Hepatitis C virus infection status and associated factors among a multi-site sample of people who used illicit drugs in the Amazon region

Abstract

Background Elevated rates of Hepatitis C Virus (HCV) infection have been reported in epidemiological studies with people who used illicit drugs (PWUIDs) in different Brazilian regions. In Brazil’s Amazon region, studies have already identified the common use of illicit drugs among adolescents and the high prevalence of HCV infections among PWUIDs. However, all studies done with PWUIDs were conducted with small samples and within limited geographic coverage. This study determined the prevalence and risk factors for HCV infection in PWUIDs in the Amazon region, northern Brazil, as well as estimating the prevalence and factors associated with the HCV spontaneous clearance (HSC). Methods This cross-sectional study accessed 1666 PWUIDs from multiple municipalities of the Amazon region. Socio-demographic, economic, drug use and health-related information were collected through interviews. Blood samples collected were tested for the presence of anti-HCV antibodies and RNA-HCV. HCV genotypes were identified by real-time polymerase chain reaction (PCR). Logistic regressions were run to identify factors independently associated with HCV infection status and HSC. Results In total, 577 (34.6%) featured HCV antibodies, of which 384 (23.1%) had active HCV infection and 193 (11.6%) indicated HSC. Genotypes 1 (80.2%) and 3 (18.8%) were detected. HCV infection status was associated with the length of illicit drug use history, factors related to parenteral and sexual transmission, and factors of socio-economic marginalization leading to potential risk activities for HCV. HSC was associated with the ethnic (including indigenous) background of participants. Conclusions High levels of HCV infection were detected in PWUIDs. Genotype 1 was predominant. Intense use of illicit drugs, unprotected sexual intercourse, high number of sexual partners and social marginalization were associated with all HCV infection. HSC was associated with origin (Amazonian-born) and non-white (e.g., Black or Indigenous) of PWUIDs. These findings emphasize the need for improve HCV prevention and control services and care for PWUIDs in the Brazilian Amazon region. Electronic supplementary material The online version of this article (10.1186/s12879-019-4270-2) contains supplementary material, which is available to authorized users.

Hepatitis C Virus among Female Sex Workers: A Cross-Sectional Study Conducted along Rivers and Highways in the Amazon Region

“…In the Amazon region, the estimated prevalence of HCV infection ranges from 1% to 3%, with higher rates being recorded in vulnerable groups, such as PWUDs (23.1%), patients undergoing hemodialysis (8.4%), and patients with hemophilia (48.4%) [5,[20][21][22][23][24]29,36,46]. The prevalence of HCV infection detected in this study was 10.7%, and most of these infections were classified as active (7.8%).…”

“…In this study, there was a predominance of genotype 1 (81.3%), especially subtypes 1a (34.4%) and 1b (46.9%), with the presence of RASs in antiviral therapy-naive FSWs. Historically, epidemiological studies conducted in the Amazon region have indicated the predominance of HCV genotype 1 but without an evaluation of the presence of RASs [5,18,20,36]. Studies conducted in other Brazilian regions reported the presence of genetic variants in chronic HCV-infected patients and not treated with DAAs, which may vary from 3.2% to 18.9% [19,[58][59][60].…”

“…Currently, illicit drug use is a major risk factor for HCV infection [2,3]. Risky sexual behavior may also be a risk factor for HCV infection, and has been reported as an important route of viral transmission among people who use illicit drugs (PWUDs), female sex workers (FSWs), and men who have sex with other men (MSMs) [5][6][7].…”

“…In the Amazon region (northern Brazil), several epidemiological studies indicate a high prevalence of HCV infections and the predominance of genotype 1 in different population groups, such as indigenous people, people living in riverside communities, blood donors, patients undergoing hemodialysis, patients with multiple blood transfusions, and PWUDs [5,18,[20][21][22][23][24][25]. Factors associated with parenteral and sexual exposure to HCV have been detected, including: Shared use of manicure and pedicure instruments, use of home-sterilized needles and syringes, unprotected sexual intercourse, more than 12 sexual partners, daily drug use, drug use for more than three years, and shared use of drug paraphernalia [5,[26][27][28][29]. However, much of the epidemiological information on HCV infection among other vulnerable groups in the Amazon region, such as FSWs, is still unknown.…”

Prevalence of syphilis in female sex workers in three countryside cities of the state of Pará, Brazilian Amazon

“…This study is one of the first epidemiological reports on syphilis in FSWs in the Brazilian Amazon region. In this region, the Amazon rainforest occupies large areas of the northern Brazil, which causes relative isolation, resulting (or because of) limited infrastructure and public services and low human development [11]. This scenario has a negative impact on sexual behaviour, increasing risk-taking activities [12][13][14].…”