Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
1.
Phys Sportsmed ; 49(3): 289-296, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32876504

RESUMO

PURPOSE: Normative values of common sport-related concussion assessment tools may assist clinical diagnosis and management. However, current baseline normative values are not representative of athletic participants across international domains. This study develops healthy baseline norms on the Balance Error Scoring System (BESS), and King-Devick (K-D), providing baseline reference values for professional Zambian football athletes. METHODS: Of the 125 male participants (aged 24.48 ± 5.41 years) screened for this study, 9 (7.2%) reported a previous history of concussion, 98 (78.4%) completed the Balance Error Scoring System and 88 (70.4%) completed the King-Devick. Descriptive statistics calculated for the BESS and the K-D test included mean, standard deviation, median, interquartile range (IQR), and percentiles ranks. MAIN FINDINGS: Participants scored a mean ± standard deviation of 10.15 ± 5.6 and a median [IQR] of 9 [6-12.25] errors on the total BESS and completed the K-D test in a mean ± standard deviation 56.85 ± 10.55 seconds and a median [IQR] 55.28 [48.7-64.8] seconds. CONCLUSIONS: Cross-cultural awareness and management of sport-related concussion are continuously improving the safety and well-being of athletic participants around the world. The diverse representation in these data may aid in interpretation of post-injury performance during sport-related concussion management in Zambia. This study develops baseline reference values currently lacking within African cultures and demonstrates the feasibility and global clinical utility of two sport-related concussion assessment resources.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Futebol , Adulto , Atletas , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Humanos , Masculino , Testes Neuropsicológicos , Futebol/lesões , Adulto Jovem , Zâmbia
2.
Phys Sportsmed ; 49(2): 165-170, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32605469

RESUMO

OBJECTIVE: Concussion is a global sport injury; however, this public health issue has yet to be studied across Africa. It is unknown if tests such as the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) Quick Test (QT) are culturally appropriate for implementation as part of a concussion screening protocol in Zambia or other African nations. Study objectives included: 1) establish that Zambian athletes are able to complete the iPad-based ImPACT QT with respect to language or cultural barriers that may exist, and 2) document baseline neurocognitive percentile ranks among Zambian football athletes on the ImPACT QT. METHODS: This study was completed with adult premiere league football athletes in Zambia (n = 125) aged 24.48 ± 5.41. Participants completed the ImPACT QT neurocognitive assessment prior to a preseason practice. Outcome measures were average performance on 3 factor scores: Motor Speed, Memory, and Attention Tracker, presented as percentile ranks using normative data built-into the ImPACT QT. RESULTS: Zambian athletes scored nearly two standard deviations below the mean on Motor Speed (7th percentile), using North American normative data. However, performance on Attention Tracker (44th percentile) and Memory (56th percentile) was within the average range. CONCLUSION: Results of the current study show that Zambian athletes are able to complete the ImPACT QT, despite any language or cultural differences that may exist. In addition, preliminary percentile ranks suggest Zambian football athletes have average scores on Attention and Memory and below average scores on Motor Speed. These data are the first to explore Zambian athletes' performance on a cognitive concussion measure.


Assuntos
Traumatismos em Atletas , Futebol Americano , Adulto , Atletas , Comparação Transcultural , Humanos , Testes Neuropsicológicos , Zâmbia
3.
J Int AIDS Soc ; 23 Suppl 3: e25522, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32602618

RESUMO

INTRODUCTION: Couples' voluntary HIV counselling and testing (CVCT) is a high-impact HIV prevention intervention in Rwanda and Zambia. Our objective was to model the cost-per-HIV infection averted by CVCT in six African countries guided by an HIV prevention cascade framework. The HIV prevention cascade as yet to be applied to evaluating CVCT effectiveness or cost-effectiveness. METHODS: We defined a priority population for CVCT in Africa as heterosexual adults in stable couples. Based on our previous experience nationalizing CVCT in Rwanda and scaling-up CVCT in 73 clinics in Zambia, we estimated HIV prevention cascade domains of motivation for use, access and effectiveness of CVCT as model parameters. Costs-per-couple tested were also estimated based on our previous studies. We used these parameters as well as country-specific inputs to model the impact of CVCT over a five-year time horizon in a previously developed and tested deterministic compartmental model. We consider six countries across Africa with varied HIV epidemics (South Africa, Zimbabwe, Kenya, Tanzania, Ivory Coast and Sierra Leone). Outcomes of interest were the proportion of HIV infections averted by CVCT, nationwide CVCT implementation costs and costs-per-HIV infection averted by CVCT. We applied 3%/year discounting to costs and outcomes. Univariate and Monte Carlo multivariate sensitivity analyses were conducted. RESULTS: We estimated that CVCT could avert between 54% (Sierra Leone) and 62% (South Africa) of adult HIV infections. Average costs-per-HIV infection averted were lowest in Zimbabwe ($550) and highest in South Africa ($1272). Nationwide implementations would cost between 7% (Kenya) and 21% (Ivory Coast) of a country's President's Emergency Plan for AIDS Relief (PEPFAR) budget over five years. In sensitivity analyses, model outputs were most sensitive to estimates of cost-per-couple tested; the proportion of adults in heterosexual couples and HIV prevention cascade domains of CVCT motivation and access. CONCLUSIONS: Our model indicates that nationalized CVCT could prevent over half of adult HIV infections for 7% to 21% of the modelled countries' five-year PEPFAR budgets. While other studies have indicated that CVCT motivation is high given locally relevant promotional and educational efforts, without required indicators, targets and dedicated budgets, access remains low.


