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1.
PLoS Biol ; 20(3): e3001160, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35302985

RESUMEN

The spatial distribution of dengue and its vectors (spp. Aedes) may be the widest it has ever been, and projections suggest that climate change may allow the expansion to continue. However, less work has been done to understand how climate variability and change affects dengue in regions where the pathogen is already endemic. In these areas, the waxing and waning of immunity has a large impact on temporal dynamics of cases of dengue haemorrhagic fever. Here, we use 51 years of data across 72 provinces and characterise spatiotemporal patterns of dengue in Thailand, where dengue has caused almost 1.5 million cases over the last 30 years, and examine the roles played by temperature and dynamics of immunity in giving rise to those patterns. We find that timescales of multiannual oscillations in dengue vary in space and time and uncover an interesting spatial phenomenon: Thailand has experienced multiple, periodic synchronisation events. We show that although patterns in synchrony of dengue are similar to those observed in temperature, the relationship between the two is most consistent during synchronous periods, while during asynchronous periods, temperature plays a less prominent role. With simulations from temperature-driven models, we explore how dynamics of immunity interact with temperature to produce the observed patterns in synchrony. The simulations produced patterns in synchrony that were similar to observations, supporting an important role of immunity. We demonstrate that multiannual oscillations produced by immunity can lead to asynchronous dynamics and that synchrony in temperature can then synchronise these dengue dynamics. At higher mean temperatures, immune dynamics can be more predominant, and dengue dynamics more insensitive to multiannual fluctuations in temperature, suggesting that with rising mean temperatures, dengue dynamics may become increasingly asynchronous. These findings can help underpin predictions of disease patterns as global temperatures rise.


Asunto(s)
Dengue , Epidemias , Dengue/epidemiología , Humanos , Incidencia , Mosquitos Vectores , Temperatura , Tailandia/epidemiología
2.
Sex Transm Infect ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38964842

RESUMEN

OBJECTIVE: Voluntary medical male circumcision (MC) is a critical tool in combination HIV prevention programmes in Africa. Self-reported MC (SrMC) status is used in HIV epidemiological surveys to assess MC coverage but is subject to response bias with limited validation. This study evaluated the utility of SrMC status as a marker of MC as well as self-reported genital lesions for genital ulcer disease (GUD) among Ugandan men. METHODS: Male participants aged 18-49 years in the cross-sectional Sexually Transmitted Infection Prevalence study, conducted between May and October 2019, responded to a questionnaire capturing SrMC status and current genital ulcer symptoms followed by clinical assessment to verify MC and presence of GUD.Sensitivity, specificity, positive predictive value, negative predictive value and corresponding CIs (95% CI) for SrMC status and GUD were estimated. RESULTS: There were 853 male participants, of whom 470 (55.1%) self-reported being circumcised and 23 (2.7%) self-reported GUD (SrGUD). MC was clinically confirmed in 50.2% (n=428) of participants with sensitivity of SrMC status at 99% (95% CI: 98% to 100%) and specificity 89% (95% CI: 86% to 92%). Specificity of SrMC was lowest among persons living with HIV and viremic (>1000 copies/mL) at 72% (95% CI: 46% to 90%). 18 participants had clinically confirmed GUD, but only 12 SrGUD symptoms, corresponding to a sensitivity and specificity of 67% (95% CI: 41% to 87%) and 99% (95% CI: 98% to 99%), respectively. CONCLUSIONS: SrMC status is a robust proxy for clinically confirmed MC status and may reliably be used to assess MC coverage in this setting. Conversely, GUD symptoms were under-reported, which may impact effective syndromic management of sexually transmitted infections and warrants further examination.

3.
PLoS Pathog ; 14(7): e1007167, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30052678

RESUMEN

HIV-1 undergoes multiple rounds of error-prone replication between transmission events, resulting in diverse viral populations within and among individuals. In addition, the virus experiences different selective pressures at multiple levels: during the course of infection, at transmission, and among individuals. Disentangling how these evolutionary forces shape the evolution of the virus at the population scale is important for understanding pathogenesis, how drug- and immune-escape variants are likely to spread in populations, and the development of preventive vaccines. To address this, we deep-sequenced two regions of the HIV-1 genome (p24 and gp41) from 34 longitudinally-sampled untreated individuals from Rakai District in Uganda, infected with subtypes A, D, and inter-subtype recombinants. This dataset substantially increases the availability of HIV-1 sequence data that spans multiple years of untreated infection, in particular for different geographical regions and viral subtypes. In line with previous studies, we estimated an approximately five-fold faster rate of evolution at the within-host compared to the population scale for both synonymous and nonsynonymous substitutions, and for all subtypes. We determined the extent to which this mismatch in evolutionary rates can be explained by the evolution of the virus towards population-level consensus, or the transmission of viruses similar to those that establish infection within individuals. Our findings indicate that both processes are likely to be important.


