Uso de heroína inyectada y el riesgo de hepatitis C en tres ciudades de Colombia / Use of injected heroin and risk of hepatitis C in three cities in Colombia

RESUMEN: Introducción: La hepatitis C es uno de los grandes problemas de salud pública en el mundo, especialmente por su alta transmisibilidad por vía inyectada. Objetivo: Identificar la prevalencia de la infección por VHC, y factores asociados en usuarios de drogas psicoactivas inyectables en tres ciudades (Armenia, Bogotá y Cúcuta) de Colombia. Métodos: Estudio descriptivo transversal en 668 usuarios de drogas inyectables captados a través de muestreo guiado por el respondiente, a quienes se indagó sobre características demográficas y comportamientos de riesgo. Se utilizó la prueba de Anticuerpos, tomado en papel de filtro y se confirmaron los casos de VHC, con pruebas de carga viral de RNA. Se estimó la prevalencia de VHC y los factores asociados con pruebas estadísticas Chi-cuadrado y se calcularon razones de prevalencia crudas y ajustadas con regresión logística usando RDSAT y SPSS. Resultados: La prevalencia de infección por VHC fue del 17,5% y se encontraron como factores que aumentan la prevalencia de hepatitis: tener VIH, inyectarse con otra persona portadora del virus, utilizar dosis de una jeringa que estaba compartiendo, inyectarse con una jeringa casera y consumir marihuana. Como factor que reduce la prevalencia, el adquirir jeringas en droguerías u otras tiendas. Conclusión: Se evidencia un consumo establecido de drogas por vía inyectada, poniendo de relieve la importancia de generar intervenciones para la reducción de daños y la prevención de hepatitis C en estas tres ciudades del país.

ABSTRACT: Introduction: Hepatitis C is one of the most neglected diseases by governments internationally. Objective: Identify the prevalence of hepatitis C and associated injection drug users in three cities of factors Colombia. Methods: Cross-sectional study of 668 injecting drug users recruited through respondent-driven sampling, inquired about demographic characteristics and risk behaviors. Laboratory testing was used on filter paper and cases of hepatitis C viral load tests with RNA were confirmed. Hepatitis C prevalence and associated factors was estimated with Chi-square test statistics and reasons for crude and adjusted prevalence were calculated using logistic regression. Results: The prevalence of hepatitis C was 17.5% and were found as factors that increase the prevalence of hepatitis: having HIV, injecting another person carrying the virus dose used was sharing a syringe, injected with a syringe and consume marijuana. As a factor that reduces the prevalence, purchase syringes in drug stores or other stores. Conclusion: This research evidence established consumption of drugs by injection , and the presence of hepatitis C in social networks of IDUs and highlights the importance of developing interventions for harm reduction and prevention of hepatitis C in this population these three cities.

Hematological particularities and co-infections in injected drug users with AIDS

HIV patients infected through injected drug use have poorer prognosis than other groups. We evaluated the hematological alterations and rates of co-infections in injected drug use patients with AIDS. Injected drug use patients were younger, predominantly of male gender, and presented lower CD4, total lymphocyte, and platelet counts, but not neutrophil count, than control group. Injected drug use patients had a higher rate of hepatitis C and mycobacteria infection. Furthermore, all injected drug use patients with hemoglobin <10.0 g dL-1 and lymphocyte <1000 µL-1 had CD4 count lower than 100 µL-1. In conclusion, HIV-infected injected drug use patients constitute a special group of patients, and hemoglobin concentration and lymphocyte count can be used as surrogate markers for disease severity.

