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1.
Euro Surveill ; 23(47)2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30482265

RESUMEN

BackgroundMonitoring hepatitis C virus (HCV) incidence is important for assessing intervention impact. Longitudinal studies of people who inject drugs (PWID), using repeated biological tests, are costly; alternatively, incidence can be estimated using biological markers of recent infection in cross-sectional studies.AimWe aimed to compare incidence estimates obtained from two different biological markers of recent infection in a cross-sectional study to inform monitoring approaches for HCV elimination strategies.MethodSamples from an unlinked anonymous bio-behavioural survey of PWID were tested for two recent infection markers: HCV RNA with anti-HCV negative ('RNA') and low-avidity anti-HCV with HCV RNA present ('avidity'). These two markers were used separately and in combination to estimate HCV incidence.ResultsBetween 2011 and 2013, 2,816 anti-HIV-negative PWID (25% female) who had injected during the preceding year were either HCV-negative or had one of the two markers of recent infection: 57 (2.0%) had the RNA marker and 90 (3.2%) the avidity marker. The two markers had similar distributions of risk and demographic factors. Pooled estimated incidence was 12.3 per 100 person-years (pyrs) (95% credible interval: 8.8-17.0) and not significantly different to avidity-only (p = 0.865) and RNA-only (p = 0.691) estimates. However, the RNA marker is limited by its short duration before anti-HCV seroconversion and the avidity marker by uncertainty around its duration.ConclusionBoth markers have utility in monitoring HCV incidence among PWID. When HCV transmission is high, one marker may provide an accurate estimate of incidence; when it is low or decreasing, a combination may be required.


Asunto(s)
Biomarcadores/sangre , Hepacivirus/inmunología , Hepatitis C/prevención & control , ARN Viral/sangre , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/virología , Adulto , Estudios Transversales , Inglaterra/epidemiología , Femenino , Hepatitis C/sangre , Hepatitis C/epidemiología , Hepatitis C/transmisión , Anticuerpos contra la Hepatitis C/sangre , Anticuerpos contra la Hepatitis C/inmunología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Irlanda del Norte/epidemiología , Prevalencia , Abuso de Sustancias por Vía Intravenosa/epidemiología , Gales/epidemiología
2.
BMC Infect Dis ; 17(Suppl 1): 705, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29143611

RESUMEN

BACKGROUND: Initial serological testing for chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection is conducted using either rapid diagnostic tests (RDT) or laboratory-based enzyme immunoassays (EIA)s for detection of hepatitis B surface antigen (HBsAg) or antibodies to HCV (anti-HCV), typically on serum or plasma specimens and, for certain RDTs, capillary whole blood. WHO recommends the use of standardized testing strategies - defined as a sequence of one or more assays to maximize testing accuracy while simplifying the testing process and ideally minimizing cost. Our objective was to examine the diagnostic outcomes of a one- versus two-assay serological testing strategy. These data were used to inform recommendations in the 2017 WHO Guidelines on hepatitis B and C testing. METHODS: Few published studies have compared diagnostic outcomes for one-assay versus two-assay serological testing strategies for HBsAg and anti-HCV. Therefore, the principles of Bayesian statistics were used to conduct a modelling exercise to examine the outcomes of a one-assay versus two-assay testing strategy when applied to a hypothetical population of 10,000 individuals. The resulting model examined the diagnostic outcomes (true and false positive diagnoses; true and false negative diagnoses; positive and negative predictive values as a function of prevalence; and total tests required) for both one-assay and two-assay testing strategies. The performance characteristics assumed for assays used within the testing strategies were informed by WHO prequalification assessment findings and systematic reviews for diagnostic accuracy studies. Each of the presumptive testing strategies (one-assay or two-assay) was modelled at varying prevalences of HBsAg (10%, 2% and 0.4%) and of anti-HCV (40%, 10%, 2% and 0.4%), aimed at representing the range of testing populations typically encountered in WHO Member States. When the two-assay testing strategy was considered, the model assumed the independence of the two assays. RESULTS: Modeling demonstrated that applying a single assay (HBsAg or anti-HCV), even with high specificity (99%), may result in considerable numbers of false positive diagnoses and low positive predictive values (PPV), particularly in lower prevalence settings. Even at very low prevalences shifting to a two-assay testing strategy would result in a PPV approaching 1.0. When test sensitivity is high (>99%) false negative reactions are rare at all but the highest prevalences; but a two-test strategy might yield more false negative diagnoses. The order in which the tests are used has no impact on the overall accuracy of a two-assay strategy though it may impact the total number of tests needed to complete the diagnostic strategy, incurring added cost and complexity. HBsAg assays may have a low sensitivity (<90%), and result in large numbers of false negative diagnoses, particularly in high prevalence settings, which would be exacerbated in the two-assay testing strategy. In contrast, most anti-HCV assays have high sensitivity and lead to fewer false negative results, both in the one-assay and two-assay testing strategies. At prevalences ≤2% the number of tests needed using a second assay was nearly always small, at <300 per 10,000 individuals tested, making sustainability of a second assay uncertain in such a setting. CONCLUSIONS: A key public health objective of an effective testing strategy is to identify all individuals who would benefit from treatment. Therefore, a strategy that prioritizes a high NPV (minimal false negatives) may be acceptable even if the PPV is suboptimal (some false positives) as the implementation of such a public health programme must also take account of other factors such as costs, feasibility, impact on testing uptake and linkage to care, and consequences of a false-positive test. This rationale informed the development of the WHO Viral Hepatitis Testing Guidelines, with a conditional recommendation for a one-assay serological testing strategy in most testing settings and populations (≥0.4% prevalence in population tested). A one-test strategy results in few failures to diagnose infection and, although it is associated under most assumptions with a sub-optimal PPV, benefits include greater simplicity, easier implementation, lower costs and better feasibility, uptake and linkage to care. Furthermore, prior to antiviral therapy all those diagnosed either HBsAg or anti-HCV positive will require confirmation of viræmia, preventing unnecessary treatment of those who may be false positive on serology. For HBsAg, in low-prevalence settings (≤0.4%), a second recommendation was made to consider a two-assay testing strategy, using a confirmatory neutralization step or a second different HBsAg assay.