Assuntos
Aconselhamento/economia , Infecções por HIV/prevenção & controle , Parceiros Sexuais , Adulto , África/epidemiologia , Análise Custo-Benefício , Feminino , Heterossexualidade , Humanos , Masculino , Modelos Econômicos , Estudos Retrospectivos
4.
Int J Epidemiol ; 48(1): 217-227, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358840

RESUMO

BACKGROUND: The impact and cost-effectiveness of couples' voluntary HIV counselling and testing (CVCT) has not been quantified in real-world settings. We quantify cost-per-HIV-infection averted by CVCT in Zambia from the donor's perspective. METHODS: From 2010 to 2016, CVCT was established in 73 Zambian government clinics. The cost-per-HIV-infection averted (CHIA) of CVCT was calculated using observed expenditures and effectiveness over longitudinal follow-up. These observed measures parameterized hypothetical 5-year nationwide implementations of: 'CVCT'; 'treatment-as-prevention (TasP) for discordant couples' identified by CVCT; and 'population TasP' for all HIV+ cohabiting persons identified by individual testing. RESULTS: In all, 207 428 couples were tested (US $52/couple). Among discordant couples in which HIV+ partners self-reported antiretroviral therapy (ART), HIV incidence was 8.5/100 person-years before and 1.8/100 person-years after CVCT (79% reduction). Corresponding reductions for non-ART-using discordant and concordant negative couples were 63% and 47%, respectively. CVCT averted an estimated 58% of new infections at US $659 CHIA. In nationwide implementation models, CVCT would prevent 17 times the number of infections vs 'TasP for discordant couples' at 86% of the cost, and nine times the infections vs 'population TasP' at 28% of the cost. CONCLUSIONS: CVCT is a cost-effective, feasible prevention strategy in Zambia. We demonstrate the novel, added effectiveness of providing CVCT to ART users, for whom ART use alone only partially mitigated transmission risk. Our results indicate a major policy shift (supporting development of CVCT indicators, budgets and targets) and have clinical implications (suggesting promotion of CVCT in ART clinics as a high-impact prevention strategy).


Assuntos
Aconselhamento/organização & administração , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Programas de Rastreamento/economia , Parceiros Sexuais , Adulto , Antirretrovirais/uso terapêutico , Custos e Análise de Custo , Feminino , Infecções por HIV/economia , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Programas Voluntários , Zâmbia/epidemiologia
5.
World J Hepatol ; 10(9): 622-628, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30310540

RESUMO

AIM: To characterize antiviral therapy eligibility among hepatitis B virus (HBV)-infected adults at a university hospital in Zambia. METHODS: Hepatitis B surface antigen-positive adults (n = 160) who were HIV-negative and referred to the hospital after a routine or clinically-driven HBV test were enrolled. Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), platelet count, hepatitis B e-antigen, and HBV DNA were measured. Liver fibrosis/cirrhosis was assessed by physical examination, AST-to-platelet ratio index, and transient elastography. In antiviral therapy-naïve individuals, we described HBV stages and antiviral therapy eligibility per World Health Organization (WHO) and by HBV test (routine vs clinical). Elevated ALT was > 19 in women and > 30 U/L in men. Among treatment-experienced individuals, we described medication side effects, adherence, and viral suppression. RESULTS: The median age was 33 years, 71.9% were men, and 30.9% were diagnosed with HBV through a clinically-driven test with the remainder identified via routine testing (at the blood bank, community events, etc.). Among 120 treatment-naïve individuals, 2.5% were categorized as immune tolerant, 11.7% were immune active, 35.6% were inactive carriers, and 46.7% had an indeterminate phenotype. Per WHO guidelines, 13 (10.8%) were eligible for immediate antiviral therapy. The odds of eligibility were eight times higher for those diagnosed at clinical vs routine settings (adjusted odds ratio, 8.33; 95%CI: 2.26-29.41). Among 40 treatment-experienced HBV patients, virtually all took tenofovir, and a history of mild side effects was reported in 20%. Though reported adherence was good, 12 of 29 (41.4%) had HBV DNA > 20 IU/mL. CONCLUSION: Approximately one in ten HBV-monoinfected Zambians were eligible for antivirals. Many had indeterminate phenotype and needed clinical follow-up.

