Epidemiological and genetic analyses of Hepatitis C virus transmission among young/short- and long-term injecting drug users from Rio de Janeiro, Brazil
Introduction
Worldwide, Hepatitis C Virus (HCV) infection is a public health challenge, due to its health and economical impacts.1 About 60–85% of infected-subjects develop chronic infection, of which major complications are liver cirrhosis and hepatocarcinoma.2
In the last decades, HCV epidemiology has been changing in developed countries, due to improved blood transfusion safety and better healthcare conditions. Consequently, injection drug use became the main mode of viral transmission and accounts for more than 60% of prevalent cases in Europe.3
Drug injectors are frequently engaged into risky behaviours,4, 5, 6 favouring an extensive HCV spread throughout IDUs networks.7 Many new infections occur in young/new IDU, among whom incidence rates from 11.6 to 37.3/100 persons-year have been described.8, 9
HCV is classified into six major genotypes and several subtypes,10 which present distinct geographical patterns and response to antiviral therapy.11 Moreover, a relationship between viral variants and mode of transmission has been shown.12, 13 Changing patterns/introduction of new subtypes can ensue relatively fast within IDU networks.3
In this study, practices and behaviours and their putative association with HCV infection/genotypes were investigated among young/short- and long-term IDUs. Phylogenetic relationships between IDU sequences and the extent of transmission between both subsets were also analyzed. This information is unavailable in Brazil, although critical to avert harmful practices among initiates.
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Population
From 1999 to 2001, 606 IDUs were recruited in the Rio de Janeiro's “drug scenes”, as previously described.14 After signing an informed consent, volunteers were interviewed using a structured questionnaire standardized by the World Health Organization (WHO)15 and a blood sample was collected.
All interviewees received pre-/post-test counselling and were referred to Health Services, if viral RNA-positive. HBV vaccination was also available. The study was approved by the Oswaldo Cruz Foundation's
Epidemiological findings
Socio-demographic features, drug use and sexual behaviours and HCV infection/viral genotypes prevalence among short-and long-term injectors are shown in Table 1. Two-hundred ninety nine and 307 interviewees were grouped as short- and long-term injectors, with a mean duration of injection of 2.2 vs.16.1 years (p < .001) and a median year of first injection of 1997 vs. 1986 (p < .001), respectively. ST were significantly younger and more likely to be single, compared to their counterparts. About half
Discussion
In this study, epidemiological and molecular patterns of HCV transmission among short- and long-term IDUs were assessed. These are pivotal information to provide the basis for sound preventive policies, management and care of such population.
Despite the efforts to obtain a representative sample of Rio de Janeiro's drug scenes, findings cannot be generalized to the IDU population. Moreover, as prevalence of HCV infection was significantly lower than expected, for some variables, a tiny sample
Conflict of interest
None.
Acknowledgments
This paper is based on the data and experience obtained during the WHO Drug Injection Study Phase II—a project, coordinated and sponsored by the World Health Organization and implemented by the WHO Phase II Drug Injection Collaborative Study Group. The authors alone are responsible for the views expressed in this paper, which do not necessarily represent those of the other investigators participating in the WHO Drug Injection Study Phase II nor the views or policy of the World Health
References (42)
- et al.
Scope of worldwide hepatitis C problem
Liver Transpl
(2003) - et al.
The changing epidemiology of hepatitis C virus infection in Europe
J Hepatol
(2008) - et al.
Prevalence and correlates of indirect sharing practices among young adult injection drug users in five U.S. cities
Drug Alcohol Depend
(2007) - et al.
Opportunities for prevention: hepatitis C prevalence and incidence in a cohort of young injection drug users
Hepatology
(2002) - et al.
High hepatitis C incidence in new injecting drug users: a policy failure
Aust N Z J Public Health
(2007) - et al.
Drug and alcohol consumption and sexual risk behaviour among young adults: results from a national survey
Drug Alcohol Depend
(1999) - National Institutes of Health;1;. National Institutes of Health Consensus Development Statement: management of...
- et al.
Frontloading: a risk factor for HIV and hepatitis C virus infection among injecting drug users in Berlin
AIDS
(1996) - et al.
Sharing of drug preparation equipment as a risk factor for hepatitis C
Am J Public Health
(2001) - Wiessing L, Roy K, Sapinho D, Hay G, Taylor A, Goldberg D et al. Surveillance of hepatitis C infection among injecting...
virus infection among injection drug users: survival analysis of time to seroconversion
Epidemiology
Classification of hepatitis C virus into six major genotypes and a series of subtypes by phylogenetic analysis of NS-5 region
J Gen Virol
Genetic diversity and evolution of hepatitis C virus-15 years on
J Gen Virol
Distribution of HCV genotypes among different exposure categories in Brazil
Braz J Med Biol Res
Molecular epidemiology of hepatitis C among drug users in Flanders, Belgium: association of genotype with clinical parameters and with sex- and drug-related risk behaviours
Eur J Clin Microbiol Infect Dis
WHO Phase II drug injection collaborative study group. Using standardized methods for research on HIV and injecting drug use in developing/transitional countries: case study from the WHO drug injection study Phase II
BMC Public Health
The role of “long-term” and “new” injectors in a declining HIV/AIDS epidemic in Rio de Janeiro
Brazil Subst Use Misuse
Differences in HCV antibody patterns in haemodialysis patients infected with the same virus isolate
J Med Virol
Hepatitis C virus genotyping: interrogation of the 5′ untranslated region cannot accurately distinguish genotypes 1a and 1b
J Clin Microbiol
A comprehensive system for consistent numbering of HCV sequences, proteins and epitopes
Hepatology
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