Mode of hepatitis C virus infection, epidemiology, and chronicity rate in the general population and risk groups

Prevalence of hepatitis C infection in Iranian hemodialysis patients: An updated systematic review and meta-analysis

BACKGROUND

Hepatitis C virus (HCV) is a major cause of liver disease and a potential cause of substantial morbidity and mortality. This study aims to provide a comprehensive evidence on HCV Infection in Iranian hemodialysis (HD) patients we conducted a systematic review.

MATERIALS AND METHODS

In this systematic review and meta-analysis, through a comprehensive search of literature until January of 2016, we estimated the pooled prevalence of hepatitis C infection in Iranian HD patients. Using Medical Subject Headings terms, Emtree, and related equal Persian key words for Iranian databases and also international databases of PubMed and NLM Gateway (for MEDLINE), and SCOPUS. Interest outcome of HCV infection prevalence was confirmed based on positive hepatitis B surface antigen of blood samples. Random effect meta-analysis was used to estimate pooled prevalence of HCV infection in Iranian HD patients, date and language, HD patients, in adult HD patients, Institute of Scientific Information, Iran-doc, irrespective of age, living in Iran. Searches run through main domestic databanks of Iran-Medex, renal transplantation, Scientific Information Database, the relevant literature-searched concentrating on HCV infection.

RESULTS

Through searching steps, 305 publications were found from them following the excluding duplicates and overlapping studies 54 studies relevant to HCV prevalence in Iranian HD zcxw patients, with number of 23921 participants, remained in our analyses. The overall results of test of heterogeneity demonstrate sever heterogeneity between reported prevalence (I2 = 96.62%, Chi-square = 1566, P < 0.001). Due to sever heterogeneity results of random effect meta-analysis showed that the estimated pooled prevalence was 11% (95% confidence interval [CI] =10%-13%). The pooled prevalence base on polymerase-chain reaction, recombinant immunoblot assay, and enzyme-Linked Immunosorbant Antibody method were 11% (95% CI = 6%-15%), 9% (95% CI = 5-13) and 12% (95% CI = 10-14), respectively. In line with previous studies, the present finding shows the significant variation in the rate of HCV in dialysis units among the regions in Iran.

CONCLUSION

Present paper is the comprehensive updated systematic review on HCV prevalence in the Iranian HD patients. Our findings provide the reliable evidence for promotion of policies and interventional programs.

Risk factor analysis of hepatitis C virus seropositivity in Iranian blood donors: a case-control study

BACKGROUND

Due to blood screening and blood donor selection, the prevalence of hepatitis C virus (HCV) is expected to be lower among blood donors compared to the general population. The effective control of blood-transmitted infectious diseases should be one of the goals of public health. Thus, this case-control study was conducted to evaluate the risk factors of HCV in a representative sample of blood donors in Iran.

STUDY DESIGN AND METHODS

A case-control study was conducted on HCV-negative and on serologically confirmed HCV-positive donors across the country from 2009 to 2013. Univariate logistic regression, multiple logistic regression, and subgroup analyses were performed to assess the risk factors in first-time blood donors (FTs) and repeat blood donors (RDs) independently.

RESULTS

A total of 970 cases and 1542 controls were selected from the cohort of Iranian blood donors registered in the Iran Blood Transfusion Organization. Intravenous (IV) drug abuse (ORFT , 6.42; 95% CI, 3.34-12.34; and ORRD , 27.62; 95% CI, 12.58-60.62), living with an IV drug abuser (ORFT , 3.47; 95% CI, 1.26-9.55; and ORRD , 6.95; 95% CI, 1.54-31.34), prison history (ORFT , 2.4; 95% CI, 1.48-3.88; and ORRD , 2.42; 95% CI, 1.38-4.27), sharing personal razors (ORFT , 2.00; 95% CI, 1.01-3.96; and ORRD , 5.62; 95% CI, 2.65-11.89), and medical exposure (ORFT , 1.97; 95% CI, 1.15-3.37; and ORRD , 2.19; 95% CI, 1.27-3.76) were significant independent risk factors in both types of blood donation.

CONCLUSION

The findings of this analytic study on HCV exposure in Iranian blood donors conforms to those of international studies. Behavioral and medical factors should be examined in the donor health screening process.