6.
PLoS One ; 13(1): e0189869, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29364895

RESUMO

INTRODUCTION: Attempts to conceive and pregnancy may increase HIV transmission to sex partners and infants. Our study evaluated the association between fertility intentions and HIV acquisition among Zambian HIV-serodiscordant couples. METHODS: We collected demographic, behavioral, clinical exposures, and data on fertility intentions in a cohort of HIV-serodiscordant couples in Lusaka, Zambia from 2005 to 2012. We evaluated factors associated with fertility intentions stratified by gender using multivariable logistic regression. Multivariable Cox proportional hazard models were used to evaluate the associations between fertility intentions and HIV acquisition controlling for a priori confounders and covariates that substantially (>10%) changed the effect estimates in univariate analyses. RESULTS: Among 1,029 serodiscordant couples, 311 agreed that they wanted children in the future (30%), 368 agreed they did not want children (36%), and 344 couples disagreed about having children (34%), with men more likely than women to want children. Women wanting child(ren) was associated with increased odds of baseline pregnancy (adjusted odds ratio [aOR] = 4.80 (95% confidence interval [CI] = 2.93, 7.85)), fewer previous pregnancies (aOR = 0.85 per additional pregnancy (95% CI = 0.78, 0.93)), and partner fertility intention (aOR = 2.89 (95% CI = 2.14, 3.91)) adjusting for woman's age, literacy, years cohabiting and HIV status. Men wanting child(ren) was associated with younger age (aOR = 0.96 per year (95% CI = 0.93, 0.99)), fewer years cohabiting (aOR = 0.95 (95% CI = 0.92, 0.98)), number of previous partners' pregnancies (aOR = 0.90 (95% CI = 0.82, 0.98)), and partner fertility intention (aOR = 3.00 (95% CI = 2.21, 4.07)) adjusting for partner's age, literacy, HIV status and partner's baseline pregnancy. In adjusted survival analyses, HIV-negative women were more likely to seroconvert if they themselves wanted children (aHR = 2.36 (95% CI = 1.41, 3.96)) vs. did not want children, or if their partner wanted children (aHR = 2.34 (95% CI = 1.33, 4.11)) vs. did not want children, or if the couple agreed that they wanted children (aHR = 2.08 (95% CI = 1.01, 4.30)), adjusting for women's age, women's literacy, previous pregnancies and time in study. HIV-negative men were more likely to seroconvert if their female partner wanted a child in the next 12-months (aHR = 1.94 (95% CI = 1.02, 3.68)) vs. did not want children, and when both partners wanted children (aHR = 2.02 (CI = 1.09, 3.73)) vs. they did not want children, adjusting for men's age and literacy, couple income, number of live children, male circumcision status and time in study. CONCLUSION: Women had increased risk of HIV acquisition if they and/or their partner wanted a child, while men had increased risk of HIV acquisition when their partner or if both partners agreed that they wanted children. Safer-conception interventions are needed to protect HIV uninfected women and men from HIV acquisition in HIV-serodiscordant couples who want children.


Assuntos
Tomada de Decisões , Serviços de Planejamento Familiar , Infecções por HIV/fisiopatologia , Infecções por HIV/transmissão , Parceiros Sexuais , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem , Zâmbia
7.
AIDS Behav ; 22(7): 2386, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28956345

RESUMO

The article Risky Sex and HIV Acquisition Among HIV Serodiscordant Couples in Zambia, 2002-2012: What Does Alcohol Have To Do With It?, written by Dvora Joseph Davey, William Kilembe, Kristin M. Wall, Naw Htee Khu, Ilene Brill, Bellington Vwalika, Elwyn Chomba, Joseph Mulenga, Amanda Tichacek, Marjan Javanbakht, W. Scott Comulada, Susan Allen, Pamina M. Gorbach, was originally published Online First without open access. After publication in volume 21, issue 7, pages 1892-1903, the author decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to

8.
J Acquir Immune Defic Syndr ; 76(2): 123-131, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28737591

RESUMO

OBJECTIVE: Evaluate the incidence and predictors of HIV acquisition from outside partners in serodiscordant couples. METHODS: Demographic, behavioral, and clinical exposures were measured quarterly in a cohort of serodiscordant cohabiting couples in Zambia from 1995 to 2012 (n = 3049). Genetic analysis classified incident infections as those acquired from the study partner (linked) or acquired from an outside partner (unlinked). Factors associated with time to unlinked HIV infection were evaluated using multivariable Cox proportional hazards regression stratified by sex. RESULTS: There were 100 unlinked infections in couples followed for a median of 806 days. Forty-five infections occurred in women [1.85/100 couple-years; 95% confidence interval (CI): 1.35 to 2.47]. Risk of female unlinked infection (vs. nonseroconverting females) was associated with reporting being drunk weekly/daily vs. moderate/nondrinkers at baseline [adjusted hazard ratio (aHR) = 5.44; 95% CI: 1.03 to 28.73], genital ulcers (aHR = 6.09; 95% CI: 2.72 to 13.64), or genital inflammation (aHR = 11.92; 95% CI: 5.60 to 25.37) during follow-up adjusting for age, years cohabiting, income, contraceptive use, previous pregnancies, history of sexually transmitted infections, and condomless sex with study partner. Fifty-five infections occurred in men (1.82/100 couple-years; 95% CI: 1.37 to 2.37). Risk of male unlinked infection was associated with genital inflammation (aHR = 8.52; 95% CI: 3.82 to 19.03) or genital ulceration (aHR = 2.31; 95% CI: 2.05 to 8.89), reporting ≥1 outside sexual partner (aHR = 3.86; 95% CI: 0.98 to 15.17) during follow-up, and reporting being drunk weekly/daily vs. moderate/nondrinkers at baseline (aHR = 3.84; 95% CI: 1.28 to 11.55), controlling for age, income, circumcision status, and history of sexually transmitted infection. CONCLUSIONS: Predictors of unlinked infection in serodiscordant relationships were alcohol use, genital inflammation, and ulceration. Causes of genital inflammation and ulceration should be screened for and treated in HIV-negative individuals. Counseling on risk of alcohol use and sex with outside partners should be discussed with couples where 1 or both are HIV-negative, including in counseling on use of pre-exposure prophylaxis to prevent HIV acquisition in the HIV-negative partner (when feasible and affordable).


