits were suitable for inclusion in an algorithm because of their low sensitivities. Band intensity affected the performance of individual RTs but not the final algorithms. CONCLUSION: We have come up with three algorithms we recommend for public or Government procurement based on accuracy and cost. In case one algorithm is preferred, we recommend to replace Unigold, the current tie breaker with SD Bioline. We further recommend that all the 18 algorithms that have shown better performance than the current one are made available to the private sector where cost may not be a limiting factor.


Asunto(s)
Infecciones por VIH/diagnóstico , VIH-1/aislamiento & purificación , Tamizaje Masivo/métodos , Juego de Reactivos para Diagnóstico , Adulto , Algoritmos , Femenino , Infecciones por VIH/virología , Humanos , Técnicas para Inmunoenzimas/métodos , Técnicas para Inmunoenzimas/normas , Masculino , Tamizaje Masivo/normas , Sistemas de Atención de Punto , Valor Predictivo de las Pruebas , Juego de Reactivos para Diagnóstico/normas , Sensibilidad y Especificidad , Uganda
8.
Lancet Infect Dis ; 18(3): 346-355, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29198909

RESUMEN

BACKGROUND: Pretreatment drug resistance in people initiating or re-initiating antiretroviral therapy (ART) containing non-nucleoside reverse transcriptase inhibitors (NNRTIs) might compromise HIV control in low-income and middle-income countries (LMICs). We aimed to assess the scale of this problem and whether it is associated with the intiation or re-initiation of ART in people who have had previous exposure to antiretroviral drugs. METHODS: This study was a systematic review and meta-regression analysis. We assessed regional prevalence of pretreatment drug resistance and risk of pretreatment drug resistance in people initiating ART who reported previous ART exposure. We systematically screened publications and unpublished datasets for pretreatment drug-resistance data in individuals in LMICs initiating or re-initiating first-line ART from LMICs. We searched for studies in PubMed and Embase and conference abstracts and presentations from the Conference on Retroviruses and Opportunistic Infections, the International AIDS Society Conference, and the International Drug Resistance Workshop for the period Jan 1, 2001, to Dec 31, 2016. To assess the prevalence of drug resistance within a specified region at any specific timepoint, we extracted study level data and pooled prevalence estimates within the region using an empty logistic regression model with a random effect at the study level. We used random effects meta-regression to relate sampling year to prevalence of pretreatment drug resistance within geographical regions. FINDINGS: We identified 358 datasets that contributed data to our analyses, representing 56 044 adults in 63 countries. Prevalence estimates of pretreatment NNRTI resistance in 2016 were 11·0% (7·5-15·9) in southern Africa, 10·1% (5·1-19·4) in eastern Africa, 7·2% (2·9-16·5) in western and central Africa, and 9·4% (6·6-13·2) in Latin America and the Caribbean. There were substantial increases in pretreatment NNRTI resistance per year in all regions. The yearly increases in the odds of pretreatment drug resistance were 23% (95% CI 16-29) in southern Africa, 17% (5-30) in eastern Africa, 17% (6-29) in western and central Africa, 11% (5-18) in Latin America and the Caribbean, and 11% (2-20) in Asia. Estimated increases in the absolute prevalence of pretreatment drug resistance between 2015 and 2016 ranged from 0·3% in Asia to 1·8% in southern Africa. INTERPRETATION: Pretreatment drug resistance is increasing at substantial rate in LMICs, especially in sub-Saharan Africa. In 2016, the prevalence of pretreatment NNRTI resistance was near WHO's 10% threshold for changing first-line ART in southern and eastern Africa and Latin America, underscoring the need for routine national HIV drug-resistance surveillance and review of national policies for first-line ART regimen composition. FUNDING: Bill & Melinda Gates Foundation and World Health Organization.