Asunto(s)
Hepatitis B/diagnóstico , Hepatitis C/diagnóstico , Pruebas Serológicas/métodos , Teorema de Bayes , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Anticuerpos contra la Hepatitis C/sangre , Humanos , Técnicas para Inmunoenzimas , Modelos Teóricos , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad
3.
BMC Cancer ; 14: 384, 2014 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-24885011

RESUMEN

BACKGROUND: Persistent infection with oncogenic Human Papillomavirus (HPV) is associated with the development of cervical cancer with each genotype differing in their relative contribution to the prevalence of cervical disease. HPV DNA testing offers improved sensitivity over cytology testing alone but is accompanied by a generally low specificity. Potential molecular markers of cervical disease include type-specific viral load (VL), integration of HPV DNA into the host genome and methylation of the HPV genome. The aim of this study was to evaluate the relationship between HPV type-specific viral load, integration and methylation status and cervical disease stage in samples harboring HPV16, HPV18, HPV31 or HPV45. METHODS: Samples singly infected with HPV16 (n=226), HPV18 (n=32), HPV31 (n=75) or HPV45 (n=29) were selected from a cohort of 4,719 women attending cervical screening in England. Viral load and integration status were determined by real-time PCR while 3'L1-URR methylation status was determined by pyrosequencing or sequencing of multiple clones derived from each sample. RESULTS: Viral load could differentiate between normal and abnormal cytology with a sensitivity of 75% and a specificity of 80% (odds ratio [OR] 12.4, 95% CI 6.2-26.1; p<0.001) with some variation between genotypes. Viral integration was poorly associated with cervical disease. Few samples had fully integrated genomes and these could be found throughout the course of disease. Overall, integration status could distinguish between normal and abnormal cytology with a sensitivity of 72% and a specificity of 50% (OR 2.6, 95% CI 1.0-6.8; p=0.054). Methylation levels were able to differentiate normal and low grade cytology from high grade cytology with a sensitivity of 64% and a specificity of 82% (OR 8.2, 95% CI 3.8-18.0; p<0.001). However, methylation varied widely between genotypes with HPV18 and HPV45 exhibiting a broader degree and higher magnitude of methylated CpG sites than HPV16 and HPV31. CONCLUSIONS: This study lends support for HPV viral load and CpG methylation status, but not integration status, to be considered as potential biomarkers of cervical disease.


Asunto(s)
Metilación de ADN/genética , Neoplasias del Cuello Uterino/genética , Carga Viral/genética , Integración Viral/genética , Adulto , Islas de CpG/genética , Femenino , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidad , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/patogenicidad , Humanos , Persona de Mediana Edad , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
4.
Sex Transm Infect ; 88(6): 456-61, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22628667

RESUMEN

OBJECTIVES: In the UK, although transmission of HIV among injecting drug user (IDUs) has been limited since the 1980s, IDUs and men who have sex with men (MSM) have higher HIV and hepatitis C virus (HCV) prevalences than the general population. MSM who are also IDUs (MSM-IDUs) may therefore have a higher risk of infection than male IDUs who only have sex with women. METHODS: Analysis of data from a national survey of IDUs attending services (England, Wales and Northern Ireland) between 1998 and 2007, which collected demographic and behavioural data and oral fluid samples for HIV and HCV antibody testing. RESULTS: Of the 8671 men who reported injecting drugs and having sex during the preceding year, 96% (8354) were men who only had sex with women (MSW). MSM-IDUs and MSW-IDUs had similar age and number of years of injecting. MSM-IDUs had a higher prevalence of HIV (adjusted OR=4.08, 95% CI 1.9 to 8.5) and of HCV (adjusted OR =1.34, 95% CI 1.1 to 1.8) and were about four times (adjusted OR =3.78, 95% CI 2.9 to 4.9) more likely to have unprotected sex with multiple partners. Among those who injected in the 4 weeks prior to participation, the MSM-IDUs had a higher level of needle/syringe sharing (adjusted OR =1.72, 95% CI 1.3 to 2.2). DISCUSSION: MSM-IDUs have a fourfold higher risk of HIV; HCV prevalence in MSM-IDUs is a third higher than among MSW-IDUs, suggesting elevated risk from injecting and possibly sexual transmission. These findings emphasise the need for public health interventions specifically targeted at MSM-IDUs.