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Adulto , Consumo de Bebidas Alcoólicas , Feminino , Seguimentos , Doenças dos Genitais Femininos/epidemiologia , Doenças dos Genitais Masculinos/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Masculino , Profilaxia Pré-Exposição , Estudos Prospectivos , Fatores de Risco , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/epidemiologia , Adulto Jovem , Zâmbia/epidemiologia
9.
Int J Epidemiol ; 46(5): 1593-1606, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28402442

RESUMO

Background: Studies have demonstrated the role of ulcerative and non-ulcerative sexually transmitted infections (STI) in HIV transmission/acquisition risk; less is understood about the role of non-specific inflammatory genital abnormalities. Methods: HIV-discordant heterosexual Zambian couples were enrolled into longitudinal follow-up (1994-2012). Multivariable models estimated the effect of genital ulcers and inflammation in both partners on time-to-HIV transmission within the couple. Population-attributable fractions (PAFs) were calculated. Results: A total of 207 linked infections in women occurred over 2756 couple-years (7.5/100 CY) and 171 in men over 3216 CY (5.3/100 CY). Incident HIV among women was associated with a woman's non-STI genital inflammation (adjusted hazard ratio (aHR) = 1.55; PAF = 8%), bilateral inguinal adenopathy (BIA; aHR = 2.33; PAF = 8%), genital ulceration (aHR = 2.08; PAF = 7%) and the man's STI genital inflammation (aHR = 3.33; PAF = 5%), BIA (aHR = 3.35; PAF = 33%) and genital ulceration (aHR = 1.49; PAF = 9%). Infection among men was associated with a man's BIA (aHR = 4.11; PAF = 22%) and genital ulceration (aHR = 3.44; PAF = 15%) as well as with the woman's non-STI genital inflammation (aHR = 1.92; PAF = 13%) and BIA (aHR = 2.76; PAF = 14%). In HIV-M+F- couples, the man being uncircumcised. with foreskin smegma. was associated with the woman's seroconversion (aHR = 3.16) relative to being circumcised. In F+M- couples, uncircumcised men with BIA had an increased hazard of seroconversion (aHR = 13.03 with smegma and 4.95 without) relative to being circumcised. Self-reporting of symptoms was low for ulcerative and non-ulcerative STIs. Conclusions: Our findings confirm the role of STIs and highlight the contribution of non-specific genital inflammation to both male-to-female and female-to-male HIV transmission/acquisition risk. Studies are needed to characterize pathogenesis of non-specific inflammation including inguinal adenopathy. A better understanding of genital practices could inform interventions.


Assuntos
Genitália/patologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Heterossexualidade , Adulto , Preservativos/estatística & dados numéricos , Características da Família , Feminino , Humanos , Inflamação/complicações , Estudos Longitudinais , Masculino , Análise Multivariada , Fatores de Risco , Zâmbia/epidemiologia
10.
AIDS Behav ; 21(7): 1892-1903, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28243934