Asunto(s)
Evolución Molecular , Infecciones por VIH/genética , Infecciones por VIH/virología , VIH-1/genética , Humanos , Uganda
4.
Transfusion ; 59(9): 2899-2907, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31222779

RESUMEN

BACKGROUND: Contemporary population-based data on characteristics associated with blood donation in the United States (U.S.) are limited. STUDY DESIGN AND METHODS: A cross-sectional analysis was performed among 28,739 persons aged 18 years and older who participated in the 2016 National Health Interview Survey, a household survey of the noninstitutionalized U.S. civilian population. Analyses were weighted and accounted for the complex survey design. Adjusted prevalence ratios (aPR) were estimated by multivariable log-binomial regression. RESULTS: The percentage of individuals reporting a past-year history of blood donation was 5.7% (95% confidence interval [CI], 5.3%-6.1%) and was highest in the youngest age group (18-24 years, 8.4%). A past-year history of blood donation was more common in males compared to females (6.3% vs. 5.1%; aPR, 1.12 [95% CI, 0.99-1.27]) and those born in the U.S. compared to individuals born outside the U.S. (6.4% vs. 2.4%; aPR, 1.92 [95% CI, 1.49-2.47]). The percentage of individuals with a past-year history of blood donation was significantly lower in blacks (3.9%; aPR, 0.60 [95% CI, 0.47-0.75]) and Hispanics (3.0%; aPR, 0.63 [95% CI, 0.48-0.83]) in comparison to whites (6.9%). Being a college graduate, being employed, being physically active, and never being a cigarette smoker were factors positively associated with blood donation. The percentage of individuals with a past-year history of blood donation varied by geographic census region, with prevalence being higher in the Midwest (7.3%) and South (6.0%) compared to the Northeast (4.7%) and West (4.4%). CONCLUSION: Continued differences in the blood donor population with reference to the U.S. population underscore the need to understand barriers or deterrents to blood donation. Evidence-based donor recruitment and related policies remain imperative to ensure that there is a sustainable blood supply.


Asunto(s)
Conducta/fisiología , Donantes de Sangre/psicología , Donantes de Sangre/estadística & datos numéricos , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Prevalencia , Factores Socioeconómicos , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Adulto Joven
5.
Transfusion ; 59(5): 1723-1733, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30779173

RESUMEN

BACKGROUND: Blood donation results in a loss of iron stores, which is particularly concerning for young female blood donors. This study examines the association of blood donation and iron deficiency among adolescent and adult females in the United States. STUDY DESIGN AND METHODS: A cross-sectional analysis was performed using data from the 1999-2010 National Health and Nutrition Examination Survey (NHANES). Females who reported their blood donation history in the preceding year and had serum ferritin (SF) measurements were included. Analyses were weighted and stratified by adolescents (16-19 years; n = 2419) and adults (20-49 years; n = 7228). Adjusted prevalence ratios (aPRs) were estimated by multivariable Poisson regression. Standard errors were estimated by Taylor series linearization. RESULTS: Geometric mean SF levels (ng/mL) were lower in blood donors compared to nondonors among adolescents (21.2 vs. 31.4; p < 0.001) and among adults (26.2 vs. 43.7; p < 0.001). The prevalence of absent iron stores (SF < 12 ng/mL) was higher in blood donors compared to nondonors among adolescents (22.6% vs. 12.2%; aPR = 2.03 [95% confidence interval (CI) = 1.45-2.85]) and among adults (18.3% vs. 9.8%; aPR = 2.06 [95% CI = 1.48-2.88]). Additionally, the prevalence of iron deficiency anemia (SF < 26 ng/mL and hemoglobin < 12.0 g/dL) was also higher in blood donors compared to nondonors among adolescents (9.5% vs. 6.1%; aPR = 2.10 [95% CI = 1.13-3.90]) and among adults (7.9% vs. 6.1%; aPR = 1.74 [95% CI = 1.06-2.85]). Similar results were observed in a sensitivity analysis restricted to adolescents aged 16 to 18 years. CONCLUSIONS: Blood donation is associated with iron deficiency among adolescent and adult females in the United States. These national data call for further development and implementation of blood donation practices aimed toward mitigating iron deficiency.


Asunto(s)
Anemia Ferropénica/sangre , Donantes de Sangre/estadística & datos numéricos , Ferritinas/sangre , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Adulto Joven
6.
Vox Sang ; 114(5): 517-522, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31056742

RESUMEN

BACKGROUND AND OBJECTIVES: Platelet dosing has been studied in adult oncology inpatients, but there is almost no published evidence to guide platelet dosing for adult outpatients. We evaluated transfusion indices after 1 unit and 2 unit apheresis platelet transfusions at our hospital to determine whether a benefit to 2-unit transfusions could be detected. MATERIALS AND METHODS: A retrospective chart review was conducted of all adult oncology patients who received an outpatient platelet transfusion over a 16-month period (July 2016-November 2017). Pre- and post-transfusion platelet count, and chronology of subsequent platelet transfusions were compared. RESULTS: A total of 8467 platelet transfusions were administered to 602 patients during the study period. 59·8% of patients (n = 360) were transfused interchangeably with one or two platelets throughout the study period. The primary study population were comprised of these patients. On average, a 2-unit platelet transfusions resulted in a higher immediate post-transfusion platelet count (43 vs. 37 x 103 /µl, P < 0·001) and a lower corrected count increment (9707 vs. 14 060, P < 0·001). Transfusion with 2 platelets did not increase the number of days between outpatient transfusions (median; 4 vs. 4, P = 0·959) or the platelet count at the time of next transfusion (11 vs. 11 x 103 /µl, P = 0·147). CONCLUSION: Among adult, oncology outpatients that were transfused interchangeably with one or two units of platelets, transfusion with two platelets did not offer a durable improvement in platelet count or impact the subsequent transfusion schedule.


