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1.
Microb Genom ; 9(8)2023 08.
Article in English | MEDLINE | ID: mdl-37650865

ABSTRACT

Inferring the spatiotemporal spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via Bayesian phylogeography has been complicated by the overwhelming sampling bias present in the global genomic dataset. Previous work has demonstrated the utility of metadata in addressing this bias. Specifically, the inclusion of recent travel history of SARS-CoV-2-positive individuals into extended phylogeographical models has demonstrated increased accuracy of estimates, along with proposing alternative hypotheses that were not apparent using only genomic and geographical data. However, as the availability of comprehensive epidemiological metadata is limited, many of the current estimates rely on sequence data and basic metadata (i.e. sample date and location). As the bias within the SARS-CoV-2 sequence dataset is extensive, the degree to which we can rely on results drawn from standard phylogeographical models (i.e. discrete trait analysis) that lack integrated metadata is of great concern. This is particularly important when estimates influence and inform public health policy. We compared results generated from the same dataset, using two discrete phylogeographical models: one including travel history metadata and one without. We utilized sequences from Victoria, Australia, in this case study for two unique properties. Firstly, the high proportion of cases sequenced throughout 2020 within Victoria and the rest of Australia. Secondly, individual travel history was collected from returning travellers in Victoria during the first wave (January to May) of the coronavirus disease 2019 (COVID-19) pandemic. We found that the implementation of individual travel history was essential for the estimation of SARS-CoV-2 movement via discrete phylogeography models. Without the additional information provided by the travel history metadata, the discrete trait analysis could not be fit to the data due to numerical instability. We also suggest that during the first wave of the COVID-19 pandemic in Australia, the primary driving force behind the spread of SARS-CoV-2 was viral importation from international locations. This case study demonstrates the necessity of robust genomic datasets supplemented with epidemiological metadata for generating accurate estimates from phylogeographical models in datasets that have significant sampling bias. For future work, we recommend the collection of metadata in conjunction with genomic data. Furthermore, we highlight the risk of applying phylogeographical models to biased datasets without incorporating appropriate metadata, especially when estimates influence public health policy decision making.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , Phylogeography , COVID-19/epidemiology , Bayes Theorem , Metadata , Pandemics , Victoria
2.
JBMR Plus ; 5(2): e10446, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33615111

ABSTRACT

Most studies evaluating BMD in human immunodeficiency virus (HIV)-infected populations have focused on antiretroviral therapy (ART)-experienced patients. In this study, the association between HIV-1 and/or depot medroxyprogesterone acetate (DMPA) and BMD among untreated HIV-1-infected women in a resource-limited setting was assessed before long-term exposure to ART. The data were then compared with that of the 2005-2008 United States National Health and Nutrition Examination Survey data for non-Hispanic White and Black women. Women aged 18-35 years, recruited from health facilities in Kampala, Uganda, were classified based on their combination of HIV-1 status and DMPA use: (i) HIV-1-infected current DMPA users, (ii) HIV-1-infected previous DMPA users, (iii) HIV-1-infected nonhormonal-contraceptive users, and (iv) HIV-uninfected nonhormonal-contraceptive users. All HIV-1-infected women reported being ART-naïve at baseline. BMD was measured at the lumbar spine, total hip, and femoral neck using DXA. Multivariate linear regression was used to assess the association between HIV-1 and/or DMPA and BMD Z-scores. Baseline data were analyzed for 452 HIV-1-infected (220 nonhormonal users, and 177 current and 55 previous DMPA users) and 69 HIV-1-uninfected nonhormonal-contraceptive users. The mean age was 26.1 years (SD, 4.2) with a median duration of DMPA use among current users of 24.0 months [medians (interquartile range), 12-48]. A higher proportion of HIV-1-infected previous (12.7%) or current DMPA users (20.3%) and nonhormonal users (15.0%) had low BMD (Z-score ≤-2 at any of the three sites) compared with age-matched HIV-1-uninfected women (2.9%). HIV-1 infection and DMPA use were independently associated with significantly lower mean BMD Z-scores at all sites, with the greatest difference being among HIV-1-infected current DMPA users (5.6%-8.0%) versus uninfected nonhormonal users. Compared with non-Hispanic White and Black women, the Ugandan local reference population had generally lower mean BMD at all sites. Newer treatment interventions are needed to mitigate BMD loss in HIV-1-infected women in resource-limited settings. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