Asunto(s)
Patógenos Transmitidos por la Sangre/aislamiento & purificación , Infecciones por VIH/epidemiología , Hepatitis C/epidemiología , Heterosexualidad , Homosexualidad Masculina , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adolescente , Adulto , Inglaterra/epidemiología , Femenino , Infecciones por VIH/diagnóstico , Hepatitis C/virología , Humanos , Masculino , Persona de Mediana Edad , Irlanda del Norte/epidemiología , Prevalencia , Medición de Riesgo , Gales/epidemiología , Adulto Joven
5.
Microbiol Spectr ; 10(1): e0078621, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-34985331

RESUMEN

Seroepidemiological studies to monitor antibody kinetics are important for assessing the extent and spread of SARS-CoV-2 in a population. Noninvasive sampling methods are advantageous for reducing the need for venipuncture, which may be a barrier to investigations, particularly in pediatric populations. Oral fluids are obtained by gingiva-crevicular sampling from children and adults and are very well accepted. Enzyme immunoassays (EIAs) based on these samples have acceptable sensitivity and specificity compared to conventional serum-based antibody EIAs and are suitable for population-based surveillance. We describe the development and evaluation of SARS-CoV-2 IgG EIAs using SARS-CoV-2 viral nucleoprotein (NP) and spike (S) proteins in IgG isotype capture format and an indirect receptor-binding-domain (RBD) IgG EIA, intended for use in children as a primary endpoint. All three assays were assessed using a panel of 1,999 paired serum and oral fluids from children and adults participating in school SARS-CoV-2 surveillance studies during and after the first and second pandemic wave in the United Kingdom. The anti-NP IgG capture assay was the best candidate, with an overall sensitivity of 75% (95% confidence interval [CI]: 71 to 79%) and specificity of 99% (95% CI: 78 to 99%) compared with paired serum antibodies. Sensitivity observed in children (80%, 95% CI: 71 to 88%) was higher than that in adults (67%, CI: 60% to 74%). Oral fluid assays (OF) using spike protein and RBD antigens were also 99% specific and achieved reasonable but lower sensitivity in the target population (78%, 95% CI [68% to 86%] and 53%, 95% CI [43% to 64%], respectively). IMPORTANCE We report on the first large-scale assessment of the suitability of oral fluids for detection of SARS-CoV-2 antibody obtained from healthy children attending school. The sample type (gingiva-crevicular fluid, which is a transudate of blood but is not saliva) can be self collected. Although detection of antibodies in oral fluids is less sensitive than that in blood, our study suggests an optimal format for operational use. The laboratory methods we have developed can reliably measure antibodies in children, who are able to take their own samples. Our findings are of immediate practical relevance for use in large-scale seroprevalence studies designed to measure exposure to infection, as they typically require venipuncture. Overall, our data indicate that OF assays based on the detection of SARS-CoV-2 antibodies are a tool suitable for population-based seroepidemiology studies in children and highly acceptable in children and adults, as venipuncture is no longer necessary.


Asunto(s)
Anticuerpos Antivirales/análisis , COVID-19/diagnóstico , Líquido del Surco Gingival/inmunología , Inmunoglobulina G/análisis , SARS-CoV-2/inmunología , Adolescente , Niño , Preescolar , Humanos , Técnicas para Inmunoenzimas , Lactante , Sensibilidad y Especificidad , Estudios Seroepidemiológicos
6.
J Med Virol ; 83(10): 1744-51, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21837790

RESUMEN

The ability to detect type-specific high risk HPV (HR-HPV) infections in samples from females and males is important for monitoring the epidemiology of HPV and the impact of vaccination. Type-specific detection concordance between paired urine and genital samples from females (n = 264) undergoing routine colposcopy and males (n = 88) attending a genito-urinary medicine clinic was evaluated using an in-house genotyping assay. The overall inter-rater agreement (κ) was 0.781 for female pairs and 0.346 for male pairs. Female urine had sensitivity for detection of HPV16/18 and HR-HPV of 75% and 84%, respectively, while male urine had sensitivities of 13% and 28%, respectively. Genital samples had a higher HPV DNA copy number than urine although a small proportion (10%) of urine samples had a higher copy number than the corresponding genital sample. The proportion of females with normal cytology positive for HPV16/18 was 19%, increasing to 57% in moderate or severely dyskaryotic samples. The same trend was seen in the corresponding urine (19-43%) compounded by the reduced sensitivity of this sample type. The HPV16 viral load in female genital samples, but not in urine, was weakly associated with cervical disease stage. Despite reduced sensitivity, urine appears to be an appropriate surrogate sample for type-specific HPV detection in females for epidemiological objectives. The lower sensitivity and lack of association between viral load and disease stage in urine suggest that urine may not be useful for clinical management of HPV infection. The utility of urine for type-specific detection in males is less certain.