Asunto(s)
Neoplasias , Pacientes Ambulatorios , Transfusión de Plaquetas/métodos , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Retrospectivos
7.
J Infect Dis ; 215(5): 772-780, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28011913

RESUMEN

Background: Limited data are available on human papillomavirus (HPV) infection among human immunodeficiency virus (HIV)-negative or HIV-positive couples followed longitudinally. Methods: Genital HPV was assessed in 725 concordant HIV-negative couples and 209 HIV-positive couples enrolled in a male circumcision trial in Rakai, Uganda, using the Roche Linear Array assay, which detects 37 HPV genotypes. Human papillomavirus prevalence and determinants of genotype-specific concordance were assessed at annual visits. Cumulative detection of HPV genotypes over 2 years was also assessed. Results: At enrollment, HPV infection was detected in 54% of HIV-negative women, 56% of HIV-negative men, and 93% of HIV-positive men and women. For HIV-negative couples, genotypic concordance was 30% at baseline (n = 219/725) and declined significantly with age (adjusted prevelance risk ratio [adjPRR] = 0.53; 95% confidence interval [CI] = 0.28-0.93 comparing women aged >40 years to those aged 15-19 years) and male circumcision (adjPRR = 0.60; 95% CI = 0.47-0.77) and increased among couples with recent intercourse (adjPRR = 1.26; 95% CI = 1.04-1.53). These associations were not seen in HIV-positive couples. Among couples with HPV results at all visits, ≥1 of the same genotypes were detected in both partners in 60% of HIV-negative couples and 96% of HIV-positive couples over 2 years. Conclusion: Human papillomavirus genotype-specific concordance is more common in HIV-positive couples, and irrespective of HIV status, the majority of couples exhibit HPV concordance over 2 years.


Asunto(s)
Seropositividad para VIH/epidemiología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Adolescente , Adulto , Circuncisión Masculina , Femenino , Estudios de Seguimiento , Genotipo , VIH/aislamiento & purificación , Seronegatividad para VIH , Seropositividad para VIH/complicaciones , Heterosexualidad , Humanos , Modelos Lineales , Masculino , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Prevalencia , Factores de Riesgo , Conducta Sexual , Parejas Sexuales , Factores Socioeconómicos , Uganda/epidemiología , Adulto Joven
8.
J Infect Dis ; 213(6): 948-56, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26597261

RESUMEN

BACKGROUND: The association between partner human papillomavirus (HPV) viral load and incident HPV detection in heterosexual couples is unknown. METHODS: HPV genotypes were detected in 632 human immunodeficiency virus (HIV)-negative couples followed for 2 years in a male circumcision trial in Rakai, Uganda, using the Roche HPV Linear Array. This assay detects 37 genotypes and provides a semiquantitative measure of viral load based on the intensity (graded 1-4) of the genotype-specific band; a band intensity of 1 indicates a low genotype-specific HPV load, whereas an intensity of 4 indicates a high load. Using Poisson regression with generalized estimating equations, we measured the association between partner's genotype-specific viral load and detection of that genotype in the HPV-discordant partner 1 year later. RESULTS: Incident detection of HPV genotypes was 10.6% among men (54 of 508 genotype-specific visit intervals) and 9.0% among women (55 of 611 genotype-specific visit intervals). Use of male partners with a baseline genotype-specific band intensity of 1 as a reference yielded adjusted relative risks (aRRs) of 1.14 (95% confidence interval [CI], .58-2.27]) for incident detection of that genotype among women whose male partner had a baseline band intensity of 2, 1.75 (95% CI, .97-3.17) among those whose partner had an intensity of 3, and 2.52 (95% CI, 1.40-4.54) among those whose partner had an intensity of 4. Use of female partners with a baseline genotype-specific band intensity of 1 as a reference yielded an aRR of 2.83 (95% CI, 1.50-5.33) for incident detection of that genotype among men whose female partner had a baseline band intensity of 4. These associations were similar for high-risk and low-risk genotypes. Male circumcision also was associated with significant reductions in incident HPV detection in men (aRR, 0.53 [95% CI, .30-.95]) and women (aRR, 0.42 [95% CI, .23-.76]). CONCLUSIONS: In heterosexual couples, the genotype-specific HPV load in one partner is associated with the risk of new detection of that genotype in the other partner. Interventions that reduce the HPV load may reduce the incidence of HPV transmission.