Clinical characteristics, spontaneous clearance and treatment outcome of acute hepatitis C: a single tertiary center experience

Acute hepatitis C is rarely diagnosed due to its predominantly asymptomatic course. However, early treatment results in viral eradication in a high number of patients thus, preventing chronicity. The aim of our study was to describe our experience with patients with acute hepatitis C virus [HCV] infection who presented and followed-up in our liver unit, pointing on treatment strategy, and outcome. Retrospective, descriptive study of 30 patients with acute HCV infection [26 males and 4 females] with a mean age of 32 years. The source of infection was mainly injection drug use in 17/30 [56.7] and medical procedures 6/30 [20%]. Twenty patients [66.6%] were symptomatic. HCV-ribonucleic acid [RNA] was detectable at presentation in 26 [86.7%] patients. The genotype distribution was: 13/26 [50%] genotype 1, 3/26 [11.5%] genotype 2, 8/26 [30.8%] genotype 3 and 2/26 [7.7%] genotype 4. Totally, 9 patients [30%] experienced spontaneous viral eradication. No significant differences could be documented between patients who spontaneously cleared the virus and those who had viral persistence. Thirteen patients [44%] were treated with peginterferon-based regimen. All patients [100%] achieved non-detectable HCV-RNA and had normal serum alanine aminotransferase levels at the end of the treatment. Eleven patients achieved sustained virologic response [SVR], one relapsed and one was lost to follow-up. The overall SVR rate was 84.6%. None of the patients required dose reduction or stopped the treatment due to side effects. In conclusion, early initiation of anti-viral treatment in patients with acute hepatitis C results in high-SVR rates [independently of genotype] and is well-tolerated

Difficulties with interferon treatment in former intravenous drug users

OBJECTIVES: Intravenous drug use accounts for most of the new hepatitis C infections worldwide. Although there is an urgent need for antiviral treatment of infected intravenous drug users (IDUs), several factors compromise their treatment including lack of treatment adherence and high dropout rate. The aim of this study was to compare antiviral treatment-related problems among former IDUs to HCV-infected patients without a history of IDU. METHODS: This was a retrospective chart review of HCV-infected IDUs who received combined antiviral therapy at the Hepatology Outpatient Clinic of Szent László Hospital between 1 January 2006 and 31 December 2008. A control group of interferon treated patients with no history of IDU matched for age and sex was selected. RESULTS: Dropout rate was significantly higher in the IDU group (p = 0.016). Treatment response at the 12th week of treatment was significantly better in the IDU group (p = 0.004). Significantly more IDUs underwent antiviral treatment while in prison (p = 0.008). CONCLUSIONS: In this study higher dropout rate was found among IDUs. IDUs had a better response rate to antiviral therapy compared to controls. More attention should be paid to factors that worsen treatment adherence of IDUs - particularly lack of abstinence - in order to increase the effectiveness of antiviral therapy.

[Compression of depression frequency in HIV positive and HIV negative among IV drug abusers]

Today, HIV infectious and IV drug abusers have a near relationship; especially IV is an important matter in IRAN. A big number of abusers suffered from HIV and capable to psychiatric disorder. Evaluation of Depression Frequency in HIV Positive and HIV Negative among IV Drug Abusers. In a cross sectional, descriptive study, frequency of depression was evaluated between HIV positive and HIV negative among IV drug abusers. Twenty hundred seventy drug abusers [90 HIV+, 180 HIV-] were enrolled in the study. Data was collected by Beck Depression Inventory [BDI] questionnaire for depression and checklist for demographic features. Mean average age of starting injection was 38.25 +/- 7.1 years old. Frequency of depression in HIV positive individuals was 79% and 7.8% of them had major depression but in HIV negative individuals, 60% suffering from depression and 7.1% of them had major depression. Frequency of depression among HIV positive individuals is more than HIV negative individuals. So is suggested to pay more attention and better evaluation on psychiatric disorder of IV drug abusers with HIV