Asunto(s)
Fármacos Anti-VIH/farmacología , Países en Desarrollo , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Infecciones por VIH/epidemiología , Humanos
9.
Clin Infect Dis ; 65(12): 2018-2025, 2017 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-29020335

RESUMEN

BACKGROUND: Programs for the prevention of mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV) have been scaled up in many low- and middle-income countries. However, HIV drug resistance (HIVDR) data among HIV-1-infected young children remain limited. METHODS: Surveys of pretreatment HIVDR among children aged <18 months who were diagnosed with HIV through early infant diagnosis were conducted in 5 sub-Saharan African countries (Mozambique, Swaziland, South Africa, Uganda, and Zimbabwe) between 2011 and 2014 following World Health Organization (WHO) guidance. Deidentified demographic and clinical data were used to explore risk factors associated with nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance. RESULTS: Among the 1450 genotypes analyzed, 1048 had accompanying demographic and clinical data. The median age of children was 4 months; 50.4% were female. HIV from 54.1% showed resistance to 1 or more antiretroviral (ARV) drugs, with 53.0% and 8.8% having resistance to 1 or more NNRTI or nucleoside reverse transcriptase inhibitors, respectively. NNRTI resistance was particularly high in children exposed to ARV drugs through PMTCT; adjusted odds ratios were 1.8 (95% confidence interval [CI], 1.3-2.6) for maternal exposure only and 2.4 (CI, 1.6-3.6) for neonatal exposure only. CONCLUSIONS: Protease inhibitor-based regimens in children aged <3 years are currently recommended by WHO, but the implementation of this recommendation is suboptimal. These results reinforce the urgent need to overcome barriers to scaling up pediatric protease inhibitor-based regimens in sub-Saharan Africa and underscore the need to accelerate the study and approval of integrase inhibitors for use in young children.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , VIH-1/efectos de los fármacos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , África del Sur del Sahara/epidemiología , Fármacos Anti-VIH/uso terapéutico , Femenino , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/genética , Humanos , Lactante , Recién Nacido , Masculino , Mozambique/epidemiología , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Factores de Riesgo , Encuestas y Cuestionarios , Uganda/epidemiología , Carga Viral
10.
AIDS Res Hum Retroviruses ; 32(3): 237-46, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26548707

RESUMEN

Control of HIV replication through CD4(+) and CD8(+) T cells might be possible, but the functional and phenotypic characteristics of such cells are not defined. Among cytokines produced by T cells, CCR5 ligands, including macrophage inflammatory protein-1 beta (MIP-1ß), compete for the CCR5 coreceptor with HIV, promoting CCR5 internalization and decreasing its availability for virus binding. Interferon (IFN)-γ also has some antiviral activity and has been used as a read-out for T cell immunogenicity. We used cultured ELISpot assays to compare the relative contribution of MIP-1ß and IFN-γ to HIV-specific responses. The magnitude of responses was 1.36 times higher for MIP-1ß compared to IFN-γ. The breadth of the MIP-1ß response (45.41%) was significantly higher than IFN-γ (36.88%), with considerable overlap between the peptide pools that stimulated both MIP-1ß and IFN-γ production. Subtype A and D cross-reactive responses were observed both at stimulation and test level, but MIP-1ß and IFN-γ responses displayed different effect patterns. We conclude that the MIP-1ß ELISpot would be a useful complement to the evaluation of the immunogenicity of HIV vaccines and the activity of adjuvants.


Asunto(s)
Quimiocina CCL4/metabolismo , Infecciones por VIH/inmunología , VIH-1/inmunología , Interferón gamma/metabolismo , Leucocitos Mononucleares/inmunología , Adolescente , Adulto , Células Cultivadas , Ensayo de Immunospot Ligado a Enzimas , Femenino , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Uganda
11.
PLoS One ; 10(12): e0145536, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26700639