Asunto(s)
Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Parejas Sexuales , Carga Viral , Adulto , Circuncisión Masculina , Femenino , Genotipo , Humanos , Masculino , Papillomaviridae/clasificación , Infecciones por Papillomavirus/epidemiología , Factores de Riesgo , Uganda/epidemiología , Adulto Joven
9.
J Infect Dis ; 212(10): 1613-7, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25943201

RESUMEN

A prospective observational study of 176 men coinfected with human immunodeficiency virus and herpes simplex virus type 2 (HSV-2) was conducted to assess whether their sexual partners may be at an increased risk of HSV-2 from male circumcision (MC) wounds. Preoperative and weekly penile lavage samples were tested for penile HSV-2 shedding. Prevalence risk ratios (PRRs) were estimated using Poisson regression. Detectable penile HSV-2 shedding was present in 9.7% of men (17 of 176) before MC, compared with 12.9% (22 of 170) at 1 week (PRR, 1.33; 95% confidence interval [CI], .74-2.38) and 14.8% (23 of 155) at 2 weeks (PRR, 1.50; 95% CI, .86-2.62) after MC. HSV-2 shedding was lower among men with healed MC wounds (adjusted PRR, 0.62; 95% CI, .35-1.08). Men undergoing MC should be counseled on sexual abstinence and condom use.


Asunto(s)
Circuncisión Masculina , Herpes Genital/virología , Herpesvirus Humano 2/aislamiento & purificación , Esparcimiento de Virus , Heridas y Lesiones/virología , Adolescente , Adulto , Transmisión de Enfermedad Infecciosa/prevención & control , Infecciones por VIH/complicaciones , Herpes Genital/epidemiología , Humanos , Masculino , Prevalencia , Estudios Prospectivos , Medición de Riesgo , Uganda , Adulto Joven
10.
J Infect Dis ; 212(6): 899-903, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25743428

RESUMEN

Vaginal shedding of cytomegalovirus (CMV) DNA was determined longitudinally among 96 women coinfected with human immunodeficiency virus (HIV), herpes simplex virus 2, and CMV starting antiretroviral therapy (ART) during a placebo-controlled trial of HSV-2 suppression with acyclovir in Rakai, Uganda. Vaginal CMV was detected in 75 of 96 women (78.0%) and 379 of 1080 individual visits (35.1%). ART status, higher HIV RNA viral load before ART initiation, and younger age were significantly associated with increased frequency of CMV shedding (P < .01). Compared to pre-ART, CMV shedding peaked from month 2 to month 4 after ART initiation, suggesting possible immune reconstitution inflammatory syndrome. Further studies need to determine the clinical significance of asymptomatic CMV shedding.


Asunto(s)
Aciclovir/uso terapéutico , Antirretrovirales/uso terapéutico , Infecciones por Citomegalovirus/tratamiento farmacológico , Citomegalovirus/fisiología , Vagina/virología , Esparcimiento de Virus/efectos de los fármacos , Aciclovir/administración & dosificación , Adulto , Recuento de Linfocito CD4 , Coinfección , Infecciones por Citomegalovirus/epidemiología , Método Doble Ciego , Femenino , Infecciones por VIH/tratamiento farmacológico , Herpes Genital/tratamiento farmacológico , Herpesvirus Humano 2 , Humanos , Estudios Longitudinales , Uganda/epidemiología
11.
PLoS Med ; 12(4): e1001820, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25919012

RESUMEN

BACKGROUND: A randomized trial of voluntary medical male circumcision (MC) of HIV-infected men reported increased HIV transmission to female partners among men who resumed sexual intercourse prior to wound healing. We conducted a prospective observational study to assess penile HIV shedding after MC. METHODS AND FINDINGS: HIV shedding was evaluated among 223 HIV-infected men (183 self-reported not receiving antiretroviral therapy [ART], 11 self-reported receiving ART and had a detectable plasma viral load [VL], and 29 self-reported receiving ART and had an undetectable plasma VL [<400 copies/ml]) in Rakai, Uganda, between June 2009 and April 2012. Preoperative and weekly penile lavages collected for 6 wk and then at 12 wk were tested for HIV shedding and VL using a real-time quantitative PCR assay. Unadjusted prevalence risk ratios (PRRs) and adjusted PRRs (adjPRRs) of HIV shedding were estimated using modified Poisson regression with robust variance. HIV shedding was detected in 9.3% (17/183) of men not on ART prior to surgery and 39.3% (72/183) of these men during the entire study. Relative to baseline, the proportion shedding was significantly increased after MC at 1 wk (PRR = 1.87, 95% CI = 1.12-3.14, p = 0.012), 2 wk (PRR = 3.16, 95% CI = 1.94-5.13, p < 0.001), and 3 wk (PRR = 1.98, 95% CI = 1.19-3.28, p = 0.008) after MC. However, compared to baseline, HIV shedding was decreased by 6 wk after MC (PRR = 0.27, 95% CI = 0.09-0.83, p = 0.023) and remained suppressed at 12 wk after MC (PRR = 0.19, 95% CI = 0.06-0.64, p = 0.008). Detectable HIV shedding from MC wounds occurred in more study visits among men with an HIV plasma VL > 50,000 copies/ml than among those with an HIV plasma VL < 400 copies/ml (adjPRR = 10.3, 95% CI = 4.25-24.90, p < 0.001). Detectable HIV shedding was less common in visits from men with healed MC wounds compared to visits from men without healed wounds (adjPRR = 0.12, 95% CI = 0.07-0.23, p < 0.001) and in visits from men on ART with undetectable plasma VL compared to men not on ART (PRR = 0.15, 95% CI = 0.05-0.43, p = 0.001). Among men with detectable penile HIV shedding, the median log10 HIV copies/milliliter of lavage fluid was significantly lower in men with ART-induced undetectable plasma VL (1.93, interquartile range [IQR] = 1.83-2.14) than in men not on ART (2.63, IQR = 2.28-3.22, p < 0.001). Limitations of this observational study include significant differences in baseline covariates, lack of confirmed receipt of ART for individuals who reported ART use, and lack of information on potential ART initiation during follow-up for those who were not on ART at enrollment. CONCLUSION: Penile HIV shedding is significantly reduced after healing of MC wounds. Lower plasma VL is associated with decreased frequency and quantity of HIV shedding from MC wounds. Starting ART prior to MC should be considered to reduce male-to-female HIV transmission risk. Research is needed to assess the time on ART required to decrease shedding, and the acceptability and feasibility of initiating ART at the time of MC.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/transmisión , VIH-1 , Pene , Carga Viral , Infección de Heridas/virología , Heridas y Lesiones/virología , Adulto , Antivirales/uso terapéutico , Femenino , Infecciones por VIH/etiología , Infecciones por VIH/virología , Humanos , Masculino , Pene/cirugía , Pene/virología , Prevalencia , Estudios Prospectivos , Autoinforme , Uganda/epidemiología , Infección de Heridas/complicaciones
12.
J Infect Dis ; 209(1): 66-73, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23922373