Pacemaker lead thrombo-endocarditis in an intravenous drug abuser

We report a 30-year-old male intravenous drug abuser presenting with persistent pacemaker lead thrombosis with superimposed pacemaker lead endocarditis. He underwent urgent surgery, but expired due to refractory sepsis. This case confirms that patients with pacemakers are at risk of developing pacemaker lead thrombosis. In addition, they are at high risk of developing pacemaker lead endocarditis if additional risk factors for endocarditis are present. We believe this case report is unusual on account of pacemaker lead thrombosis as well as endocarditis occurring in a patient with history of intravenous drug abuse. Whether pacemaker patients with multiple leads need to be on long-term antiplatelet or anticoagulation therapy necessitates further studies

Prevalence and genotypes of hepatitis C virus among injecting drug users from Salvador-BA, Brazil

Hepatitis C virus (HCV) is the major infectious disease agent among injecting drug users (IDUs), with seroprevalence ranging from 50-90 percent. In this paper, serological and virological parameters were investigated among 194 IDUs, 94 ex-IDUs and 95 non-IDUs that were sampled by the "snowball" technique in three localities renowned for both intense drug use and trafficking activities in Salvador, Brazil. The majority of the participants were male, but sex and mean age differed significantly between IDUs/ex-IDUs and non-IDUs (p < 0.05). Anti-HCV screening revealed that 35.6 percent, 29.8 percent and 5.3 percent of samples from IDUs, ex-IDUs and non-IDUs, respectively, were seropositive. HCV-RNA detection confirmed that the prevalence of infection was 29.4 percent, 21.3 percent and 5.3 percent for IDUs, ex-IDUs and non-IDUs, respectively. Genotyping analysis among IDUs/ex-IDUs determined that 76.9 percent were infected with genotype 1, 18.5 percent with genotype 3 and 4.6 percent with a mixed genotype; this result differed significantly from non-IDUs, where genotype 3 was the most frequent (60 percent), followed by genotype 1 (20 percent) and a mixed genotype (20 percent). We report a significantly higher prevalence of HCV infection in IDUs/ex-IDUs compared to the control group (p < 0.001). Although the sample size of our study was small, the differences in HCV genotype distribution reported herein for IDUs/ex-IDUs and non-IDUs warrant further investigation.

Infective endocarditis among hospitalized intravenous drug user patients in the south west of Iran

To determine the frequency of Infective Endocarditis [IE], clinical, echocardiographic and microbiological status at a teaching hospital in Ahvaz, South West Iran. Medical records of 323 Intravenous Drug User [IDU] inpatients from 2001 to 2006 were reviewed, out of which 33 cases that fulfilled the Duke criteria for diagnosis were included in the present study. The patients' characteristics, clinical findings, microbiological findings, echocardigraphic and comorbidities data were extracted. Data of patients with IE and without IE were compared in SPSS using t-test and chi square test. Patients with IE were 32 male and one female cases with a mean age of 26.2 years. Non IE patients were 288 male and two female cases with mean age of 37.8 years. Nineteen of our patients were HIV positive. There was statistically significant difference between HIV-positive and HIV-negative patients. Weight loss and fever were the commonest clinical findings. Staphylococcus aureus was the most common organism [24.2%] followed by coagolase negative staphylococcus [15.1%], most of them were methiciline resistant. Tricuspid valve was involved in 33.3% of cases. Frequency of Infective Endocarditis [IE] among Intravenous Drug User [IDU] is higher than reported in earlier studies. HIV infection increases the risk of IE. Methicilin resistant Staphylococcus aureus is the commonest organism. Tricuspid is the commonest involved cardiac valve

Septic arthritis of sternoclavicular joint: a case report of a rare finding in injecting drug users

The sternoclavicular joint is an unusual site for bacterial infection. In this case, we describe a 25-year-old man who presented to the emergency department with fever, chills, limited range of motion in the right upper limb along with complaints of severe pain and tenderness in the right upper chest wall and shoulder. He was admitted to the hospital for further evaluation. This patient admitted to a history of injecting heroin use during the previous three months. The diagnosis of septic arthritis of the right sternoclavicular joint was confirmed by blood culture and MRI of the sternoclavicular joint. This case is, to the best of our knowledge, the 25th recorded staphylococcal septic sternoclavicular arthritis. He received appropriate intravenous antibiotic therapy and subsequently was discharged two weeks later with complete clinical and laboratory recovery