Asunto(s)
Alphapapillomavirus/clasificación , Alphapapillomavirus/genética , Genitales Femeninos/virología , Genitales Masculinos/virología , Infecciones por Papillomavirus/diagnóstico , Orina/virología , ADN Viral/orina , Femenino , Genotipo , Humanos , Masculino , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Enfermedades del Cuello del Útero/diagnóstico , Enfermedades del Cuello del Útero/virología , Frotis Vaginal , Carga Viral
7.
Am J Epidemiol ; 170(3): 352-60, 2009 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19546152

RESUMEN

Changes in hepatitis C virus (HCV) prevalence from 1992 to 2006 were examined by using 24,311 records from unlinked anonymous surveillance of injecting drug users in England and Wales. Bayesian logistic regression was used to estimate annual prevalence, accounting for changing recruitment patterns (age, gender, injecting duration, geographic region, interactions) and the sensitivity and specificity of different oral fluid testing devices. After controlling for these differences, the authors found that the adjusted HCV prevalence decreased from 70% (95% credible interval: 62, 78) in 1992 to 47% (95% credible interval: 43, 51) in 1998 before rising again to 53% (95% credible interval: 48, 58) in 2006. Women injecting drug users had a higher HCV risk than did men (odds ratio = 1.50, 95% credible interval: 1.31, 1.73). Two regions (London and North West) had a markedly higher HCV prevalence than did the rest of England and Wales. Among individuals who had injected for less than 1 year, the adjusted HCV prevalence in 2006 was higher than that in 1992 (28% vs. 19%, respectively). HCV infection can be prevented. The public health challenge in England and Wales is to increase action in order to regain a downward trend in HCV risk and the benefit that has been lost since 1998.


Asunto(s)
Consumidores de Drogas/estadística & datos numéricos , Hepacivirus , Hepatitis C/epidemiología , Hepatitis C/etiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adolescente , Adulto , Teorema de Bayes , Inglaterra/epidemiología , Femenino , Encuestas Epidemiológicas , Hepacivirus/aislamiento & purificación , Humanos , Londres/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Gales/epidemiología
8.
BMC Infect Dis ; 9: 14, 2009 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-19203380

RESUMEN

BACKGROUND: Little is known about the prevalence of HIV or HCV in injecting drug users (IDUs) in Serbia and Montenegro. We measured prevalence of antibodies to HIV (anti-HIV) and hepatitis C virus (anti-HCV), and risk factors for anti-HCV, in community-recruited IDUs in Belgrade and Podgorica, and determined the performance of a parallel rapid HIV testing algorithm. METHODS: Respondent driven sampling and audio-computer assisted survey interviewing (ACASI) methods were employed. Dried blood spots were collected for unlinked anonymous antibody testing. Belgrade IDUs were offered voluntary confidential rapid HIV testing using a parallel testing algorithm, the performance of which was compared with standard laboratory tests. Predictors of anti-HCV positivity and the diagnostic accuracy of the rapid HIV test algorithm were calculated. RESULTS: Overall population prevalence of anti-HIV and anti-HCV in IDUs were 3% and 63% respectively in Belgrade (n = 433) and 0% and 22% in Podgorica (n = 328). Around a quarter of IDUs in each city had injected with used needles and syringes in the last four weeks. In both cities anti-HCV positivity was associated with increasing number of years injecting (eg Belgrade adjusted odds ratio (AOR) 5.6 (95% CI 3.2-9.7) and Podgorica AOR 2.5 (1.3-5.1) for >or= 10 years v 0-4 years), daily injecting (Belgrade AOR 1.6 (1.0-2.7), Podgorica AOR 2.1 (1.3-5.1)), and having ever shared used needles/syringes (Belgrade AOR 2.3 (1.0-5.4), Podgorica AOR 1.9 (1.4-2.6)). Half (47%) of Belgrade participants accepted rapid HIV testing, and there was complete concordance between rapid test results and subsequent confirmatory laboratory tests (sensitivity 100% (95%CI 59%-100%), specificity 100% (95%CI 98%-100%)). CONCLUSION: The combination of community recruitment, ACASI, rapid testing and a linked diagnostic accuracy study provide enhanced methods for conducting blood borne virus sero-prevalence studies in IDUs. The relatively high uptake of rapid testing suggests that introducing this method in community settings could increase the number of people tested in high risk populations. The high prevalence of HCV and relatively high prevalence of injecting risk behaviour indicate that further HIV transmission is likely in IDUs in both cities. Urgent scale up of HIV prevention interventions is needed.


Asunto(s)
Consumidores de Drogas , Seroprevalencia de VIH , Encuestas Epidemiológicas , Abuso de Sustancias por Vía Intravenosa/epidemiología , Serodiagnóstico del SIDA , Adulto , Pruebas Anónimas , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Hepatitis C/epidemiología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Montenegro/epidemiología , Prevalencia , Factores de Riesgo , Serbia/epidemiología
9.
AIDS ; 21(17): 2309-14, 2007 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-18090279