RESUMO

In this paper we evaluate the effects of heavy alcohol consumption on sexual behavior, HIV acquisition, and antiretroviral treatment (ART) initiation in a longitudinal open cohort of 1929 serodiscordant couples in Lusaka, Zambia from 2002 to 2012. We evaluated factors associated with baseline heavy alcohol consumption and its association with condomless sex with the study partner, sex outside of the partnership, and ART initiation using multivariable logistic regression. We estimated the effect of alcohol consumption on HIV acquisition using multivariable Cox models. Baseline factors significantly associated with women's heavy drinking (drunk weekly or more in 12-months before enrollment) included woman's older age (adjusted prevalence odds ratio [aPOR] = 1.04), partner heavy drinking (aPOR = 3.93), and being HIV-infected (aPOR = 2.03). Heavy drinking among men was associated with less age disparity with partner (aPOR per year disparity = 0.97) and partner heavy drinking (aPOR = 1.63). Men's being drunk daily (aOR = 1.18), women's being drunk less than monthly (aOR = 1.39) vs. never drunk and being in a male HIV-negative and female HIV-positive union (aOR = 1.45) were associated with condomless sex. Heavy alcohol use was associated with having 1 or more outside sex partners among men (aOR drunk daily = 1.91, drunk weekly = 1.32, drunk monthly = 2.03 vs. never), and women (aOR drunk monthly = 2.75 vs. never). Being drunk weekly or more increased men's risk of HIV acquisition (adjusted hazard ratio [aHR] = 1.72). Men and women being drunk weekly or more was associated (p < 0.1) with women's seroconversion (aHR = 1.42 and aHR = 3.71 respectively). HIV-positive women who were drunk monthly or more had lower odds of initiating ART (aOR = 0.83; 95% CI = 0.70-0.99) adjusting for age, months since baseline and previous pregnancies. Individuals in HIV-serodiscordant couples who reported heavy drinking had more outside sex partnerships and condomless sex with their study partner and were more likely to acquire HIV. HIV-positive women had lower odds of initiating ART if they were heavy drinkers.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Intoxicação Alcoólica/epidemiologia , Infecções por HIV/transmissão , Sexo sem Proteção/estatística & dados numéricos , Adulto , Fatores Etários , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Adulto Jovem , Zâmbia/epidemiologia
11.
Sex Transm Infect ; 93(4): 259-266, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28082662

RESUMO

BACKGROUND: We present temporal trends in self-reported and biological markers of unprotected sex and sex with concurrent partners in discordant couples receiving couples' voluntary HIV counselling and testing (CVCT). METHODS: Heterosexual Zambian HIV-serodiscordant couples were enrolled into longitudinal follow-up in an open cohort (1994-2012). Multivariable Anderson-Gill models explored predictors of self-report and biological indicators of unprotected sex within (including sperm on a vaginal swab, incident pregnancy or incident linked HIV infection) and outside (including self-report, STI and unlinked HIV infection) the union. Measures of secular trends in baseline measures were also examined. RESULTS: At enrolment of 3049 couples, men were 35 years old on average, women were 29 years, and couples had been together for an average of 7 years. M+F- couples reported an average of 16.6 unprotected sex acts in the 3 months prior to enrolment (pre-CVCT), dropping to 5.3 in the >0-3 month interval, and 2.0 in >6 month intervals (p-trend <0.001). Corresponding values for M-F+ couples were 22.4 unprotected sex acts in the 3 months prior enrolment, dropping to 5.2 in the >0-3 month interval, and 3.1 in >6 month intervals (p-trend <0.001). Significant reductions in self-report and biological markers of outside partners were also noted. Predictors of unprotected sex between study partners after CVCT included prevalent pregnancy (adjusted HR, aHR=1.6-1.9); HIV+ men being circumcised (aHR=1.2); and HIV- women reporting sex with outside partners (aHR=1.3), alcohol (aHR=1.2), injectable (aHR=1.4) or oral (aHR=1.4) contraception use. Fertility intentions were also predictive of unprotected sex (aHR=1.2-1.4). Secular trends indicated steady declines in reported outside partners and STIs. CONCLUSION: Reductions in self-reported unprotected sex after CVCT were substantial and sustained. Reinforced risk-reduction counselling in pregnant couples, couples desiring children and couples with HIV- women having outside partners or using alcohol or injectable or oral contraception are indicated.


Assuntos
Preservativos/estatística & dados numéricos , Aconselhamento , Características da Família , Soropositividade para HIV/psicologia , Comportamento de Redução do Risco , Adulto , Comportamento Contraceptivo , Aconselhamento/métodos , Feminino , Seguimentos , Heterossexualidade , Humanos , Estudos Longitudinais , Masculino , Cooperação do Paciente/estatística & dados numéricos , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Zâmbia
12.
J Acquir Immune Defic Syndr ; 71(3): 345-52, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26379070