RESUMEN

BACKGROUND: With the scale-up of antiretroviral therapy (ART), monitoring programme performance is needed to maximize ART efficacy and limit HIV drug resistance (HIVDR). METHODS: We implemented a WHO HIVDR prospective survey protocol at three treatment centers between 2012 and 2013. Data were abstracted from patient records at ART start (T1) and after 12 months (T2). Genotyping was performed in the HIV pol region at the two time points. RESULTS: Of the 425 patients enrolled, at T2, 20 (4.7%) had died, 66 (15.5%) were lost to follow-up, 313 (73.6%) were still on first-line, 8 (1.9%) had switched to second-line, 17 (4.0%) had transferred out and 1 (0.2%) had stopped treatment. At T2, 272 out of 321 on first and second line (84.7%) suppressed below 1000 copies/ml and the HIV DR prevention rate was 70.1%, just within the WHO threshold of ≥ 70%. The proportion of participants with potential HIVDR was 20.9%, which is higher than the 18.8% based on pooled analyses from African studies. Of the 35 patients with mutations at T2, 80% had M184V/I, 65.7% Y181C, and 48.6% (54.8% excluding those not on Tenofovir) had K65R mutations. 22.9% had Thymidine Analogue Mutations (TAMs). Factors significantly associated with HIVDR prevention at T2 were: baseline viral load (VL) <100,000 copies/ml [Adjusted odds ratio (AOR) 3.13, 95% confidence interval (CI): 1.36-7.19] and facility. Independent baseline predictors for HIVDR mutations at T2 were: CD4 count < 250 cells/µl (AOR 2.80, 95% CI: 1.08-7.29) and viral load ≥ 100,000 copies/ml (AOR 2.48, 95% CI: 1.00-6.14). CONCLUSION: Strengthening defaulter tracing, intensified follow-up for patients with low CD4 counts and/or high VL at ART initiation together with early treatment initiation above 250 CD4 cells/ul and adequate patient counselling would improve ART efficacy and HIVDR prevention. The high rate of K65R and TAMs could compromise second line regimens including NRTIs.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Farmacorresistencia Viral , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Adulto , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Uganda/epidemiología , Carga Viral
12.
J Virol ; 87(16): 9053-63, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23760253

RESUMEN

HIV-exposed and yet persistently uninfected individuals have been an intriguing, repeated observation in multiple studies, but uncertainty persists on the significance and implications of this in devising protective strategies against HIV. We carried out a cross-sectional analysis of exposed uninfected partners in a Ugandan cohort of heterosexual serodiscordant couples (37.5% antiretroviral therapy naive) comparing their T cell responses to HIV peptides with those of unexposed uninfected individuals. We used an objective definition of exposure and inclusion criteria, blinded ex vivo and cultured gamma interferon (IFN-γ) enzyme-linked immunospot assays, and multiparameter flow cytometry and intracellular cytokine staining to investigate the features of the HIV-specific response in exposed versus unexposed uninfected individuals. A response rate to HIV was detectable in unexposed uninfected (5.7%, 95% confidence interval [CI] = 3.3 to 8.1%) and, at a significantly higher level (12.5%, 95% CI = 9.7 to 15.4%, P = 0.0004), in exposed uninfected individuals. The response rate to Gag was significantly higher in exposed uninfected (10/50 [20.%]) compared to unexposed uninfected (1/35 [2.9%]) individuals (P = 0.0004). The magnitude of responses was also greater in exposed uninfected individuals but not statistically significant. The average number of peptide pools recognized was significantly higher in exposed uninfected subjects than in unexposed uninfected subjects (1.21 versus 0.47; P = 0.0106). The proportion of multifunctional responses was different in the two groups, with a higher proportion of single cytokine responses, mostly IFN-γ, in unexposed uninfected individuals compared to exposed uninfected individuals. Our findings demonstrate both quantitative and qualitative differences in T cell reactivity to HIV between HESN (HIV exposed seronegative) and HUSN (HIV unexposed seronegative) subject groups but do not discriminate as to whether they represent markers of exposure or of protection against HIV infection.


Asunto(s)
VIH/inmunología , Linfocitos T/inmunología , Adulto , Estudios Transversales , Citocinas/biosíntesis , Ensayo de Immunospot Ligado a Enzimas , Composición Familiar , Salud de la Familia , Femenino , Citometría de Flujo , Humanos , Masculino , Uganda
13.
PLoS One ; 7(5): e37727, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22629447

