High proportion of hepatitis C virus genotypes 1 and 3 in a large cohort of patients from Southern Brazil

PROFILE OF HCV GENOTYPES AND HIV-SUBTYPES AMONG HIV-COINFECTED PATIENTS IN SOUTHERN BRAZIL

BACKGROUND

Hepatitis B and C virus (HBV and HCV) are the two most common infections among human immunodeficiency virus (HIV)-infected patients.

OBJECTIVE

To identify the frequency of HIV subtypes and HCV genotypes in HIV-coinfected patients.

METHODS

A cross-sectional and retrospective study was carried out into two reference centers in Southern Brazil between January 1, 2002 and June 30, 2016. The Abbott Real Time HCV Genotype II system was used for routine diagnostics to determine the HCV genotype based on dual-target real-time PCR. Proviral HIV-1 RNA was extracted from serum samples and fragments of the pol gene were generated by PCR. The HIV-1 PT and RT gene sequences were submitted to Maximum Likelihood Phylogenetic analysis by collecting reference sequences from the HIV-1 group M subtype of the Los Alamos database.

RESULTS

During the study period, 3340 patients with HIV were diagnosed at both referral centers, of which 4.97% (166/3340) had HBV and/or HCV coinfection. Seroprevalence of HIV-HBV, HIV-HCV and HIV-HBV-HCV was 37.4%, 58.4%, and 4.2%, respectively. HIV-HCV-coinfected patients had a lower median nadir CD4+ T-cell count when compared to HIV-HBV-coinfected patients (P=0.01). Among those coinfected with HCV, HCV-1 (HCV-1) and HCV-3 (HCV-3) genotypes were the most prevalent, being detected in 73.8% and 21.4%, respectively. Among the HCV-1 coinfected patients, 79.3% and 20.1% had subtypes 1a and 1b, respectively. HIV subtype B was the most prevalent in HIV-coinfected patients. There was no significant difference regarding nadir CD4+ T-cell count and HIV viral load when compared to coinfected with HCV-1 with HCV-3, as well as those co-infected with HCV-1a with HCV-1b.

CONCLUSION

In the present study, a higher frequency of subtype B of HIV and HCV-1 were found in HIV-coinfected patients. Further larger-scale and long-term studies are needed to better understand the effect of HCV genotypes in HIV-infected patients.

Hepatitis C: evaluation of outcomes and georeferencing of cases in Santa Cruz do Sul, Brazil, between 2002 and 2015. A cross-sectional study

BACKGROUND

Hepatitis C virus infection is one of the main causes of chronic liver disease, with high death rates. The aim here was to analyze case outcomes, sociodemographic and clinical characteristics and spatial distribution among patients diagnosed with hepatitis C in the city of Santa Cruz do Sul (RS), Brazil.

DESIGN AND SETTING

Cross-sectional study on 200 cases of hepatitis C in Santa Cruz do Sul that were notified between 2002 and 2015.

METHODS

Secondary data including sociodemographic and clinical variables and type of outcome (death, follow-up, abandonment or clinical cure) were gathered. The spatial distribution analysis on hepatitis C virus cases according to outcome was based on information regarding residential address.

RESULTS

58.5% of the patients were 41 years of age and over, 67% were males and 92.5% had the chronic form of the disease. The most frequent transmission route was illicit drug injection (29%); 15.1% of the patients presented coinfection with the human immunodeficiency virus (HIV). Regarding outcomes, 31% achieved clinical cure, 10% died and 20% abandoned follow-up. The cases studied were mainly located in regions of the city characterized by lower socioeconomic status, with high frequency of places used for drug trafficking.

CONCLUSION

The population consisted of adults aged 41 years and over, mostly with chronic hepatitis C. The most common transmission routes were illicit drug injection and blood transfusions. There were high rates of HIV coinfection and abandonment of disease monitoring and predominance of cases in neighborhoods with low socioeconomic status.