RESUMEN

BACKGROUND: Determinants of intersubtype differences in human immunodeficiency virus type 1 (HIV-1) clinical disease progression remain unknown. METHODS: HIV-1 subtype was independently determined for 5 separate genomic regions in 396 HIV-1 seroconverters from Rakai, Uganda, using a multiregion hybridization assay. Replication capacities (RC) in samples from a subset of 145 of these subjects were determined. HIV-1 genomic regions and pol RC were examined for association with disease progression. Amino acid polymorphisms were examined for association with pol RC. RESULTS: In multivariate analyses, the hazard for progression to the composite end point (defined as a CD4(+) T-cell count <250 cells/mm(3), antiretroviral therapy initiation, or death) among patients with subtype D pol infection was 2.4 times the hazard for those infected with subtype A pol infection (P = .001). Compared with subtype A pol (the reference group), the hazard for progression to the composite end point for subtype D pol infection with a pol RC >67% (ie, the median pol RC) was significantly greater (HR, 4.6; 95% confidence interval [CI], 1.9-11.0; P = .001), whereas the hazard for progression to the composite end point for subtype D pol infection with a pol RC ≤67% was not significantly different (HR, 2.2; 95% CI, 1.0-4.9; P = .051). Amino acid substitutions at protease positions 62 and 64 and at reverse transcriptase position 272 were associated with significant differences in pol RC. CONCLUSIONS: HIV-1 pol gene intersubtype and RC differences are associated with disease progression and may be influenced by amino acid polymorphisms.


Asunto(s)
Genes pol , Infecciones por VIH/virología , VIH-1/fisiología , Replicación Viral/genética , Adolescente , Adulto , Sustitución de Aminoácidos , Progresión de la Enfermedad , Femenino , VIH-1/enzimología , VIH-1/genética , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Uganda , Carga Viral
13.
PLoS Med ; 11(3): e1001610, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24595023

RESUMEN

BACKGROUND: It is often assumed that local sexual networks play a dominant role in HIV spread in sub-Saharan Africa. The aim of this study was to determine the extent to which continued HIV transmission in rural communities--home to two-thirds of the African population--is driven by intra-community sexual networks versus viral introductions from outside of communities. METHODS AND FINDINGS: We analyzed the spatial dynamics of HIV transmission in rural Rakai District, Uganda, using data from a cohort of 14,594 individuals within 46 communities. We applied spatial clustering statistics, viral phylogenetics, and probabilistic transmission models to quantify the relative contribution of viral introductions into communities versus community- and household-based transmission to HIV incidence. Individuals living in households with HIV-incident (n = 189) or HIV-prevalent (n = 1,597) persons were 3.2 (95% CI: 2.7-3.7) times more likely to be HIV infected themselves compared to the population in general, but spatial clustering outside of households was relatively weak and was confined to distances <500 m. Phylogenetic analyses of gag and env genes suggest that chains of transmission frequently cross community boundaries. A total of 95 phylogenetic clusters were identified, of which 44% (42/95) were two individuals sharing a household. Among the remaining clusters, 72% (38/53) crossed community boundaries. Using the locations of self-reported sexual partners, we estimate that 39% (95% CI: 34%-42%) of new viral transmissions occur within stable household partnerships, and that among those infected by extra-household sexual partners, 62% (95% CI: 55%-70%) are infected by sexual partners from outside their community. These results rely on the representativeness of the sample and the quality of self-reported partnership data and may not reflect HIV transmission patterns outside of Rakai. CONCLUSIONS: Our findings suggest that HIV introductions into communities are common and account for a significant proportion of new HIV infections acquired outside of households in rural Uganda, though the extent to which this is true elsewhere in Africa remains unknown. Our results also suggest that HIV prevention efforts should be implemented at spatial scales broader than the community and should target key populations likely responsible for introductions into communities.