RESUMEN

BACKGROUND: The CHAVI002 study was designed to characterize immune responses, particularly HIV-specific T-cell responses, amongst 2 cohorts of HIV-exposed seronegative (HESN) individuals. The absence of a clear definition of HESNs has impaired comparison of research within and between such cohorts. This report describes two distinct HESN cohorts and attempts to quantify HIV exposure using a 'HIV risk index' (RI) model. METHODS: HIV serodiscordant couples (UK; 24, Uganda; 72) and HIV unexposed seronegative (HUSN) controls (UK; 14, Uganda; 26 couples, 3 individuals) completed sexual behavior questionnaires every 3 months over a 9 month period. The two cohorts were heterogeneous, with most HESNs in the UK men who have sex with men (MSM), while all HESNs in Uganda were in heterosexual relationships. Concordance of responses between partners was determined. Each participant's sexual behavior score (SBS) was estimated based on the number and type of unprotected sex acts carried out in defined time periods. Independent HIV acquisition risk factors (partner plasma viral load, STIs, male circumcision, pregnancy) were integrated with the SBS, generating a RI for each HESN. RESULTS: 96 HIV serodiscordant couples completed 929 SBQs. SBSs remained relatively stable amongst the UK cohort, whilst decreasing from Visit 1 to 2 in the Ugandan cohort. Compared to the Ugandan cohort, SBSs and RIs in the UK cohort were lower at visit 1, and generally higher at later visits. Differences between the cohorts, with lower rates of ART use in Uganda and higher risk per-act sex in the UK, had major impacts on the SBSs and RIs of each cohort. There was one HIV transmission event in the UK cohort. CONCLUSIONS: Employment of a risk quantification model facilitated quantification and comparison of HIV acquisition risk across two disparate HIV serodiscordant couple cohorts.


Asunto(s)
Infecciones por VIH/psicología , Seropositividad para VIH/psicología , Heterosexualidad/psicología , Homosexualidad Masculina/psicología , Asunción de Riesgos , Conducta Sexual/psicología , Parejas Sexuales/psicología , Adulto , Estudios de Cohortes , Composición Familiar , Femenino , Infecciones por VIH/transmisión , Seropositividad para VIH/transmisión , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Conducta Sexual/estadística & datos numéricos , Uganda , Reino Unido , Carga Viral
14.
AIDS ; 25(7): 905-10, 2011 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-21399479

RESUMEN

OBJECTIVE: To assess the emergence of transmitted HIV-1 drug resistance (TDR) in Kampala, Uganda, 10 years after the scale-up of antiretroviral treatment (ART) and to compare with a previous survey among antenatal clinic attendees in 2007 (reporting 0% TDR). DESIGN: A cross-sectional survey was conducted among newly HIV-1 diagnosed, antiretroviral-naive young adults attending two large voluntary counseling and testing centers within the geographic area of Kampala. METHODS: Proxy criteria for recent HIV-1 infection were used as defined by the WHO. Population sequencing of the pol gene was performed on plasma samples with HIV-1 RNA at least 1000 copies/ml. Surveillance drug resistance mutations (SDRMs) were identified according to the 2009 WHO list for surveillance of TDR. HIV-1 subtypes were designated using maximum likelihood phylogenetic reconstruction. RESULTS: : Genotypic test results were obtained for 70 of 77 (90.9%) participants. SDRMs were identified in six samples yielding a prevalence of TDR of 8.6% (95% confidence interval 3.2-17.7%). Two had SDRMs to nucleoside reverse-transcriptase inhibitors (D67G and L210W), three had SDRMs to nonnucleoside reverse transcriptase inhibitors (G190A, G190S, and K101E), and one had SDRMs to protease inhibitors (N88D). Frequencies of HIV-1 subtypes were A (36/70, 51.4%), C ( two of 70; 2.9%), D (23/70, 32.9%), and unique recombinant forms (nine of 70, 12.9%). CONCLUSION: This repeated survey suggests an increase in TDR in Kampala, compared with a previous survey. This finding justifies increased vigilance with respect to surveillance of TDR in areas in Africa where ART programs are rolled-out.


Asunto(s)
Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Estudios Transversales , Femenino , Genes pol/efectos de los fármacos , Genotipo , Infecciones por VIH/genética , Infecciones por VIH/transmisión , VIH-1/efectos de los fármacos , Humanos , Masculino , Embarazo , Prevalencia , Uganda , Adulto Joven
15.
AIDS Care ; 21(7): 903-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20024747