RESUMO

BACKGROUND: Some studies suggest that hormonal contraception, pregnancy, and/or breastfeeding may influence rates of HIV disease progression. METHODS: From 1994 to 2012, HIV discordant couples recruited at couples' voluntary HIV counseling and testing centers in Lusaka were followed 3-monthly. Multivariate survival analyses explored associations between time-varying contraception, pregnancy, and breastfeeding and 2 outcomes among HIV-positive women: (1) time to death and (2) time to antiretroviral treatment (ART) initiation. RESULTS: Among 1656 female seropositive, male seronegative couples followed for 3359 person-years (PY), 224 women died [6.7/100 PY; 95% confidence interval (CI): 5.8 to 7.6]. After 2003, 290 women initiated ART (14.5/100 PY; 95% CI: 12.9 to 16.2). In a multivariate model of time to death, hormonal implant [adjusted hazard ratio (aHR) = 0.30; 95% CI: 0.10 to 0.98] and injectable (aHR = 0.59; 95% CI: 0.36 to 0.97) were significantly protective relative to nonhormonal method use, whereas oral contraceptive pill (OCP) use was not (aHR = 1.08; 95% CI: 0.74 to 1.57) controlling for baseline HIV disease stage, time-varying pregnancy, time-varying breastfeeding, and year of enrollment. In a multivariate model of time-to-ART initiation, implant was significantly protective (aHR = 0.54; 95% CI: 0.31 to 0.95), whereas OCP (aHR = 0.70; 95% CI: 0.44 to 1.10) and injectable (aHR = 0.85; 95% CI: 0.55 to 1.32) were not relative to nonhormonal method use controlling for variables above, woman's age, and literacy. Pregnancy was not significantly associated with death (aHR = 1.07; 95% CI: 0.68 to 1.66) or ART initiation (aHR = 1.24; 95% CI: 0.83 to 1.86), whereas breastfeeding was protective for death (aHR = 0.34; 95% CI: 0.19 to 0.62) and ART initiation (aHR = 0.49; 95% CI: 0.29 to 0.85). CONCLUSIONS: Hormonal implants and injectables significantly predicted lower mortality; implants were protective for ART initiation. OCPs and pregnancy were not associated with death or ART initiation, whereas breastfeeding was protective for both. Findings from this 18-year cohort study suggest that (1) HIV-positive women desiring pregnancy can be counseled to do so and breastfeed and (2) all effective contraceptive methods, including injectables and implants, should be promoted to prevent unintended pregnancy.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Aleitamento Materno , Anticoncepcionais Femininos/farmacologia , Infecções por HIV/patologia , Adulto , Estudos de Coortes , Progressão da Doença , Implantes de Medicamento , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Masculino , Análise Multivariada , Gravidez , Modelos de Riscos Proporcionais , Fatores de Risco , Zâmbia/epidemiologia
13.
PLoS One ; 9(8): e105089, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25118593

RESUMO

OBJECTIVES: To investigate the effect of seasonal variation on adult clinical laboratory parameters in Rwanda, Zambia, and Uganda and determine its implications for HIV prevention and other clinical trials. METHODS: Volunteers in a cross-sectional study to establish laboratory reference intervals were asked to return for a seasonal visit after the local season had changed from dry to rainy or vice versa. Volunteers had to be clinically healthy, not pregnant and negative for HIV, Hepatitis B and C, and syphilis infection at both visits. At each visit, blood was taken for measurement of hemoglobin, haematocrit, mean corpuscular volume, red blood cells, platelets, total white blood cells (WBC), neutrophils, lymphocytes, monocytes, eosinophils, basophils, CD4/CD8 T cells, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, direct bilirubin, total bilirubin, total immunoglobulin gamma, total protein, creatinine, total amylase, creatine phosphokinase and lactate dehydrogenase (LDH). Consensus dry season reference intervals were applied to rainy season values (and vice versa) and the proportion of 'out-of-range' values determined. Percentage differences between dry and rainy season parameter mean values were estimated. RESULTS: In this cohort of 903 volunteers, less than 10.0% of consensus parameter (except LDH) values in one season were "out-of-range" in the other. Twenty-two (22) percent of rainy season LDH values fell outside of the consensus dry season interval with the higher values observed in the rainy season. Variability between consensus seasonal means ranged from 0.0% (total WBC, neutrophils, monocytes, basophils, and direct bilirubin) to 40.0% (eosinophils). Within sites, the largest seasonal variations were observed for monocytes (Masaka, 11.5%), LDH (Lusaka, 21.7%), and basophils (Kigali, 22.2%). CONCLUSIONS: Seasonality had minimal impact on adult clinical laboratory parameter values in Rwanda, Zambia, and Uganda. Seasonal variation may not be an important factor in the evaluation of adult clinical laboratory parameters in HIV prevention and other clinical trials in these countries.


Assuntos
Infecções por HIV/sangue , Infecções por HIV/prevenção & controle , Adolescente , Adulto , Clima , Estudos Transversais , Feminino , HIV/isolamento & purificação , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Testes Hematológicos , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Ruanda/epidemiologia , Estações do Ano , Uganda/epidemiologia , Adulto Jovem , Zâmbia/epidemiologia
14.
Virology ; 462-463: 295-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25004405

RESUMO

We have previously shown that HIV-1 superinfected Zambian seroconverters mount low binding and neutralizing antibody responses to their primary HIV-1 infecting virus, which could increase susceptibility to re-infection. Here, we investigated if antibody-dependent cellular cytotoxicity (ADCC), a process by which virus-infected cells are killed, was also reduced. Superinfected individuals exhibited low ADCC activity compared to non-superinfected individuals, but similar levels of CMV-reactive binding antibodies, suggesting superinfected individuals are capable of generating and maintaining virus-specific antibodies.