Prevalence of selected sexually and blood-borne infections in Injecting drug abuser inmates of bandar abbas and roodan correction facilities, Iran, 2002

Human Immunodeficiency Virus (HIV) and other blood borne viral infections like hepatitis B virus (HBV) and hepatitis C virus (HCV) are major health issues especially in young and growing population of developing countries. All around the globe correctional facilities are known as potential source of spreading such disease. During summer 2002, HIV, HCV antibodies, hepatitis B surface (HBs) antigen and rapid plasma reagin (RPR) test were checked in venous blood samples of 252 injecting drug abuser prisoners from correctional facilities in southern Iran. Overall HIV, HCV and HBV infection rate was 15.1 percent (38/249), 64.8 percent (163/249), and 4.7 percent (12/249), respectively. HCV infection rate of HIV positive cases was 94 percent (35/38). All RPR results were negative. Duration of previous drug abuse and imprisonment were correlated with HIV and HCV infection (p value = 0.0003 and 0.015 & p value =0.02 and 0.02). Considering the higher prevalence of HIV and HCV infection in correctional facilities compared to general population of Iran, warrants immediate multidisciplinary approaches targeted at controlling further spread of these infections primarily among prisoners and secondarily preventing them to act as carrier to general population.

Prevalence of hepatitis C virus infection and associated factors among male illicit drug users in Cuiabá, Mato Grosso, Brazil

Intravenous drug injection has been reported as the main risk factor for hepatitis C virus (HCV) infection. The aim of the present study was to describe the prevalence and the epidemiological profile of HCV infection among abusers of illegal injected and non-injected drugs in Cuiabá, state of Mato Grosso, Central Brazil. A cross-sectional study including 314 male drug users from eight detoxification centres was performed. Out of 314 subjects studied, 48 (15.2 percent) were intravenous drug users. Participants were interviewed and had blood samples taken and tested for the presence of anti-HCV antibodies. Positive samples were tested for the presence of HCV RNA. Genotyping was performed on HCV RNA-positive samples. The overall prevalence of anti-HCV antibodies was 6.4 percent (n = 20). Out of 20 anti-HCV antibody-positive subjects, 16 (80 percent) were also HCV RNA-positive. Genotype 1 predominated (75 percent), followed by 3a (25 percent). Subtype 1a was more common than 1b. HCV infection was more prevalent among intravenous drug users (33 percent) than non-injecting users (1.5 percent). Logistic regression analyses showed independent associations between HCV infection and intravenous drug use, imprisonment and increasing age. In the present study, injecting drug use was the factor most strongly associated to HCV infection and inhaling or sniffing did not represent an increased susceptibility to infection.

Tendências da epidemia de AIDS entre subgrupos sob maior risco no Brasil, 1980-2004 / Trends in the AIDS epidemic in groups at highest risk in Brazil, 1980-2004

O presente trabalho tem por objetivo apresentar as tendências da epidemia de AIDS em grupos populacionais sob maior risco no Brasil. A técnica de análise discriminante foi utilizada para reclassificação dos casos masculinos com categoria de exposição ignorada em um dos três grupos homens que fazem sexo com homens (HSH), usuários de drogas injetáveis (UDI) ou heterossexuais. Foram estimadas as taxas de incidência de AIDS por sexo e categoria de exposição no período 1980-2004. No período 1980-1988, os casos homossexuais ou bissexuais masculinos correspondiam a 63,6 por cento dos casos, e a proporção de mulheres era de 10 por cento. Posteriormente, há um decréscimo importante no papel desempenhado pelos HSH e ocorre um acréscimo nas outras categorias de exposição. Apesar das tendências de decréscimo para as incidências de casos HSH e UDI e acréscimo entre os heterossexuais masculinos e as mulheres, quando as taxas de incidência são comparadas o risco é maior entre os HSH e UDI. A análise da dinâmica da epidemia de AIDS no Brasil mostra a importância dos grupos HSH e UDI masculinos enquanto grupos de risco diferenciado.