RESUMEN

HIV/AIDS has had a devastating impact at individual, household and community levels. This qualitative research investigates the role of HIV voluntary counselling and testing (VCT) and treatment in enabling HIV-positive Ugandans to cope with this disease. Twelve predetermined focus group discussions (FGDs) were conducted; six with men and six with women. Half of the men and women's groups were receiving antiretroviral therapy (ART) and half were not. An FGD was held with the health care providers administering ART. Testing for HIV was perceived as soliciting a death warrant. Participants affirmed that the incentive for testing was the possibility of accessing free ART. They described experiencing gender-variant stigma and depression on confirming their HIV status and commended the role of counselling in supporting them to adopt positive living. For those receiving ART, counselling reinforced treatment adherence. The findings also revealed gender differences in treatment adherence strategies. ART was described to reduce disease symptoms and restore physical health allowing them to resume their daily activities. Additionally, ART was preferred over traditional herbal treatment because it had clear dosages, expiry dates and was scientifically manufactured. Those that were not receiving ART bore myths and misconceptions about the effectiveness and side effects of ART, delaying the decision to seek treatment. Stigma and the attached concern of HIV/AIDS-related swift death, is a major barrier for VCT. Based on this study's findings, ensuring the provision of quality assured and gender conscious VCT and ART delivery services will enhance positive living and enforce compliance to ART programmes.


Asunto(s)
Infecciones por VIH/psicología , Aceptación de la Atención de Salud , Prejuicio , Adulto , Fármacos Anti-VIH/uso terapéutico , Consejo/estadística & datos numéricos , Femenino , Grupos Focales , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Medicinas Tradicionales Africanas/psicología , Persona de Mediana Edad , Investigación Cualitativa , Factores Sexuales , Uganda , Programas Voluntarios , Adulto Joven
16.
Trop Med Int Health ; 14(5): 556-63, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19320871

RESUMEN

OBJECTIVE: To evaluate the effect of highly active anti-retroviral therapy (HAART) and cotrimoxazole prophylaxis on morbidity after HAART eligibility. METHODS: Between 1999 and 2006, we collected morbidity data from a community-based cohort of HAART-eligible patients, comparing patients initiating HAART and those non-HAART. Patients aged 15 years or older visited the clinic every 6 months and when ill. Baseline data on patients' characteristics, WHO stage, haemoglobin and CD4+ T-cell counts, along with follow-up data on morbidity (new, recurrent and drug-related), were collected for the first year after initiating HAART or becoming HAART-eligible. We estimated the overall effect of HAART on morbidity; adjusted for the effect of cotrimoxazole prophylaxis by Mantel-Haenszel methods. A negative binomial regression model was used to assess rate ratios (RR) after adjustment for other confounders, including cotrimoxazole. RESULTS: A total of 219 HAART patients (median age 37 years; 73% women; 82% using cotrimoxazole prophylaxis, median haemoglobin 11.7 g/dl and median CD4+ 131 cells/microl) experienced 94 events in 127 person-years. 616 non-HAART patients (median age 33 years; 70% women; 26% using cotrimoxazole prophylaxis, median haemoglobin 11.2 g/dl and median CD4+ 130 cells/microl) experienced 862 events in 474 person-years. The overall morbidity during the first year of HAART was 80% lower than among non-HAART patients (adjusted RR = 0.20, 95% CI: 0.12-0.34). Cotrimoxazole prophylaxis also reduced morbidity (adjusted RR = 0.65, 95% CI: 0.45-0.94). CONCLUSION: These results confirm the reduction in morbidity due to HAART, and the additional protection of cotrimoxazole prophylaxis.


Asunto(s)
Antiinfecciosos/uso terapéutico , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Adulto , Anciano , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Uganda/epidemiología , Adulto Joven
17.
PLoS One ; 4(1): e4188, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19142234