Assuntos
Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Imunidade Celular , Superinfecção/imunologia , Humanos
16.
AIDS ; 27(11): 1717-23, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23525031

RESUMO

BACKGROUND: Human leukocyte allele (HLA) class I polymorphism has the greatest impact of human genetic variation on viral load set point. A substantial part of this effect is due to the action of HLA-B and HLA-C alleles. With few exceptions the role of HLA-A molecules in immune control of HIV is unclear. METHODS: We here study HLA-A*68:02, one of the most highly prevalent HLA-A alleles in C-clade infected sub-Saharan African populations, and one that plays a prominent role in the HIV-specific CD8 T-cell responses made against the virus. RESULTS: We define eight epitopes restricted by this allele and propose the peptide binding motif for HLA-A*68:02. Although one of these epitopes almost exactly overlaps an HLA-B*57-restricted epitope in Gag linked with immune control of HIV, this HLA-A*68:02-restricted Gag-TA10 response imposed only weak selection pressure on the virus and was not associated with significantly lower viral setpoint. The only HLA-A*68:02-restricted responses imposing strong selection pressure on HIV were in the flanking regions of Pol-EA8 and Pol-EA11 and within the Vpr-EV10 epitope (P  =  8 × 10). However, targeting of this latter epitope was associated with significantly higher viral loads (P  =  0.003), suggesting lack of efficacy. CONCLUSION: This study is consistent with previous data showing that HLA-A-restricted Gag-specific responses can impose selection pressure on HIV. In the case of HLA-A*68:02 the Gag response is subdominant, and apparently has little impact in natural infection. However, these data suggest the potential for high frequency vaccine-induced Gag responses restricted by this allele to have significant antiviral efficacy in vaccine recipients.


Assuntos
Linfócitos T CD8-Positivos/imunologia , HIV/genética , HIV/imunologia , Antígenos HLA-A/imunologia , Seleção Genética , Linfócitos T Citotóxicos/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , África Subsaariana , Epitopos/imunologia , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares
17.
Clin Infect Dis ; 56(12): 1829-37, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23487377

RESUMO

BACKGROUND: Syphilis continues to be a common sexually transmitted infection, despite the availability of inexpensive and effective treatment. Infection in human immunodeficiency virus (HIV)-discordant couples is important because syphilis increases the risk of HIV acquisition. Current US treatment guidelines recommend 1 dose of benzathine penicillin for early syphilis, irrespective of HIV status, but data from coinfected patients are limited. METHODS: Retrospective analysis of 1321 individuals in 2 African HIV-discordant couple cohorts was performed. Cox proportional hazards analysis and multivariable modeling were used to assess predictors of serologic response to treatment at 180 days and 400 days. Modeling was performed for all episodes of positive rapid plasma reagin (RPR) test results and on a subset with higher RPR titers (≥1:4). RESULTS: A total of 1810 episodes of syphilis among 1321 individuals were treated with penicillin between 2002 and 2008. Although a positive RPR was more common in the HIV-infected partners, HIV infection did not impact the likelihood of serologic response to therapy (odds ratio [OR], 1.001; P = .995). By 400 days, 67% had responded to therapy, 27% were serofast, and 6.5% had documented reinfection. Prevalent infections were more likely to remain serofast than incident infections (33% vs 20% at 400 days). CONCLUSIONS: In 2 HIV-serodiscordant couple cohorts in Africa, incident syphilis had a very good likelihood of response to penicillin therapy, irrespective of HIV infection. This supports current Centers for Disease Control and Prevention treatment guidelines. A high proportion of prevalent RPR-positive infections remain serofast despite treatment.


Assuntos
Infecções por HIV/microbiologia , Cônjuges/estatística & dados numéricos , Sífilis/tratamento farmacológico , Sífilis/virologia , Adolescente , Adulto , Antitreponêmicos/uso terapêutico , Feminino , Infecções por HIV/epidemiologia , Soronegatividade para HIV , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Penicilinas/uso terapêutico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Ruanda/epidemiologia , Sífilis/epidemiologia , Resultado do Tratamento , Zâmbia/epidemiologia
18.
PLoS Pathog ; 8(11): e1003041, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209412

RESUMO

Initial studies of 88 transmission pairs in the Zambia Emory HIV Research Project cohort demonstrated that the number of transmitted HLA-B associated polymorphisms in Gag, but not Nef, was negatively correlated to set point viral load (VL) in the newly infected partners. These results suggested that accumulation of CTL escape mutations in Gag might attenuate viral replication and provide a clinical benefit during early stages of infection. Using a novel approach, we have cloned gag sequences isolated from the earliest seroconversion plasma sample from the acutely infected recipient of 149 epidemiologically linked Zambian transmission pairs into a primary isolate, subtype C proviral vector, MJ4. We determined the replicative capacity (RC) of these Gag-MJ4 chimeras by infecting the GXR25 cell line and quantifying virion production in supernatants via a radiolabeled reverse transcriptase assay. We observed a statistically significant positive correlation between RC conferred by the transmitted Gag sequence and set point VL in newly infected individuals (p = 0.02). Furthermore, the RC of Gag-MJ4 chimeras also correlated with the VL of chronically infected donors near the estimated date of infection (p = 0.01), demonstrating that virus replication contributes to VL in both acute and chronic infection. These studies also allowed for the elucidation of novel sites in Gag associated with changes in RC, where rare mutations had the greatest effect on fitness. Although we observed both advantageous and deleterious rare mutations, the latter could point to vulnerable targets in the HIV-1 genome. Importantly, RC correlated significantly (p = 0.029) with the rate of CD4+ T cell decline over the first 3 years of infection in a manner that is partially independent of VL, suggesting that the replication capacity of HIV-1 during the earliest stages of infection is a determinant of pathogenesis beyond what might be expected based on set point VL alone.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1 , Polimorfismo Genético , Replicação Viral/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular , Feminino , Seguimentos , Genoma Viral/genética , Genoma Viral/imunologia , Infecções por HIV/epidemiologia , Infecções por HIV/genética , HIV-1/patogenicidade , HIV-1/fisiologia , Humanos , Masculino , Mutação , Replicação Viral/genética , Zâmbia/epidemiologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética
19.
BMJ Open ; 2(5)2012.
Artigo em Inglês | MEDLINE | ID: mdl-22956641