3.
AIDS ; 24(4): 557-61, 2010 Feb 20.
Article in English | MEDLINE | ID: mdl-20057308

ABSTRACT

OBJECTIVE: Single-dose nevirapine (NVP) (sdNVP) can reduce the risk of HIV vertical transmission. We assessed risk factors for NVP resistance in plasma and breast milk from sdNVP-exposed Ugandan women. METHODS: Samples were analyzed using the Roche AMPLICOR HIV-1 Monitor Test Kit, version 1.5, and the ViroSeq HIV-1 Genotyping System. NVP concentrations were determined by liquid chromatography with tandem mass spectroscopy. RESULTS: HIV genotypes (plasma and breast milk) were obtained for 30 women 4 weeks after sdNVP (HIV subtypes: 15A, 1C, 12D, two recombinant). NVP resistance was detected in 12 (40%) of 30 breast milk samples. There was a nonsignificant trend between detection of NVP resistance in breast milk and plasma (P = 0.06). There was no association of HIV resistance in breast milk with median maternal pre-NVP viral load or CD4 cell count, median breast milk viral load at 4 weeks, breast milk sodium more than 10 mmol/l, HIV subtype, or concentration of NVP in breast milk or plasma. CONCLUSION: NVP resistance was frequently detected in breast milk 4 weeks after sdNVP exposure. In this study, we were unable to identify specific factors associated with breast milk NVP resistance.


Subject(s)
Anti-HIV Agents/therapeutic use , Drug Resistance, Viral , HIV Infections/drug therapy , HIV-1/drug effects , Infectious Disease Transmission, Vertical/prevention & control , Milk, Human/virology , Nevirapine/therapeutic use , Adult , Anti-HIV Agents/analysis , Anti-HIV Agents/metabolism , Breast Feeding , CD4 Lymphocyte Count , Chromatography, Liquid , Drug Resistance, Viral/genetics , Female , Genotype , HIV Infections/blood , HIV Infections/transmission , HIV-1/genetics , HIV-1/isolation & purification , Humans , Milk, Human/chemistry , Nevirapine/analysis , Nevirapine/metabolism , Pregnancy , Uganda , Viral Load
4.
Lancet ; 372(9649): 1579-89, 2008 Nov 01.
Article in English | MEDLINE | ID: mdl-18984192

ABSTRACT

Planning for programme sustainability is a key contributor to health and development, especially in low-income and middle-income countries. A consensus evidence-based operational framework would facilitate policy and research advances in understanding, measuring, and improving programme sustainability. We did a systematic review of both conceptual frameworks and empirical studies about health-programme sustainability. On the basis of the review, we propose that sustainable health programmes are regarded as complex systems that encompass programmes, health problems targeted by programmes, and programmes' drivers or key stakeholders, all of which interact dynamically within any given context. We show the usefulness of this approach with case studies drawn from the authors' experience.


Subject(s)
Developing Countries , Health Planning/organization & administration , Health Promotion/organization & administration , Primary Health Care/organization & administration , Public Health , Total Quality Management/organization & administration , Health Planning/methods , Health Promotion/methods , Humans
5.
AIDS Res Hum Retroviruses ; 24(7): 911-7, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18593341