RESUMEN

OBJECTIVES: To investigate whether combining clinical data with the serological testing algorithm for recent HIV seroconversion (STARHS) reliably identifies otherwise unrecognized recent infections and observe their trends. DESIGN: Incorporation of STARHS into routine HIV diagnosis. METHODS: STARHS was applied to serum collected between 1996 and 2005 at HIV diagnosis and routine clinical/laboratory markers of recent infections were determined. The recent infections were identified by conventional means, by STARHS, and by both combined. RESULTS: Of 1526 infections diagnosed, 812 were new. Of these, 604 were in men who have sex with men (MSM); 208 in heterosexuals; 88% had serum available for STARHS, which identified 88 incident infections that would otherwise have been unrecognized (12% of all new infections, 34% of all recent infections). Of these, 88% reported recent high-risk sex; 47% reported seroconversion symptoms. STARHS confirmed recent infections in 71 of 74 (96%) known to be infected within 6 months by conventional methods. Combining both approaches, recent infections increased over time from 26% (1996) to 45% (2005) [P < 0.001]. STARHS results from 3% new diagnoses and 8% previous diagnoses were deemed false incident (associated with antiretroviral therapy, advanced disease or undetectable viral load). False incident results were only inexplicable in two individuals. CONCLUSION: Adjunctive use of STARHS with clinical data identified a high and increasing proportion of new HIV diagnoses as recent infections, confirming significant ongoing transmission. Since 2002, 50% of new diagnoses among MSM were recent infections. Identification of additional recent infections by STARHS enables effective intervention that may benefit the individual and reduce onward transmission.


Asunto(s)
Serodiagnóstico del SIDA/métodos , Algoritmos , Seropositividad para VIH/epidemiología , VIH , Homosexualidad Masculina , Enfermedad Aguda , Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Humanos , Incidencia , Masculino , Reino Unido/epidemiología , Sexo Inseguro
10.
Trop Med Int Health ; 12(11): 1323-6, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17949396

RESUMEN

OBJECTIVE: To determine the specificity of the Abbott Murex HIV antigen/antibody combination enzyme immunoassay (EIA) for the diagnosis of HIV infection in Tanzania. METHODS: A cross-sectional survey of 7333 Tanzanian adolescents and young adults was carried out. Sera testing positive by the Murex assay were further evaluated using a battery of other EIA which detect either antibody to HIV-1 or p24 antigen, and by PCR using pol primers. RESULTS: Of the 674 sera testing positive by the Murex assay, only 53 (7.9%) were confirmed. The specificity of the Murex assay was 91.5%. CONCLUSIONS: Serological tests for HIV may perform differently in different populations. New diagnostic tests should not be introduced into populations in which they have not been evaluated.


Asunto(s)
Serodiagnóstico del SIDA/métodos , Infecciones por VIH/diagnóstico , Técnicas para Inmunoenzimas/normas , Juego de Reactivos para Diagnóstico , Adolescente , Adulto , Reacciones Antígeno-Anticuerpo , Estudios Transversales , Anticuerpos Anti-VIH/inmunología , Humanos , Sensibilidad y Especificidad , Tanzanía
11.
Am J Public Health ; 97(3): 478-85, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17018827

RESUMEN

OBJECTIVES: We examined risk factors for syphilis infection among injection drug users in 3 Russian Federation cities, focusing particular attention on the potential roles of gender and sex work. METHODS: We conducted a cross-sectional survey of injection drug users in Moscow, Volgograd, and Barnaul, collecting behavioral data and testing for antibodies to Treponema pallidum. Associations between presence of antibodies to T pallidum and covariates were explored. RESULTS: Overall, the prevalence of antibodies to T pallidum was 11% (95% confidence interval=9.7%, 13.1%). Syphilis was associated with involvement in sex work and with gender in Moscow and Barnaul but not in Volgograd. Female injection drug users not involved in sex work were more likely than men to be younger and to have recently begun to inject; female injection drug users involved in sex work were more likely than those not involved in sex work to inject daily. CONCLUSIONS: Syphilis transmission dynamics varied by region. Sex work can increase syphilis risk among injection drug users, potentially feeding the momentum of sexually transmitted HIV and syphilis among noninjectors. Targeted interventions are needed to reduce both sexual and injection risk behaviors among injection drug users.


Asunto(s)
Anticuerpos Antibacterianos/análisis , Trabajo Sexual/estadística & datos numéricos , Abuso de Sustancias por Vía Intravenosa/epidemiología , Sífilis/epidemiología , Treponema pallidum/inmunología , Salud Urbana/estadística & datos numéricos , Adulto , Condones/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Masculino , Moscú/epidemiología , Mucosa Bucal/microbiología , Análisis Multivariante , Prevalencia , Medición de Riesgo , Factores de Riesgo , Asunción de Riesgos , Federación de Rusia/epidemiología , Distribución por Sexo , Parejas Sexuales , Abuso de Sustancias por Vía Intravenosa/microbiología , Sífilis/microbiología , Sífilis/transmisión , Sexo Inseguro/estadística & datos numéricos
12.
Int J Drug Policy ; 46: 28-33, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28586700