RESUMEN

BACKGROUND: Some HIV infected individuals remain asymptomatic for protracted periods of time in the absence of antiretroviral therapy (ART). Virological control, CD4 T cell loss and HIV-specific responses are some of the key interrelated determinants of HIV-1 disease progression. In this study, possible interactions between viral load, CD4 T cell slopes, host genetics and HIV-specific IFN-gamma responses were evaluated in chronically HIV-1-infected adults. METHODOLOGY/PRINCIPAL FINDINGS: Multilevel regression modeling was used to stratify clade A or D HIV-infected individuals into disease progression groups based on CD4 T cell slopes. ELISpot assays were used to quantify the frequency and magnitude of HIV-induced IFN-gamma responses in 7 defined rapid progressors (RPs) and 14 defined slow progressors (SPs) at a single time point. HLA typing was performed using reference strand conformational analysis (RSCA). Although neither the breadth nor the magnitude of the proteome-wide HIV-specific IFN-gamma response correlated with viral load, slow disease progression was associated with over-representation of host immunogenetic protective HLA B* alleles (10 of 14 SPs compared to 0 of 7; p = 0.004, Fisher's Exact) especially B*57 and B*5801, multiclade Gag T-cell targeting (71%, 10 of 14 SPs compared to 14%, 1 of 7 RPs); p = 0.029, Fisher's Exact test and evident virological control (3.65 compared to 5.46 log10 copies/mL in SPs and RPs respectively); p<0.001, unpaired student's t-test CONCLUSIONS: These data are consistent with others that associated protection from HIV disease with inherent host HLA B allele-mediated ability to induce broader Gag T-cell targeting coupled with apparent virological control. These immunogenetic features of Gag-specific immune response which could influence disease progression may provide useful insight in future HIV vaccine design.


Asunto(s)
Infecciones por VIH/patología , Antígenos HLA-B/genética , Linfocitos T/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Alelos , Linfocitos T CD4-Positivos , Progresión de la Enfermedad , Infecciones por VIH/inmunología , Humanos , Interferón gamma/inmunología , Uganda , Carga Viral
18.
AIDS ; 22 Suppl 1: S123-30, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18664944

RESUMEN

OBJECTIVE: To assess the psychometric performance of using standard gamble (SG), time trade-off (TTO) and visual analogue scale (VAS) in the evaluation of three predetermined HIV/AIDS health states in HIV-infected Ugandans, for use in cost-effectiveness analyses. METHODS: We recruited participants with CD4 cells <200/microl from the Development of AntiRetroviral Therapy in Africa (DART) trial cohort [randomized trial evaluating antiretroviral therapy (ART) management strategies] in Uganda, before they initiated ART (n = 276). A comparison group of ART-naive HIV-infected individuals was recruited from the Entebbe Cohort study (n = 159). Participants were interviewed and asked to rate his/her own health state using VAS; rank and evaluate HIV/AIDS predetermined health states using TTO and SG relative to an improved health state. Tools were tested for psychometrical properties. RESULTS: Women constituted 64% and 76% of the DART and Entebbe Cohorts. Mean age was 36.5 and 36.7 years, respectively. Participants could discriminate between predetermined HIV/AIDS health states. Deterioration in health status was associated with a reduction in rating scores (VAS), increased willingness to give up time (TTO) and acceptance of increased risk (SG) to achieve a better health state, independent of the participant's actual health state, as measured by CD4 cell counts. CONCLUSION: VAS, TTO and SG have good psychometric properties, making them good candidates for use in resource-constrained settings. Further research in a wider population is necessary to generate an evidence base with which to inform resource allocation decisions.


Asunto(s)
Infecciones por VIH/psicología , Estado de Salud , Perfil de Impacto de Enfermedad , Adulto , Antirretrovirales/economía , Antirretrovirales/uso terapéutico , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Análisis Costo-Beneficio , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/economía , Humanos , Masculino , Psicometría , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Uganda
20.
J Infect Dis ; 194(5): 666-9, 2006 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16897666

RESUMEN

We investigated the effect of RANTES polymorphisms on human immunodeficiency virus type 1 (HIV-1) disease progression in an urban population of Uganda. HIV-positive individuals homozygous for the INT1.1C polymorphism, which had been associated previously with low RANTES expression, were less likely to die than were those with other genotypes (hazard ratio, 0.53 [95% confidence interval, 0.33-0.83]; P=.007). This report of a non-human leukocyte antigen genetic association with HIV-1 and/or acquired immunodeficiency syndrome disease progression in an African population reveals a genetic effect different from that reported elsewhere for African Americans and may impact therapeutic strategies targeting the RANTES pathway in HIV infection.


Asunto(s)
Quimiocina CCL5/genética , Seropositividad para VIH/genética , Seropositividad para VIH/mortalidad , Polimorfismo Genético , Estudios de Cohortes , Seronegatividad para VIH , Seropositividad para VIH/fisiopatología , Homocigoto , Humanos , Análisis de Regresión , Análisis de Supervivencia , Resultado del Tratamiento , Uganda
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