Prevalence of hepatitis C virus and human immunodeficiency virus in a group of patients newly diagnosed with active tuberculosis in Porto Alegre, Southern Brazil

BACKGROUND

Porto Alegre is the Brazilian state capital with second highest incidence of tuberculosis (TB) and the highest proportion of people infected with human immunodeficiency virus (HIV) among patients with TB. Hepatitis C virus (HCV) infection increases the risk of anti-TB drug-induced hepatotoxicity, which may result in discontinuation of the therapy.

OBJECTIVES

The aim of this study was (i) to estimate prevalence of HCV and HIV in a group of patients newly diagnosed with active TB in a public reference hospital in Porto Alegre and (ii) to compare demographic, behavioural, and clinical characteristics of patients in relation to their HCV infection status.

METHODS

One hundred and thirty-eight patients with TB were tested for anti-HCV antibody, HCV RNA, and anti-HIV1/2 antibody markers. HCV RNA from real-time polymerase chain reaction (PCR)-positive samples was submitted to reverse transcription and PCR amplification. The 5′ non-coding region of the HCV genome was sequenced, and genotypes of HCV isolates were determined.

FINDINGS

Anti-HCV antibody, HCV RNA, and anti-HIV antibodies were detected in 27 [20%; 95% confidence interval (CI), 13-26%], 17 (12%; 95% CI, 7-18%), and 34 (25%; 95% CI, 17-32%) patients, respectively. HCV isolates belonged to genotypes 1 (n = 12) and 3 (n = 4). Some characteristics were significantly more frequent in patients infected with HCV. Among them, non-white individuals, alcoholics, users of illicit drugs, imprisoned individuals, and those with history of previous TB episode were more commonly infected with HCV (p < 0.05).

MAIN CONCLUSIONS

HCV screening, including detection of anti-HCV antibody and HCV RNA, will be important to improving the management of co-infected patients, given their increased risk of developing TB treatment-related hepatotoxicity.

Detection of hepatitis C virus in patients with terminal renal disease undergoing dialysis in southern Brazil: prevalence, risk factors, genotypes, and viral load dynamics in hemodialysis patients

Hepatitis C (HCV) is a serious public health issue, and it is estimated that 3% of the world's population is infected. Patients in hemodialysis units have an increased risk for contracting HCV, and high prevalence rates have been found in hemodialysis units around the world. This study is aimed at determining the prevalence of HCV in patients with terminal chronic renal disease (tCRD) who have been submitted to hemodialysis and peritoneal dialysis in southern Brazil to characterize the most prevalent genotypes, the viral load, and possible risk factors and to assess the validity between the ELISA and RT-PCR detection methods. Of 320 patients from three dialysis units, 318 participated in this study. According to the medical records, 55 patients were reactive to HCV, as determined via ELISA. All 318 samples were submitted to RT-PCR and genotyped using an Abbott Realtime m2000 system. Data obtained through a questionnaire and chemical variables were associated with the HCV.

RESULTS

The prevalence of HCV was 18.24% (58), and the concordance between the HCV serology and the RT-PCR was 94%. Three patients were diagnosed to be negative for HCV using the ELISA assay but positive when using RT-PCR. Genotype 1 was the most prevalent (46.7%) genotype, within which subtype 1a was the most frequent (74.1%). One of the risk factors associated with HCV infection was the length of time that the patient had been undergoing hemodialysis treatments (p < 0.001). Additionally, the viral load was found to vary when tested before and after hemodialysis (p < 0.001).

CONCLUSION

The prevalence of HCV in dialysis units continues to remain high, indicating nosocomial contamination. RT-PCR detected the presence of the hepatitis C virus in patients with a non-reactive serology, which highlights the importance of performing molecular tests on dialysis patients. The variation in the viral load in patients submitted to hemodialysis indicates a possible destruction or gripping of viral particles to the dialyzer membrane.