RESUMEN

BACKGROUND: While people who inject drugs (PWID) typically use peripheral veins, some inject into their central veins, including the femoral and jugular veins. Injection into the jugular vein can have serious adverse health consequences, including jugular vein thrombosis, deep neck infections, pneumothorax, endocarditis and sepsis. This study examined the prevalence of, and factors associated with, jugular vein injection among a large sample of PWID in the United Kingdom. METHOD: Unlinked anonymous surveys (2011-14) recruited PWID from agencies providing services to this population. Self-reported demographic and injection-related data were collected from consenting respondents using a brief questionnaire and dried blood spot samples were tested for exposure to HIV, hepatitis C virus (HCV) and hepatitis B virus (HBV). Univariate and multivariable logistic regression were used to examine factors associated with jugular vein injection. RESULTS: Among 5261 PWID, one third had injected into a central vein in the previous 28 days, including 6% (n=339) who had injected into their jugular vein and 1% (n=52) who had used this site exclusively for recent injections. Factors independently associated with recent jugular vein injection in multivariable analysis included female gender, a lifetime history of imprisonment, sharing needles and syringes, poly-drug injection and injection into multiple body sites. Jugular vein injection was also associated with experiencing injection-related injuries, although no associations were identified with respect to exposure to blood borne viral infections. CONCLUSION: A significant minority of PWID inject into the jugular vein in the United Kingdom. Public health responses should investigate ways to support and promote good injection site management in order to minimise vascular damage and reduce problems with peripheral venous access. Women who inject drugs, PWID with a history of imprisonment and those people who are experiencing early signs of injection-related skin and soft tissue injuries are priority sub-populations for interventions.


Asunto(s)
Venas Yugulares , Compartición de Agujas/estadística & datos numéricos , Traumatismos de los Tejidos Blandos/etiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto , Femenino , Humanos , Modelos Logísticos , Masculino , Prevalencia , Prisioneros/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales , Abuso de Sustancias por Vía Intravenosa/complicaciones , Encuestas y Cuestionarios , Reino Unido/epidemiología
13.
AIDS ; 20(16): 2120-3, 2006 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-17053361

RESUMEN

We found a high prevalence of HIV among injecting drug users (IDU) 54% in Tallinn and 90% in Kohtla Jarve, Estonia. Risk factors for HIV in Tallinn included use of the drug 'china white', being registered as an IDU at a drug treatment clinic, and sharing injecting equipment with sex partners. Differences existed in risk behaviour between the cities. An urgent scale-up of HIV prevention is needed. It is also important to explore how local 'risk environments' mediate the risk of HIV transmission.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Estudios Transversales , Estonia/epidemiología , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo , Asunción de Riesgos , Abuso de Sustancias por Vía Intravenosa/epidemiología
14.
Addiction ; 101(2): 252-66, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16445554

RESUMEN

OBJECTIVES: To estimate the prevalence of HIV, hepatitis C virus (HCV) and syphilis in injecting drug users (IDUs) in Russia. METHODS: Unlinked anonymous cross-sectional survey of 1473 IDUs recruited from non-treatment settings in Moscow, Volgograd and Barnaul (Siberia), with oral fluid sample collection for HIV, HCV antibody (anti-HIV, anti-HCV) and syphilis testing. RESULTS: Prevalence of antibody to HIV was 14% in Moscow, 3% in Volgograd and 9% in Barnaul. HCV prevalence was 67% in Moscow, 70% in Volgograd and 54% in Barnaul. Prevalence of positive syphilis serology was 8% in Moscow, 20% in Volgograd and 6% in Barnaul. Half of those HIV positive and a third of those HCV positive were unaware of their positive status. Common risk factors associated with HIV and HCV infection across the cities included both direct and indirect sharing of injecting equipment and injection of home-produced drugs. Among environmental risk factors, we found increased odds of anti-HIV associated with being in prison in Moscow, and some association between official registration as a drug user and anti-HIV and anti-HCV. No associations were found between sexual risk behaviours and anti-HIV in any city. CONCLUSIONS: HIV prevalence among IDUs was markedly higher than city routine surveillance data suggests and at potentially critical levels in terms of HIV prevention in two cities. HCV prevalence was high in all cities. Syphilis prevalence highlights the potential for sexual risk and sexual HIV transmission. Despite large-scale testing programmes, knowledge of positive status was poor. The scaling-up of harm reduction for IDUs in Russia, including sexual risk reduction, is an urgent priority.


Asunto(s)
Infecciones por VIH/epidemiología , Hepatitis C/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Sífilis/epidemiología , Adolescente , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/transmisión , Hepatitis C/transmisión , Humanos , Masculino , Prevalencia , Federación de Rusia/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología
15.
J Acquir Immune Defic Syndr ; 71(3): 331-7, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26361173