Asunto(s)
Epidemias , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , VIH-1/fisiología , Filogenia , Población Rural , Adolescente , Adulto , Femenino , Infecciones por VIH/virología , Seropositividad para VIH/epidemiología , Seropositividad para VIH/transmisión , Seropositividad para VIH/virología , VIH-1/genética , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos Teóricos , Prevalencia , Conducta Sexual , Uganda/epidemiología , Adulto Joven
14.
Sex Transm Infect ; 90(2): 150-4, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24259189

RESUMEN

OBJECTIVE: Previous randomised trial data have demonstrated that male circumcision reduces Mycoplasma genitalium prevalence in men. We assessed whether male circumcision also reduces M genitalium infection in female partners of circumcised men. METHODS: HIV-negative men were enrolled and randomised to either male circumcision or control. Female partners of male trial participants from the intervention (n=437) and control (n=394) arms provided interview information and self-collected vaginal swabs that were tested for M genitalium by APTIMA transcription-mediated amplification-based assay. Prevalence risk ratios (PRR) and 95% CI of M genitalium prevalence in intervention versus control group were estimated using Poisson regression. Analysis was by intention-to-treat. An as-treated analysis was conducted to account for study-group crossovers. RESULTS: Male and female partner enrolment sociodemographic characteristics, sexual behaviours, and symptoms of sexually transmitted infections were similar between study arms. Female M genitalium prevalence at year 2 was 3.2% (14/437) in the intervention arm and 3.6% (14/394) in the control arm (PRR=0.90, 95% CI 0.43 to 1.89, p=0.78). In an as-treated analysis, the prevalence of M genitalium was 3.4% in female partners of circumcised men and 3.3% in female partners of uncircumcised men (PRR=1.01, 95% CI 0.48 to 2.12, p=0.97). CONCLUSIONS: Contrary to findings in men, male circumcision did not affect M genitalium infection in female partners.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/epidemiología , Infecciones por Mycoplasma/epidemiología , Mycoplasma genitalium/aislamiento & purificación , Parejas Sexuales , Vagina/microbiología , Adolescente , Adulto , Femenino , Infecciones por VIH/prevención & control , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Infecciones por Mycoplasma/microbiología , Infecciones por Mycoplasma/prevención & control , Distribución de Poisson , Factores de Riesgo , Conducta Sexual , Uganda/epidemiología
15.
Sex Transm Infect ; 90(4): 337-43, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24482488

RESUMEN

OBJECTIVES: High-risk human papillomavirus (HR-HPV) viral load is associated with HR-HPV transmission and HR-HPV persistence in women. It is unknown whether HR-HPV viral load is associated with persistence in HIV-negative or HIV-positive men. METHODS: HR-HPV viral load and persistence were evaluated among 703 HIV-negative and 233 HIV-positive heterosexual men who participated in a male circumcision trial in Rakai, Uganda. Penile swabs were tested at baseline and 6, 12 and 24 months for HR-HPV using the Roche HPV Linear Array, which provides a semiquantitative measure of HPV shedding by hybridisation band intensity (graded: 1-4). Prevalence risk ratios (PRR) were used to estimate the association between HR-HPV viral load and persistent detection of HR-HPV. RESULTS: HR-HPV genotypes with high viral load (grade:3-4) at baseline were more likely to persist than HR-HPV genotypes with low viral load (grade: 1-2) among HIV-negative men (month 6: adjPRR=1.83, 95% CI 1.32 to 2.52; month 12: adjPRR=2.01, 95% CI 1.42 to 3.11), and HIV-positive men (month 6: adjPRR=1.33, 95% CI 1.06 to 1.67; month 12: adjPRR=1.73, 95% CI 1.18 to 2.54). Long-term persistence of HR-HPV was more frequent among HIV-positive men compared with HIV-negative men (month 24: adjPRR=2.27, 95% CI 1.47 to 3.51). Persistence of newly detected HR-HPV at the 6-month and 12-month visits with high viral load were also more likely to persist to 24 months than HR-HPV with low viral load among HIV-negative men (adjPRR=1.67, 95% CI 0.88 to 3.16). CONCLUSIONS: HR-HPV genotypes with high viral load are more likely to persist among HIV-negative and HIV-positive men, though persistence was more common among HIV-positive men overall. The results may explain the association between high HR-HPV viral load and HR-HPV transmission.