RESUMO

OBJECTIVES: Hypothesising that couples' voluntary counselling and testing (CVCT) promotions can increase CVCT uptake, this study identified predictors of successful CVCT promotion in Lusaka, Zambia. DESIGN: Cohort study. SETTING: Lusaka, Zambia. PARTICIPANTS: 68 influential network leaders (INLs) identified 320 agents (INAs) who delivered 29 119 CVCT invitations to heterosexual couples. INTERVENTION: The CVCT promotional model used INLs who identified INAs, who in turn conducted community-based promotion and distribution of CVCT invitations in two neighbourhoods over 18 months, with a mobile unit in one neighbourhood crossing over to the other mid-way through. PRIMARY OUTCOME: The primary outcome of interest was couple testing (yes/no) after receipt of a CVCT invitation. INA, couple and invitation characteristics predictive of couples' testing were evaluated accounting for two-level clustering. RESULTS: INAs delivered invitations resulting in 1727 couples testing (6% success rate). In multivariate analyses, INA characteristics significantly predictive of CVCT uptake included promoting in community-based (adjusted OR (aOR)=1.3; 95% CI 1.0 to 1.8) or health (aOR=1.5; 95% CI 1.2 to 2.0) networks versus private networks; being employed in the sales/service industry (aOR=1.5; 95% CI 1.0 to 2.1) versus unskilled manual labour; owning a home (aOR=0.7; 95% CI 0.6 to 0.9) versus not; and having tested for HIV with a partner (aOR=1.4; 95% CI 1.1 to 1.7) or alone (aOR=1.3; 95% CI 1.0 to 1.6) versus never having tested. Cohabiting couples were more likely to test (aOR=1.4; 95% CI 1.2 to 1.6) than non-cohabiting couples. Context characteristics predictive of CVCT uptake included inviting couples (aOR=1.2; 95% CI 1.0 to 1.4) versus individuals; the woman (aOR=1.6; 95% CI 1.2 to 2.2) or couple (aOR=1.4; 95% CI 1.0 to 1.8) initiating contact versus the INA; the couple being socially acquainted with the INA (aOR=1.6; 95% CI 1.4 to 1.9) versus having just met; home invitation delivery (aOR=1.3; 95% CI 1.1 to 1.5) versus elsewhere; and easy invitation delivery (aOR=1.8; 95% CI 1.4 to 2.2) versus difficult as reported by the INA. CONCLUSIONS: This study demonstrated the ability of influential people to promote CVCT and identified agent, couple and context-level factors associated with CVCT uptake in Lusaka, Zambia. We encourage the development of CVCT promotions in other sub-Saharan African countries to support sustained CVCT dissemination.

20.
Retrovirology ; 9: 76, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22995123

RESUMO

BACKGROUND: The potential role of antibodies in protection against intra-subtype HIV-1 superinfection remains to be understood. We compared the early neutralizing antibody (NAb) responses in three individuals, who were superinfected within one year of primary infection, to ten matched non-superinfected controls from a Zambian cohort of subtype C transmission cases. Sequence analysis of single genome amplified full-length envs from a previous study showed limited diversification in the individuals who became superinfected with the same HIV-1 subtype within year one post-seroconversion. We hypothesized that this reflected a blunted NAb response, which may have made these individuals more susceptible to superinfection. RESULTS: Neutralization assays showed that autologous plasma NAb responses to the earliest, and in some cases transmitted/founder, virus were delayed and had low to undetectable titers in all three superinfected individuals prior to superinfection. In contrast, NAbs with a median IC50 titer of 1896 were detected as early as three months post-seroconversion in non-superinfected controls. Early plasma NAbs in all subjects showed limited but variable levels of heterologous neutralization breadth. Superinfected individuals also exhibited a trend toward lower levels of gp120- and V1V2-specific IgG binding antibodies but higher gp120-specific plasma IgA binding antibodies. CONCLUSIONS: These data suggest that the lack of development of IgG antibodies, as reflected in autologous NAbs as well as gp120 and V1V2 binding antibodies to the primary infection virus, combined with potentially competing, non-protective IgA antibodies, may increase susceptibility to superinfection in the context of settings where a single HIV-1 subtype predominates.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , HIV-1/imunologia , Superinfecção/virologia , Estudos de Casos e Controles , Linhagem Celular , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/virologia , HIV-1/genética , Humanos , Imunidade Humoral , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Filogeografia , Análise de Sequência de DNA
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...