The objective of this paper was to present the trends in the AIDS epidemic in the population groups at highest risk in Brazil. Discriminant analysis was used to reclassify cases with unknown risk into one of the three groups: IDU (injecting drug users), MSM (men who have sex with men), and heterosexuals. AIDS incidence rates by gender and exposure category were estimated for the period 1980-2004. In 1980-1988, 63.6 percent of AIDS cases were homosexual or bisexual males and 10 percent were females. Since 1988, there has been a decrease in the proportion of MSM and an increase in the other categories. Despite the incidence trends observed by exposure category, when the incidence rates were compared, the risk was much higher among MSM as compared to heterosexuals. Analysis of the AIDS epidemic dynamics in Brazil emphasizes the importance of MSM and male IDU as higher-risk groups.

Isolated pulmonary valve endocarditis

Infective endocarditis is one of the most severe complications of parenteral drug abuse. The outstanding clinical feature of infective endocarditis in intravenous drug abusers is the high incidence of right-sided valve infection, and the tricuspid valve is involved in 60% to 70% of the cases. We herein report a case of isolated pulmonic valve infective endocarditis with a native pulmonary valve

Risk of hepatitis C infection among injection drug users in Mizoram, India.

BACKGROUND & OBJECTIVE: Prevalence of injection drug users (IDUs) is high in the northeastern region of India. This coupled with unsafe injecting practices as well as practice of tattooing in remote tribal areas call for baseline data on the prevalence of parentally transmitted viral diseases. In the present study we aimed to measure the risk behaviours and seroprevalence of hepatitis C virus (HCV) antibodies amongst IDUs of Mizoram, a State of the northeast India. METHODS: A cross-sectional study was conducted in 2004-2005 amongst IDUs (including female sex workers) who had injected in the past six months and were unaware of their HCV/HIV status. They were recruited from various drop-in centers from Aizawl, Mizoram, and screened for anti-HCV antibodies using 3(rd) generation HCV EIA and recombinant immunoblot assay (RIBA). RESULTS: The prevalence of HCV antibodies was 71.2 per cent among the active IDUs. On univariate analysis increasing duration of injection, syringe sharing and heroin (diacetylmorphine) injectors were at a significantly higher risk of acquiring HCV antibodies (P<0.001). On multivariate analysis, HCV antibody prevalence showed a strong association with the type of drugs injected (P=0.001), frequency of injecting (P=0.013), multiplicity of drugs abused (P=0.004), and needle syringe sharing (P=0.003). INTERPRETATION & CONCLUSION: Unsafe injecting practices were found to be associated with a higher risk of acquiring hepatitis C infection. Our findings showed that syringe and needle exchange programme alone was not sufficient as a preventive strategy for control of hepatitis C infection among IDUs of Aizawl.

HIV and AIDS in Bangladesh.

Bangladesh initiated an early response to the HIV epidemic starting in the mid-1980s. Since then, the response has been enhanced considerably, and many HIV-prevention interventions among the most at-risk populations and the general youth are being undertaken. Alongside prevention activities, gathering of data has been a key activity fostered by both the Government and individual development partners. This paper reviews available sources of data, including routine surveillance (HIV and behavioural among most at-risk populations), general population surveys, and various research studies with the aim to understand the dynamics of the HIV epidemic in Bangladesh. Available data show that the HIV epidemic is still at relatively low levels and is concentrated mainly among injecting drug users (IDUs) in Dhaka city. In addition, when the passively-reported cases were analyzed, another population group that appears to be especially vulnerable is migrant workers who leave their families and travel abroad for work. However, all sources of data confirm that risk behaviours that make individuals vulnerable to HIV are high--this is apparent within most at-risk populations and the general population (adult males and youth males and females). Based on the current activities and the sources of data, modelling exercises of the future of the HIV epidemic in Dhaka suggest that, if interventions are not enhanced further, Bangladesh is likely to start with an IDU-driven epidemic, similar to other neighbouring countries, which will then move to other population groups, including sex workers, males who have sex with males, clients of sex workers, and ultimately their families. This review reiterates the often repeated message that if Bangladesh wants to be an example of how to avert an HIV epidemic, it needs to act now using evidence-based programming.