RESUMEN

BACKGROUND: Infection risks among people who inject drugs (PWID) are widely recognized, but few studies have focused on image and performance enhancing drugs (IPEDs). Globally, concern about IPED injection has increased and, in the United Kingdom, IPED injectors have become the largest group using Needle and Syringe Programmes. Blood-borne virus prevalence trends among IPED injectors are explored. METHOD: Data from 2 surveys of IPED injectors (2010-2011; 2012-2013) and the national bio-behavioral surveillance system for PWID (1992-1997; 1998-2003; 2004-2009) were merged. Psychoactive drug injectors and women were excluded. Logistic regression analyses explored temporal changes. RESULTS: Between 1992 and 2009, median age increased from 25 to 29 years (N = 1296), years injecting from 2 to 4. There were 53 men who had sex with men (MSM). Overall, 0.93% had HIV, 4.4% ever had hepatitis B (HBV), and 3.9% hepatitis C (HCV, from 1998, N = 1083). In multivariable analyses, HIV increased in 2004-2009 [adjusted odds ratio (AOR) = 10 (95% confidence interval (CI): 0.94 to 106) vs. 1992-2003], and remained elevated (AOR = 4.12, 95% CI: 0.31 to 54, 2012-2013); HBV also increased in 2004-2009 (AOR = 3.98, 95% CI: 1.59 to 9.97). HCV prevalence increase was only borderline significant (AOR = 2.47, 95% CI: 0.90 to 6.77, 2010-2011). HIV and HBV were associated with MSM and HCV with sharing needles/syringes. Uptake of diagnostic testing for HIV and HCV, and HBV vaccination increased (to 43%, 32% and 44% respectively). Condom use was consistently poor; needle/syringe sharing occurred. CONCLUSION: Blood-borne virus prevalences among IPED injectors have increased and for HIV, is now similar to that among psychoactive drug injectors. Targeted interventions to reduce risks are indicated.


Asunto(s)
Infecciones por VIH/complicaciones , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Sustancias para Mejorar el Rendimiento/administración & dosificación , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Estudios Transversales , Recolección de Datos , Inglaterra/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/etiología , Hepatitis B/epidemiología , Hepatitis B/etiología , Hepatitis C/epidemiología , Hepatitis C/etiología , Homosexualidad Masculina , Humanos , Modelos Logísticos , Masculino , Prevalencia , Factores de Riesgo , Abuso de Sustancias por Vía Intravenosa/epidemiología , Encuestas y Cuestionarios , Factores de Tiempo , Gales/epidemiología , Adulto Joven
16.
AIDS ; 19(11): 1207-14, 2005 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-15990575

RESUMEN

OBJECTIVE: To describe trends in HIV prevalence among injecting drug users in England and Wales between 1990 and 2003. METHODS: Analysis of surveillance data from voluntary unlinked anonymous cross-sectional surveys collecting oral fluid samples and behavioural information from injecting drug users recruited from both drug agency (n = 24,304) and community settings (n = 3628). RESULTS: HIV prevalence in England and Wales declined from 5.9% in 1990 to 0.6% in 1996 and then remained stable until 1999, after which it increased to 1.4% in 2003. Few HIV infections were detected among short-term injectors between 1994 and 1999, but in recent years prevalence among this group has increased. Other factors associated with higher odds of HIV infection were being recruited in London and from community settings, and ever having had a voluntary confidential HIV test. Incidence estimated through a force of infection model was 2.8% per annum among those injecting for less than a year in London between 1998 and 2003. CONCLUSIONS: These data suggest that incidence and prevalence of HIV may have increased, whereas other indicators suggest an increase in risk behaviour. It is critical that harm reduction measures are reinvigorated, and evolve in response to changes in drug use risk behaviours and policy.


Asunto(s)
Infecciones por VIH/epidemiología , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adolescente , Adulto , Inglaterra/epidemiología , Infecciones por VIH/transmisión , Humanos , Persona de Mediana Edad , Prevalencia , Asunción de Riesgos , Gales/epidemiología
17.
Int J STD AIDS ; 16(11): 749-54, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16303071

RESUMEN

The objective of this study was to estimate the prevalence of hepatitis C virus (HCV) infection and co-infection with HIV among injecting drug users (IDUs) in Togliatti City, Russia. Unlinked anonymous cross-sectional survey of IDUs recruited from community settings, with oral fluid sample collection for HCV and HIV antibody (anti-HCV, anti-HIV) testing, was carried out. The anti-HCV prevalence was 87% (357/411), anti-HIV prevalence 56% (234/418), and 93% (214/230) of HIV-positive IDUs were co-infected with HCV. Only 23% (94/411) of those HCV positive self-reported as such. In an adjusted model, increased odds of HCV positivity were associated with needle and syringe, as well as injecting paraphernalia sharing in the last four weeks. IDUs injecting more than once with the same needle also had raised odds. There were no marked associations between HCV positivity and the duration of injecting or age group. Almost all IDUs were HCV positive, and almost all HIV-positive IDUs were HCV co-infected. There is an urgent need to maximize syringe distribution coverage, develop health promotion targeting HCV prevention for IDUs, and improve access among IDUs to treatments for HIV and HCV infection.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Hepatitis C/complicaciones , Hepatitis C/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Femenino , Anticuerpos Anti-VIH/sangre , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Prevalencia , Factores de Riesgo , Federación de Rusia/epidemiología
18.
PLoS One ; 10(4): e0120810, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25848769