Asunto(s)
Infecciones por VIH/complicaciones , Heterosexualidad , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Pene/virología , Carga Viral , Adolescente , Adulto , Estudios de Casos y Controles , Genotipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Papillomavirus Humano 31/genética , Humanos , Masculino , Papillomaviridae/clasificación , Infecciones por Papillomavirus/complicaciones , Conducta Sexual , Uganda , Adulto Joven
16.
J Infect Dis ; 207(11): 1713-22, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23345339

RESUMEN

BACKGROUND: The association between human papillomavirus (HPV) infection and the risk of human immunodeficiency virus (HIV) seroconversion is unclear, and the genital cellular immunology has not been evaluated. METHODS: A case-control analysis nested within a male circumcision trial was conducted. Cases consisted of 44 male HIV seroconverters, and controls were 787 males who were persistently negative for HIV. The Roche HPV Linear Array Genotype Test detected high-risk HPV (HR-HPV) and low-risk HPV (LR-HPV) genotypes. Generalized estimating equations logistic regression was used to estimate adjusted odds ratios (aORs) of HIV seroconversion. In addition, densities of CD1a(+) dendritic cells, CD4(+) T cells, and CD8(+) T cells were measured using immunohistochemistry analysis in foreskins of 79 males randomly selected from participants in the circumcision trial. RESULTS: HR-HPV or LR-HPV acquisition was not significantly associated with HIV seroconversion, after adjustment for sexual behaviors. However, HR-HPV and LR-HPV clearance was significantly associated with HIV seroconversion (aOR, 3.25 [95% confidence interval {CI}, 1.11-9.55] and 3.18 [95% CI, 1.14-8.90], respectively). The odds of HIV seroconversion increased with increasing number of HPV genotypes cleared (P < .001, by the test for trend). The median CD1a(+) dendritic cell density in the foreskin epidermis was significantly higher among males who cleared HPV (72.0 cells/mm(2) [interquartile range {IQR}, 29.4-138.3 cells/mm(2)]), compared with males who were persistently negative for HPV (32.1 cells/mm(2) [IQR, 3.1-96.2 cells/mm(2)]; P = .047), and increased progressively with the number of HPV genotypes cleared (P = .05). CONCLUSIONS: HPV clearance was associated with subsequent HIV seroconversion and also with increased epidermal dendritic cell density, which potentially mediates HIV seroconversion.


Asunto(s)
Células Dendríticas/inmunología , Prepucio/inmunología , Prepucio/virología , Infecciones por VIH/complicaciones , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Adolescente , Adulto , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Estudios de Casos y Controles , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/patología , Seropositividad para VIH , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Adulto Joven
17.
J Infect Dis ; 208(5): 839-46, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23812240

RESUMEN

BACKGROUND: The association between initiation of antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection and possible herpes simplex virus type 2 (HSV-2) shedding and genital ulcer disease (GUD) has not been evaluated. METHODS: GUD and vaginal HSV-2 shedding were evaluated among women coinfected with HIV and HSV-2 (n = 440 for GUD and n = 96 for HSV-2 shedding) who began ART while enrolled in a placebo-controlled trial of HSV-2 suppression with acyclovir in Rakai, Uganda. Monthly vaginal swabs were tested for HSV-2 shedding, using a real-time quantitative polymerase chain reaction assay. Prevalence risk ratios (PRRs) of GUD were estimated using log binomial regression. Random effects logistic regression was used to estimate odds ratios (ORs) of HSV-2 shedding. RESULTS: Compared with pre-ART values, GUD prevalence increased significantly within the first 3 months after ART initiation (adjusted PRR, 1.94; 95% confidence interval [CI], 1.04-3.62) and returned to baseline after 6 months of ART (adjusted PRR, 0.80; 95% CI, .35-1.80). Detection of HSV-2 shedding was highest in the first 3 months after ART initiation (adjusted OR, 2.58; 95% CI, 1.48-4.49). HSV-2 shedding was significantly less common among women receiving acyclovir (adjusted OR, 0.13; 95% CI, .04-.41). CONCLUSIONS: The prevalence of HSV-2 shedding and GUD increased significantly after ART initiation, possibly because of immune reconstitution inflammatory syndrome. Acyclovir significantly reduced both GUD and HSV-2 shedding and should be considered to mitigate these effects following ART initiation.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Herpes Genital/complicaciones , Herpes Genital/virología , Herpesvirus Humano 2/efectos de los fármacos , Activación Viral , Aciclovir/administración & dosificación , Adulto , Antirretrovirales/administración & dosificación , Coinfección/tratamiento farmacológico , Coinfección/virología , Femenino , Herpesvirus Humano 2/fisiología , Humanos , Masculino , Persona de Mediana Edad , Placebos/administración & dosificación , Uganda , Vagina/virología , Esparcimiento de Virus , Adulto Joven
18.
Int J Cancer ; 133(5): 1247-52, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23400966