Prevalencia de la coinfección virus de la inmunodeficiencia humana (VIH)- Trypanosoma cruzi e impacto del abuso de drogas inyectables en un centro de salud de la ciudad de Buenos Aires / Prevalence of human immunodeficiency virus (HIV)- Trypanosoma cruzi co-infection and injectable-drugs abuse in a Buenos Aires health center

Se evaluó la prevalencia de coinfección virus de la inmunodeficiencia humana (VIH)- Trypanosoma cruzi ( T. cruzi) en pacientes atendidos en un centro asistencial de Buenos Aires, Argentina. Se realizó un análisis retrospectivo de las historias clínicas de 602 individuos VIH positivos. Sólo en el 51,3% de estos pacientes se había investigado la presencia de T. cruzi. La prevalencia global de coinfección fue del 4,2%, siendo más elevada en usuarios de drogas inyectables (UDI) (8,9% vs. 2,6%, p<0,05). Sobre la base de estos resultados, concluimos que debería enfatizarse el cumplimiento de la indicación de diagnóstico para la enfermedad de Chagas en pacientes VIH positivos, especialmente en UDI.

The aim of this study was to evaluate the prevalence of human immunodeficiency virus (HIV)- Trypanosoma cruzi co-infection in a Buenos Aires health center. A retrospective analysis of the clinical charts of 602 HIV-infected patients was performed. Only 51.3% of the patients were evaluated against T. cruzi. The global co-infection prevalence was 4.2%, being more frequent among injectable drug users (IDU) (8.9% vs. 2.6%, p<0.05). The indication of T. cruzi testing should be stressed for HIV-infected patients, especially in those centers where IDU are assisted.

Multiple infections and associated risk factors among non-injecting cocaine users in Argentina

El propósito de este estudio era estimar los índices de seroprevalencia del virus de inmunodeficiencia humano (VIH), virus de la hepatitis B (VHB, anticuerpo core), virus de la hepatitis C (VHC) e infecciones de sífilis y analizar factores de riesgo asociados entre 504 usuarios de cocaína no inyectable (UCNI) en la ciudad de Buenos Aires, Argentina. Se entrevistó a los participantes en sesiones cara a cara a través de un cuestionario estructurado corto. Usando el método de la venipunción se recogieron 10mL de sangre. Las tasas de seroprevalencia fueron: VIH (6,3 por ciento), VHB (9 por ciento), VHC (7,5 por ciento), y VDRL (4,2 por ciento). El riesgo de infección por VIH, VHB, y VHC se asoció significativamente a mantener relaciones sexuales con un compañero/a que era consumidor de la droga inyectada o que era conocido por ser VIH positivo. Las infecciones de VIH y de VHC se asociaron a haber estado encarcelado anteriormente, y la de VHC se asoció también a haber sido tatuado. Debido al número creciente de UCNI y a las infecciones múltiples detectadas, es esencial implementar estrategias de prevención centradas en esta población.