Prevalence of hepatitis C virus infection in patients with COPD

Some studies have suggested that chronic hepatitis C virus (HCV) infection may induce an accelerated decline of forced expiratory volume in 1 second (FEV1). We performed a cross-sectional study to determine the prevalence of HCV infection in a sample of chronic obstructive pulmonary disease (COPD) patients and in a control group of blood donors. The clinical characteristics of HCV-positive and HCV-negative patients were compared. Anti-HCV antibody was determined and confirmed by HCV-RNA. The prevalence of HCV infection in COPD patients was 7·5% (95% CI 6·52–8·48) and in blood donors was 0·41% (95% CI 0·40–0·42). The HCV-positive patients had a lower FEV1 (34·7±8·6%) and a higher BODE index (median=6) than HCV-negative patients (42·7±16·5%, median=4, respectively) (P=0·011 and 0·027, respectively). Our results suggest a high prevalence of chronic HCV infection in patients with COPD in comparison with the blood donors. HCV-positive patients have a more severe disease.

Hepatitis C infection in risk groups

Hepatitis C infection is important global health problem with wide spectrum of health, social and economic consequences. The goal of this research was to estimate prevalence of hepatitis C virus infection in risk groups, and to determine association hepatitis C virus (HCV) infection and risk factors. Research included 4627 subjects divided in two groups. Test group included 2627 subjects divided in 4 subgroups with risk for HCV infection: those who received blood transfusion without screening on HCV (it was introduced in 1995) (700); intravenous drug users (60); patients on hemodialysis (168) and health care workers (1699). Control group included 2000 healthy volunteer blood donors. In all subjects anti-HCV antibodies were tested with third generation ELISA test. Positive serum samples were tested for presence of HCVRNA, using reaction of reverse transcription and polymerase chain reaction. In all anti-HCV positive subjects further epidemiological and clinical workup was performed. Prevalence of HCV infection in risk groups was: 4.6% in subjects who have received blood transfusions without HCV blood screening, 35% in intravenous drug users, 58.9% in patients on chronic dialysis, and 0.4% in health care workers. In control group prevalence was low (0.2%). In the group of 158 anti-HCV positive subjects, 73.4% had HCVRNA. The largest number of subjects with HCV infection was in the age group of 30-49 years (45.8%). This study showed that multiple blood transfusions before introducing the blood screening for HCV, longer duration of intravenous drug abuse, longer duration of hemodialysis treatment, larger number of accidental injuries in health care workers are independent and statistically significant risk factors for those groups examined. Results of this study confirm that general screening for HCV infection is recommended in risk groups for HCV infection in order to identify to prevent and to treat it.

Hepatitis C virus transmission and its risk factors within families of patients infected with hepatitis C virus in southern Iran: Khuzestan

AIM: To determine whether hepatitis C virus (HCV) infection of index cases increases intrafamilial transmission (sexual and nonsexual contacts) of HCV.

METHODS: In a case-control descriptive study we enrolled 300-household contacts of 60 index cases (40 males and 20 females) of HCV infection and 360 pair-matched controls in Ahwaz JundiShapour University Hospitals from August 1, 1998 to September 1, 2003. The control group consisted of first time blood donors referred to the Regional Blood Transfusion Organization. Serum samples and demographic data and a medical history including the existence of risk factors for HCV (after a questionnaire on the risk factors for parenteral exposure) were obtained from each subject. Antibodies to HCV were detected employing a commercially available second-generation enzyme immunoassay (EIA, Abbott II). Positive serum specimens were retested using a second-generation recombinant immunoblot assay (RIBA-2) and a polymerase chain reaction for HCV RNA. Data analysis was carried out for intra-household clustering.

RESULTS: Only 4 of 300 (1.33%) cases of household contacts without percutaneous risk factors were positive for HCV Ab while the remaining 296 family contacts were negative for anti-HCV. The mean age of the index cases was 28.4 (Std 15.22) years. The anti-HCV prevalences in parents, spouses, children of the index cases were 0.87% (1/115), 3.39% (2/59)) and 0.79% (1/126), respectively. Among couple partners negative for anti-HCV antibodies, the mean duration of the sexual relationship was 6 years. The two-couple partners positive for anti-HCV antibodies married the index cases for longer than 15 years. The prevalence of positive HCV Ab among household contacts (1.33%) was not significantly higher than that in the controls (1%) (P > 0.06).

CONCLUSION: Intrafamilial transmission of HCV is not the significant transmission route and sexual transmission does not seem to play a role in the intrafamilial spread of HCV infection. Intrafamilial transmission of HCV is possible but occurs at a low rate.