RESUMEN

Male circumcision (MC) reduces high-risk human papillomavirus (HR-HPV) infection in female partners. We evaluated the intensity of HR-HPV viral DNA load in HIV-negative, HR-HPV-positive female partners of circumcised and uncircumcised men. HIV-negative men and their female partners were enrolled in randomized trials of MC in Rakai, Uganda. Vaginal swabs were tested for HR-HPV genotypes by Roche HPV Linear Array which provides a semi-quantitative measure of HPV DNA by the intensity of genotype-specific bands (graded:1-4). We assessed the effects of MC on female HR-HPV DNA load by comparing high intensity linear array bands (3-4) to low intensity bands (1-2) using an intention-to-treat analysis. Prevalence risk ratios (PRR) of high intensity bands in partners of intervention versus control arm men were estimated using log-binomial regression with robust variance. The trial included 335 women with male partners in the intervention arm and 340 in the control arm. At enrollment, the frequency of HR-HPV high intensity linear array bands was similar in both study arms. At 24 months follow-up, the prevalence of high intensity bands among women with detectable HR-HPV was significantly lower in partners of intervention arm (42.7%) than control arm men (55.1%, PRR = 0.78, 95% CI 0.65-0.94, p = 0.02), primarily among incident HR-HPV infections (PRR = 0.66, 95% CI 0.50-0.87, p = 0.003), but not persistent infections (PRR = 1.02, 95% CI 0.83-1.24). Genotypes with high HR-HPV band intensity were more likely to persist (adjHR = 1.27 95% CI 1.07-1.50), irrespective of male partner circumcision status. MC reduces HR-HPV DNA load in newly infected female partners.


Asunto(s)
Circuncisión Masculina , Papillomaviridae/aislamiento & purificación , Carga Viral , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Uganda
19.
Sex Transm Infect ; 89(2): 122-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22628661

RESUMEN

OBJECTIVES: Human papillomavirus (HPV) infection causes genital warts, penile cancer and cervical cancer. Africa has one of the highest rates of penile and cervical cancers, but there are little data on high-risk human papillomavirus (HR-HPV) prevalence in heterosexual men. Knowledge of HR-HPV prevalence, risk factors and genotype distribution among heterosexual men is important to establish risk-reduction prevention strategies. METHODS: 1578 uncircumcised men aged 15-49 years who enrolled in male circumcision trials in Rakai, Uganda, were evaluated for HR-HPV from swabs of the coronal sulcus/glans using Roche HPV Linear Array. Adjusted prevalence risk ratios (adjPRRs) were estimated using modified Poisson multivariable regression. RESULTS: HPV prevalence (either high risk or low risk) was 90.7% (382/421) among HIV-positive men and 60.9% (596/978) among HIV-negative men (PRR 1.49, 95% CI 1.40 to 1.58). HIV-positive men had a significantly higher risk of infection with three or more HR-HPV genotypes (PRR=5.76, 95% CI 4.27 to 7.79). Among HIV-positive men, high-risk sexual behaviours were not associated with increased HR-HPV prevalence. Among HIV-negative men, HR-HPV prevalence was associated with self-reported genital warts (adjPRR 1.57, 95% CI 1.07 to 2.31). Among all men (both HIV negative and HIV positive), HR-HPV prevalence was associated with more than 10 lifetime sexual partners (adjPRR 1.30, 95% CI 1.01 to 1.66), consistent condom use (adjPRR 1.31, 95% CI 1.08 to 1.60) and HIV infection (adjPRR 1.80, 95% CI 1.60 to 2.02). HR-HPV prevalence was lower among men who reported no sexual partners during the past year (adjPRR 0.47, 95% CI 0.23 to 0.94). CONCLUSION: The burden of HR-HPV infection is high among heterosexual men in sub-Saharan Africa and most pronounced among the HIV-infected individuals.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Heterosexualidad , Papillomaviridae/patogenicidad , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Adolescente , Adulto , Coinfección/epidemiología , Coinfección/virología , Humanos , Masculino , Persona de Mediana Edad , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Prevalencia , Uganda/epidemiología , Adulto Joven
20.
J Infect Dis ; 206(2): 267-74, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-22675216

RESUMEN

BACKGROUND: Human immunodeficiency virus (HIV) superinfection has been documented in high-risk individuals; however, the rate of superinfection among HIV-infected individuals within a general population remains unknown. METHODS: A novel next-generation ultra-deep sequencing technique was utilized to determine the rate of HIV superinfection in a heterosexual population by examining two regions of the viral genome in longitudinal samples from recent HIV seroconverters (n=149) in Rakai District, Uganda. RESULTS: The rate of superinfection was 1.44 per 100 person years (PYs) (95% confidence interval [CI], .4-2.5) and consisted of both inter- and intrasubtype superinfections. This was compared to primary HIV incidence in 20 220 initially HIV-negative individuals in the general population in Rakai (1.15 per 100 PYs; 95% CI, 1.1-1.2; P= .26). Propensity score matching (PS) was used to control for differences in sociodemographic and behavioral characteristics between the HIV-positive individuals at risk for superinfection and the HIV-negative population at baseline and follow-up. After PS matching, the estimated rate of primary incidence was 3.28 per 100 PYs (95% CI, 2.0-5.3; P = .07) controlling for baseline differences and 2.51 per 100 PYs (95% CI, 1.5-4.3; P = .24) controlling for follow-up differences. CONCLUSIONS: This suggests that the rate of HIV superinfection in a general population is substantial, which could have a significant impact on future public health and HIV vaccine strategies.


Asunto(s)
Infecciones por VIH/epidemiología , Sobreinfección/epidemiología , Sobreinfección/virología , Adolescente , Adulto , Estudios de Cohortes , Femenino , Infecciones por VIH/patología , Infecciones por VIH/virología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Uganda/epidemiología , Adulto Joven
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