The aim of this study was to estimate the seroprevalence rates of human immunodeficiency virus (HIV), hepatitis B virus (HBV, core antibody), hepatitis C virus (HCV), and syphilis infections and analyze associated risk factors among 504 non-injecting cocaine users (NICU) in Buenos Aires, Argentina. Participants were interviewed in face-to-face sessions through a short structured questionnaire. Using venipuncture, 10mL of blood was collected. Seroprevalence rates were: HIV (6.3 percent), HBV (9 percent), HCV (7.5 percent), and VDRL (4.2 percent). The risk of being infected with HIV, HBV, and HCV was significantly associated with having had a sex partner who was either a drug injector or who was known to be HIV positive. HIV and HCV infections were associated with former imprisonment, and HCV was associated with having been tattooed. Because of the rising number of NICU and the multiple infections detected, it is essential to implement prevention strategies focused on this population.

Prevalence of hepatitis C virus and HIV infection among injection drug users in two Mexican cities bordering the U. S

OBJECTIVE: To estimate the prevalence of the hepatitis C virus (HCV) and HIV infection and associated risk behaviors among injection drug users (IDUs) in two northern Mexican cities. MATERIAL AND METHODS: Between February and April 2005, IDUs were recruited in Tijuana (N=222) and Ciudad Juarez (N=206) using respondent-driven sampling (RDS), a chain referral sampling approach. Interviewer-administered questionnaires assessed drug-using behaviors during the prior six months. Venous blood was collected for immunoassays to detect HIV and HCV antibodies. For HIV, Western blot or immunofluorescence assay was used for confirmatory testing. Final HCV antibody prevalence was estimated using RDS adjustments. RESULTS: Overall, HCV and HIV prevalence was 96.0 percent and 2.8 percent, respectively, and was similar in both cities. Most IDUs (87.5 percent) reported passing on their used injection equipment to others, and 85.9 percent had received used equipment from others. CONCLUSIONS: HIV prevalence was relatively high given the prevalence of HIV in the general population, and HCV prevalence was extremely high among IDUs in Tijuana and Ciudad Juarez. Frequent sharing practices indicate a high potential for continued transmission for both infections. HCV counseling and testing for IDUs in Mexico and interventions to reduce sharing of injection equipment are needed.

OBJETIVO: Estimar las prevalencias de los virus de hepatitis C (VHC) y de VIH y los comportamientos de riesgo asociados con ellos, entre usuarios de drogas inyectables (UDI) en dos ciudades del norte de México. MATERIAL Y MÉTODOS: Entre febrero y abril de 2005, se reclutaron UDIs en Tijuana (N=222) y en Ciudad Juárez (N=206), mediante un método de muestreo llamado en inglés "respondent-driven sampling" (RDS), lo cual es un sistema basado en cadenas de referencia. Los participantes contestaron una encuesta aplicada por entrevista, la cual indagó acerca de los comportamientos en el uso de drogas durante los seis meses previos. Una muestra de sangre venosa fue colectada de cada individuo, para determinar la presencia de anticuerpos contra VIH y VHC mediante técnicas inmunoenzimáticas. En el caso del VIH la técnica de "Western blot" se aplicó con fines de confirmación. La prevalencia final de anticuerpos contra VHC se hizo mediante un cálculo ajustado, que empleó un estimador poblacional del RDS. RESULTADOS: Las seroprevalencias globales de VHC y VIH, fueron 96 por ciento y 2.8 por ciento, respectivamente. Estas frecuencias fueron similares entre las muestras de ambas ciudades. La gran mayoría de los UDI (87.5 por ciento) manifestó haber transferido a otros sus equipos de inyección usados y a su vez 85.9 por ciento de los participantes declaró haber recibido equipos usados de otros. CONCLUSIONES: La seroprevalencia encontrada de VIH fue relativamente alta dada la prevalencia de VIH en la población general y la de VHC fue extremadamente alta entre los UDI estudiados en Tijuana y en Ciudad Juárez. Las prácticas frecuentes de compartimiento de equipo señalan hacia un alto potencial que favorece la transmisión de ambas infecciones investigadas. Por tanto, son necesarias actividades de consejería y pruebas de laboratorio para VHC dirigidas a UDI en México y asimismo intervenciones para reducir el uso compartido de equipos de inyección.