HIV and HCV coinfection: prevalence, associated factors and genotype characterization in the Midwest Region of Brazil

A cross-sectional study on prevalence, associated factors and genotype distribution of HCV infection was conducted among 848 HIV-infected patients recruited at reference centers in the Midwest Region of Brazil. The prevalence rate of HIV-HCV coinfection was 6.9% (95% CI: 5.2 to 8.6). In multivariable analysis, increasing age, use of illicit drugs (injection and non-injection), a history of blood transfusion before 1994, and the absence of a steady partnership were significant independent associated factors for HIV-HCV coinfection. The phylogenetic analysis based on the NS5B region revealed the presence of two major circulating genotypes of HCV: genotypes 1 (58.3%) and 3 (41.7%). The prevalence of HIV-HCV coinfection was lower than those reported in studies conducted with HIV-infected patients in different regions of Brazil, due to the fact that illicit drug use is not a frequent mode of HIV transmission in this region of Brazil. Serologic screening of HIV-patients for HCV before initiating antiretroviral treatment, a comprehensive identification of associated factors, and the implementation of effective harm reduction programs are highly recommended to provide useful information for treatment and to prevent HCV coinfection in these patients.

Evidence of association between hepatitis C virus genotype 2b and nosocomial transmissions in hemodialysis centers from southern Brazil

Background

Hepatitis C virus infection is a serious public health problem. Hemodialysis is considered one of the main risk factors of HCV infection, due to several invasive medical procedures and potential nosocomial transmission that patients with chronic renal failure (CRF) are continuously submitted. The aims of this study were to determine the prevalence of HCV and its genotypes in patients with CRF in hemodialysis units in southern Brazil.

Methods

Demographic data and risk factors for HCV transmission were collected and analyzed. These data were obtained from patients undergoing hemodialysis treatment from January 2009 to August 2010, on two dialysis units of Rio Grande, southern Brazil. Genotyping was carried out by sequencing analysis of HCV NS5b, core-E1 junction and 5′UTR genomic regions.

Results

One hundred fifty-nine patients under regular hemodialysis treatment were studied. HCV prevalence was 23.3%. HCV-infected patients had been on dialysis treatment for 91.9 months, a more prolonged period compared to HCV-negative patients (p = 0.001). While HCV genotypes 1b and 3a were identified as the most frequent strains, a surprisingly high proportion of genotype 2b was observed among patients in one of the dialysis centers compared to the general HCV-infected population of the same area. Hemodialysis treatment exposure time and healthcare working were associated with HCV infection.

Conclusions

Besides the efforts to minimize nosocomial transmission of HCV, some events of transmission are still evidenced in dialysis units.

Response to treatment in Brazilian patients with chronic hepatitis C is associated with a single-nucleotide polymorphism near the interleukin-28B gene

A single-nucleotide polymorphism (SNP) upstream of interleukin (IL)28B was recently identified as an important predictor of the outcome of chronic hepatitis C patients treated with pegylated interferon plus ribavirin (PEG-IFN/RBV). The aim of this study was to investigate the association between the IL28B gene polymorphism (rs12979860) and virological response in chronic hepatitis C patients. Brazilian patients (n = 263) who were infected with hepatitis C virus (HCV) genotype 1 and were receiving PEG-IFN/RBV were genotyped. Early virological response (EVR) (12 weeks), end-of-treatment response (EOTR) (48 weeks), sustained virological response (SVR) (72 weeks) and relapse were evaluated using conventional and quantitative polymerase chain reaction (PCR) assays. The frequency of the C allele in the population was 39%. Overall, 43% of patients experienced SVR. The IL28B CC genotype was significantly associated with higher treatment response rates and a lower relapse rate compared to the other genotypes [84% vs. 58% EVR, 92% vs. 63% EOTR, 76% vs. 38% SVR and 17% vs. 40% relapse rate in CC vs. other genotypes (CT and TT), respectively]. Thus, the IL28B genotype appears to be a strong predictor of SVR following PEG-IFN/RBV therapy in treatment-naïve Brazilian patients infected with HCV genotype 1. This study, together with similar research examining other SNPs, should help to define adequate protocols for the treatment of patients infected with HCV genotype 1, especially those with a poor prognosis.