RESUMEN

To determine uptake of home sampling kit (HSK) for STI/HIV compared to clinic-based testing, whether the availability of HSK would increase STI testing rates amongst HIV infected MSM, and those attending a community-based HIV testing clinic compared to historical control. Prospective observational study in three facilities providing STI/HIV testing services in Brighton, UK was conducted. Adult MSM attending/contacting a GUM clinic requesting an STI screen (group 1), HIV infected MSM attending routine outpatient clinic (group 2), and MSM attending a community-based rapid HIV testing service (group 3) were eligible. Participants were required to have no symptomatology consistent with STI and known to be immune to hepatitis A and B (group 1). Eligible men were offered a HSK to obtain self-collected specimens as an alternative to routine testing. HSK uptake compared to conventional clinic-based STI/HIV testing in group 1, increase in STI testing rates due to availability of HSK compared to historical controls in group 2 and 3, and HSK return rates in all settings were calculated. Among the 128 eligible men in group 1, HSK acceptance was higher (62.5% (95% CI: 53.5-70.9)) compared to GUM clinic-based testing (37.5% (95% CI: 29.1-46.5)), (p = 0.0004). Two thirds of eligible MSM offered an HSK in all three groups accepted it, but HSK return rates varied (highest in group 1, 77.5%, lowest in group 3, 16%). HSK for HIV testing was acceptable to 81% of men in group 1. Compared to historical controls, availability of HSK increased the proportion of MSM testing for STIs in group 2 but not in group 3. HSK for STI/HIV offers an alternative to conventional clinic-based testing for MSM seeking STI screening. It significantly increases STI testing uptake in HIV infected MSM. HSK could be considered as an adjunct to clinic-based services to further improve STI/HIV testing in MSM.


Asunto(s)
Atención a la Salud/estadística & datos numéricos , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/prevención & control , Manejo de Especímenes/métodos , Adolescente , Adulto , Instituciones de Atención Ambulatoria , Autoevaluación Diagnóstica , Infecciones por VIH/psicología , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Estudios Prospectivos , Enfermedades de Transmisión Sexual/psicología , Adulto Joven
19.
AIDS ; 18(2): 265-72, 2004 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-15075544

RESUMEN

OBJECTIVE: To estimate the trend in HIV incidence between 1995 and 2001 in men who have sex with men (MSM) attending sexually transmitted infection (STI) clinics in the UK. DESIGN: The Serological Testing Algorithm for Recent HIV Seroconversion (STARHS) was applied to serum specimens from MSM attending 15 STI clinics collaborating in an HIV unlinked anonymous prevalence serosurvey. METHODS: STARHS was performed on anti-HIV-1 positive specimens and HIV incidence rates determined. Specimens from MSM with previously diagnosed HIV or an AIDS defining condition were excluded. National data on uptake of antiretroviral therapy (ART), AIDS mortality and diagnoses of gonorrhoea in MSM were used to aid interpretation of the HIV incidence findings. RESULTS: Of 43,100 specimens collected from MSM 3565 were anti-HIV-1 positive. Of these, 1645 were eligible and available for STARHS testing, of which 317 were deemed to come from recently acquired infections. The overall estimated annual incidence ranged from 1.5% (1999) to 3.3% (1996). In 2001 it was 2.45%, with a 3.1% incidence in London and 1.0% elsewhere. No significant trends in HIV incidence were found. CONCLUSIONS: Despite the widespread use of ART there was no significant decline in HIV incidence. Individuals whose HIV infection has been diagnosed should be less infectious. However, over 20% of infections in MSM remain undiagnosed, many with acute STI, and this pool of unmanaged HIV infection may be an important driver of the ongoing epidemic. Initiatives to diagnose and treat a greater proportion of HIV infections may be the key to reducing HIV incidence in MSM.


Asunto(s)
Infecciones por VIH/epidemiología , VIH-1 , Homosexualidad Masculina , Adulto , Anciano , Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Humanos , Incidencia , Masculino , Reino Unido/epidemiología
20.
AIDS ; 16(13): F25-31, 2002 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-12218407

RESUMEN

OBJECTIVE: To establish the prevalence of antibodies to HIV (anti-HIV) and associated risk factors among injecting drug users (IDU) in Togliatti City, Samara Oblast, Russian Federation. DESIGN: An unlinked anonymous cross-sectional community recruited survey with oral fluid sample collection. METHODS: Between September and October 2001, 426 IDU were recruited by trained fieldworkers. Participants completed an interviewer administered questionnaire, and oral fluid samples were tested for anti-HIV. Univariate and multivariate analyses compared potential risk factors for anti-HIV. RESULTS: Anti-HIV prevalence was 56% (234/418). Three-quarters of anti-HIV-positive IDU (74%) were unaware of their positive status. In an adjusted model, the odds of HIV infection were higher among IDU who had ever injected home-produced drugs, who reported injecting with used needles and syringes in the past 4 weeks, and who were living in one particular district of the city (Komsomolksii). CONCLUSION: The high prevalence of HIV, and a recent increase in HIV detected through routine screening tests since 2000, suggests that an explosive epidemic has occurred among IDU in Togliatti City. In the face of currently inadequate HIV prevention coverage among IDU, this has urgent implications for maximizing the distribution of sterile injecting equipment as well as for enhancing sexual risk reduction. Recognizing that it is likely that similar explosive epidemics are taking place in other Russian cities, we recommend community-wide HIV prevention coverage supported by city and state policies oriented to harm reduction.


Asunto(s)
Anticuerpos Anti-VIH/análisis , Infecciones por VIH/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Serodiagnóstico del SIDA , Adulto , Estudios Transversales , Brotes de Enfermedades , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Humanos , Masculino , Boca/inmunología , Prevalencia , Asunción de Riesgos , Federación de Rusia/epidemiología , Encuestas y Cuestionarios
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