ABSTRACT

We describe changes in HIV-1 viral load, CD4+ T cell percentage, and incidence of drug resistance and factors associated with drug resistance for 134 children receiving antiretroviral therapy (ART) for approximately 1 year in Abidjan. Between August 1998 and September 2003, ART was initiated for 395 HIV-infected children ages 0-15 years in the Côte d'Ivoire national drug access initiative. All 1-year samples with detectable HIV RNA >1000 copies/ml were tested for HIV-1 drug resistance and changes in viral load and CD4+ T cell counts were also determined. At treatment initiation, 80% of children had CD4+ T cell percentages <15% and a median viral RNA load of 5.6 log copies/ml. The median age at treatment initiation was 7 years with only 25% of patients less than 4 years of age. Of the 134 children receiving therapy, 72 (54%) had undetectable viral load. The estimated 1-year viral load decline was 1.9 log10 copies/ml and the CD4+ T cell percentage increase was 10.9%. The estimated 1-year cumulative probability for developing any class of drug resistance was 0.44 (95% CI, 0.35, 0.53). In a multivariate analysis, the magnitude of virologic response to therapy was inversely associated with development of drug resistance. Children with less CD4+ T cell rise from baseline values and the use of dual therapy were also associated with the development of drug resistance. Guidelines are needed for the treatment of pediatric HIV infection in Africa in order to minimize the occurrence of drug resistance and enhance better virologic, immunologic, and clinical outcomes.


Subject(s)
Anti-HIV Agents/pharmacology , HIV Infections/drug therapy , HIV-1/drug effects , Adolescent , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , Child , Child, Preschool , Cote d'Ivoire , Drug Resistance, Viral , HIV Infections/immunology , HIV Infections/virology , HIV-1/genetics , Humans , Infant , Infant, Newborn , Treatment Outcome , Viral Load
6.
AIDS ; 17 Suppl 3: S87-93, 2003 Jul.
Article in English | MEDLINE | ID: mdl-14565614

ABSTRACT

OBJECTIVE: To describe the cost and outcome associated with the use of CD4 cell count and viral load tests as part of screening strategies to identify persons eligible for subsidized antiretroviral therapy (ART) in Côte d'Ivoire. METHODS: Empirical data from the Drug Access Initiative in Côte d'Ivoire (DAI-CI) were used to describe the laboratory cost of patient screening using sequential clinical staging, CD4 cell count, and viral load and the proportion of screened patients identified as eligible for ART. We also estimated costs modelling a parallel screening algorithm, across a range of laboratory costs and with current international recommendations to assess treatment eligibility. Benefit was defined as being found eligible for ART. RESULTS: Of the 2138 HIV-positive, ART-naive, adults who presented to the DAI-CI between July 1998 and July 2000, median CD4 cell count was 172 x 10(6) cells/microl. DAI-CI criteria identified 2057 (96%) of these persons eligible for antiretroviral treatment. In a serial screening algorithm, 75% were eligible by CDC clinical stage B or C; 18% by CD4 cell count less than 500 x 10(6) cells/microl; and an estimated 3.9% by a viral load greater than 10 000 copies/ml. Use of the current US recommendations and a serial algorithm would have resulted in 1977 (92%) persons eligible for ART: 75% by CDC clinical stage B or C; 15% by CD4 cell count less than 350 x 10(6) cells/microl (including 8% < 200 x 10(6) cells/microl); and an estimated 3.6% due to viral load greater than 55 000 copies/ml. Using DAI-CI criteria and heavily subsidized laboratory test costs, the addition of CD4 cell count to clinical criteria cost US dollar 50 (serial algorithm) and US dollar 203 (parallel algorithm) to identify each additional eligible person. Modelling current recommendations with a serial algorithm, CD4 cell count cost an average US dollar 62/eligible person (US recommendations) and US dollar 109 (WHO recommendations). The addition of viral load cost between US dollar 108 (serial algorithm DAI) to US dollar 1700 (parallel algorithm DAI) to identify each additional eligible person. CONCLUSION: In the African context of scarce resources and the huge unmet demands for voluntary HIV testing and for ART, simple screening strategies are needed to identify those most in need of ART. Health personnel should be trained to identify and refer clinically symptomatic persons. Viral load testing is of high cost and dubious benefit and should not be part of screening algorithms for initiating ART.


Subject(s)
Anti-HIV Agents/therapeutic use , Developing Countries , HIV Infections/diagnosis , HIV Infections/drug therapy , Mass Screening/methods , Adolescent , Adult , Algorithms , CD4 Lymphocyte Count , Cote d'Ivoire , Female , HIV Infections/immunology , Health Care Costs , Health Care Rationing/methods , Humans , Male , Mass Screening/economics , Patient Selection , Pilot Projects , Viral Load
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