Risk factors for infection with different hepatitis C virus genotypes in southern Brazil

Objectives. To investigate the proportion of different genotypes in countryside microregions in southern Brazil, and their association with risk factors. Methods. Cross-sectional study including a convenience sample of patients who tested positive for HCV-RNA and were referred to a regional health center for genotyping, from December 2003 to January 2008. Data were obtained through the National Disease Surveillance Data System, from laboratory registers and from patient charts. Identification of genotypes was carried out using the Restriction Fragment Length Polymorphism “in house” technique. Independent associations with genotypes were evaluated in multinomial logistic regression and prevalence rates of genotypes were estimated with modified Poisson regression. Results. The sample consisted of 441 individuals, 41.1 ± 12.0 years old, 56.5% men. Genotype 1 was observed in 41.5% (95% CI 37.9–48.1) of patients, genotype 2 in 19.3% (95% CI 15.0–23.6), and genotype 3 in 39.2% (95% CI 35.6–43.0). HCV genotype was significantly associated with gender and age. Dental procedures were associated with higher proportion of genotype 2 independently of age, education, and patient treatment center. Conclusions. The hepatitis C virus genotype 1 was the most frequent. Genotype 2 was associated with female gender, age, and dental procedure exposition.

Trends and projections of hepatitis C virus epidemiology in Latin America

BACKGROUND AND AIM

The purpose of the present investigation is to provide an analysis of previous works on the epidemiology of the hepatitis C virus (HCV) infection from six countries throughout Latin America, to forecast the future HCV prevalence trends in Argentina, Brazil, Mexico and Puerto Rico, and to outline deficiencies in available data, highlighting the need for further research.

METHODS

Data references were identified through indexed journals and non-indexed sources. Overall, 1080 articles were reviewed and 150 were selected based on their relevance to this work. When multiple data sources were available for a key assumption, a systematic process using multi-objective decision analysis (MODA) was used to select the most appropriate sources. When data were missing, analogues were used. Data from other countries with similar risk factors and/or population compositions were used as a proxy to help predict the future trends in prevalence.

RESULTS

The review indicates that the dominant genotype is type 1. HCV prevalence in the analysed countries ranges from 1 to 2.3%. The Latin American countries have been very proactive in screening their blood supplies, thus minimizing the risk of transmission through transfusion. This suggests that other risk factors are set to play a major role in continued new infections. The number of diagnosed and treated patients is low, thereby increasing the burden of complications such as liver cirrhosis or hepatocellular carcinoma. The HCV prevalence, according to our modelling is steady or increasing and the number of infected individuals will increase.

CONCLUSIONS

The results herein reported should provide a foundation for informed planning efforts to tackle hepatitis.

Genetic history of hepatitis C virus in Venezuela: high diversity and long time of evolution of HCV genotype 2

BACKGROUND

The subtype diversity of the hepatitis C virus (HCV) genotypes is unknown in Venezuela.

METHODOLOGY/PRINCIPAL FINDINGS

Partial sequencing of the NS5B region was performed in 310 isolates circulating in patients from 1995 to 2007. In the samples collected between 2005 and 2007, HCV genotype 1 (G1) was the most common genotype (63%), composed as expected of mainly G1a and G1b. G2 was the second most common genotype (33%), being G2a almost absent and G2j the most frequent subtype. Sequence analysis of the core region confirmed the subtype assignment performed within the NS5b region in 63 isolates. The complete genome sequence of G2j was obtained. G2j has been described in France, Canada and Burkina Fasso, but it was not found in Martinique, where several subtypes of G2 circulate in the general population. Bayesian coalescence analysis indicated a most recent common ancestor (MRCA) of G2j around 1785, before the introduction of G1b (1869) and G1a (1922). While HCV G1a and G1b experienced a growth reduction since 1990, coincident with the time when blood testing was implemented in Venezuela, HCV G2j did not seem to reach growth equilibrium during this period.

CONCLUSIONS/SIGNIFICANCE

Assuming the introduction of G2j from Africa during the slave trade, the high frequency of G2j found in Venezuela could suggest: 1- the introduction of African ethnic groups different from the ones introduced to Martinique or 2- the occurrence of a founder effect. This study represents an in-depth analysis of the subtype diversity of HCV in Venezuela, which is still unexplored in the Americas and deserves further studies.

An overview about hepatitis C: a devastating virus

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.

Molecular epidemiology of hepatitis C virus genotypes in west Mexico

The identification of hepatitis C virus (HCV) genotypes and subtypes may be helpful to identify the source of an HCV outbreak among a specific group of individuals within a given country or the pattern of spread throughout nations worldwide. Mexico is a transit country for people who migrate north towards the United States from Central and South America, however, to date, no Mexican HCV sequences have been reported. The present study was conducted to identify the HCV genotypes and subtypes prevalent in Mexico by DNA sequencing and phylogenetic analysis in the NS5B region of the HCV genome. Serum samples from a total of 75 anti-HCV positive patients were included in this study. Out of the 75 samples, 48 cases (64%) were amplifiable in the 5' UTR and 46 (61%) in NS5B region. HCV genotype 1a determined in 54.3% (25/46) was predominant in this cohort, followed by 1b 21.8% (10/46), 2b 13% (6/46), 3a 6.5% (3/46), and 2a 4.4% (2/46). Phylogenetic analysis showed that HCV sequences of genotype 1 (1a and 1b) were clustering more closely to the United States isolates published previously. These results may suggest that both Mexico and the United States share an epidemiological network of HCV genotype 1 while other genotypes represent sporadic infections that are specific to Mexico.

Colorimetric microwell plate reverse-hybridization assay for detection and genotyping of hepatitis C virus

This study describes a colorimetric method for detecting and genotyping hepatitis C virus (HCV) in which four different oligonucleotide probes are fixed onto microwell plates and hybridized separately with biotinylated PCR amplification products derived from clinical samples. The first probe capable of hybridizing with all seven known HCV genotypes was used for overall detection, and the remaining probes were used to recognize specifically genotypes 1-3. When combined with an improved silica-based RNA extraction method, the sensitivity of the test was 50 IU/mL. Eighty-five of the 86 samples analyzed (98.8%) yielded results in agreement with reference detection methods. The remaining sample was HCV-RNA positive in the COBAS Amplicor qualitative assay, but was negative using the reverse-hybridization method. The usefulness of the new genotyping test was confirmed by comparison with direct sequencing of PCR products: 98% of samples tested (54/55) were in agreement using the two methods (21, 7 and 27 from genotypes 1-3, respectively). The single discrepancy might have been due to a mixed HCV infection. The new method is an alternative to the use of commercially available genotyping kits and should be particularly convenient in developing countries where genotypes 1-3 represent a high proportion of HCV isolates.

Genetic variability in the 5' UTR and NS5A regions of hepatitis C virus RNA isolated from non-responding and responding patients with chronic HCV genotype 1 infection

Sequence variation among different hepatitis C virus (HCV) isolates has adaptive significance and reflects the modes and intensities of selection mechanisms operating on the virus. In this work, we sought to investigate using classical population genetics parameters, the genetic variability of HCV genotype 1 using the 5' UTR and NS5A regions from treatment non-responding and responding groups of patients. Both regions showed low genetic variability and the 5' UTR showed neutral deviation. No differences were observed in the nonsynonymous/synonymous nucleotide substitution ratio among groups for NS5A. The analysis of molecular variance test of the 5' UTR region showed an 11.94% variation among groups. Phylogenetic analysis showed no correlation between sequence variations and therapeutic responses.

Molecular and contextual markers of hepatitis C virus and drug abuse

The spread of hepatitis C virus (HCV) infection involves a complex interplay of social risks, and molecular factors of both virus and host. Injection drug abuse is the most powerful risk factor for HCV infection, followed by sexual transmission and additional non-injection drug abuse factors such as co-infection with other viruses and barriers to treatment. It is clearly important to understand the wider context in which the factors related to HCV infection occur. This understanding is required for a comprehensive approach leading to the successful prevention, diagnosis, and treatment of HCV. An additional consideration is that current treatments and advanced molecular methods are generally unavailable to socially disadvantaged patients. Thus, the recognition of behavioral/social, viral, and host factors as components of an integrated approach to HCV is important to help this vulnerable group. Equally important, this approach is key to the development of personalized patient treatment - a significant goal in global healthcare. In this review, we discuss recent findings concerning the impact of drug abuse, epidemiology, social behavior, virology, immunopathology, and genetics on HCV infection and the course of disease.