Prevalence of antibodies against hepatitis C virus among blood donors in Lebanon, 1997-2000

Chronic hepatitis C virus (HCV) infection in many individuals is asymptomatic and the prevalence of antibodies to hepatitis C virus (anti-HCV) among blood donors in Lebanon is scarce. This study aimed to address the prevalence of anti-HCV in 8700 blood donors, the data obtained was compared to other world regions. Between 1997 and 2000, 8700 blood donors were screened for the presence of anti-HCV in their sera. Initially reactive specimens were retested in duplicate, and repeatedly positive samples were subsequently retested by a third generation microplate enzyme immunoassay. Of the 8700 blood donors screened, 51 were confirmed positive for anti-HCV, giving a prevalence rate of 0.6%. While there was no difference in anti-HCV prevalence in relation to age or gender, higher rates were seen in non-Lebanese compared to Lebanese subjects (6.17% vs. 0.48%, P < 0.001). None of the anti-HCV positive individuals had an identifiable risk factor for contracting HCV (intravenous drug user, prior transfusion, etc.), and their transaminases were comparable to anti-HCV-negative donors, suggesting that HCV-positive donors were asymptomatic. These results demonstrate low prevalence of anti-HCV among Lebanese blood donors, which was comparable to those established for Western countries.

Risk factors for hepatitis C virus infection in male adults in Rawalpindi-Islamabad, Pakistan

OBJECTIVE

To identify risk factors associated with HCV infection in Islamabad-Rawalpindi.

METHODS

Fifty-seven cases and 180 controls were enrolled from various departments of the nine major hospitals of the Rawalpindi-Islamabad during July-September 1998. Cases were enzyme-linked immunosorbent assay (ELISA) positive for antibodies to HCV (anti-HCV), aged 20-70 years, and residents of Islamabad or Rawalpindi division. Controls were anti-HCV ELISA negatives of the same age range and from the same area. A structured questionnaire was used to collect data on demographic variables and potential risk factors, which was analysed by logistic regression to calculate crude and adjusted odds ratios (OR) and corresponding 95% confidence intervals (CI) for risk factors.

RESULTS

The final multivariate logistic regression model revealed that after adjusting for age, cases were more likely to have received therapeutic injections in the past 10 years (1-10 vs. 0 therapeutic injections; adjusted OR=2.8, 95% CI: 1.1-7.1; > 10 vs. 0 therapeutic injections; adjusted OR=3.1, 95% CI: 1.2-7.9) and were significantly more likely to have daily face (adjusted OR=5.1, 95% CI: 1.5-17.0) and armpit shaves (adjusted OR=2.9, 95% CI: 1.3-6.5) by a barber.

CONCLUSION

HCV control and prevention programs in this region should include safe injection practices and educate men about the risk of HCV infection from contaminated instruments used by barbers.

Low frequency of HLA-DRB1*11 in hepatitis C virus induced end stage liver disease

Hepatitis C virus (HCV) infection becomes chronic in more than 70% of patients, leading to end stage liver disease in about 20-30% of these patients. Apart from the virus itself, host factors that modulate the immune response are likely to be involved in determining the outcome of HCV infection. Studies on the association of human leucocyte antigens (HLAs) and HCV infection have shown inconsistent results. Selection of patient subgroups may be crucial. However, any association relevant to HCV disease progression will become evident, especially in those patients with end stage liver disease. Therefore, we analysed the phenotype frequencies of HLA antigens in two groups of 69 and 39 patients with HCV induced liver cirrhosis who had received a transplant or were awaiting liver transplantation. The first group was typed serologically and compared with 331 blood and liver donors. The second group, prospectively HLA typed by a polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) procedure for HLA-DRB and DQB alleles, was compared with another 170 PCR-SSO typed and randomly selected blood donors. Decreased frequencies for HLA-DR5 and HLA-DQ3 were found in one group of patients with HCV induced liver cirrhosis compared with the control groups. In the second analysis comparing 39 patients with end stage liver cirrhosis with blood donors, we confirmed the significant decrease in HLA-DRB1*11 and HLA-DQB1*03, which corresponded to serological HLA-DR5 and HLA-DQ3 antigens, respectively. Our results show that the presence of HLA-DRB1*11 and HLA-DQB1*03 alleles is associated with a reduced risk for the development of HCV induced end stage liver disease.

Seroprevalence of hepatitis C in a sample of middle class substance abusers

Hepatitis C (HCV) is an indolent and often fatal disease affecting four million Americans commonly associated with low socioeconomic status. We assessed its prevalence in a sample of 334 consecutively admitted middle class substance abusers in a private urban hospital, and ascertained risk factors for its transmission. We found that the point prevalence rate for HCV was 27.7% among all substance abusers, and 76.7% among intravenous drug users. Using logistic regression, we found risk factors associated with HCV were intravenous drug use, needle sharing, prior liver disease, opioid dependence, HIV infection, and benzodiazepine dependence. Not found to increase infective risk were lower social class, male gender, African-American race, male homosexuality, unemployment, and the absence of private health insurance. Multiple viral genotype types were identified in this sample, suggesting diverse sources of transmission in the sample. This study documents an epidemic of HCV in an American middle class sample.

Independent expression of serological markers of thyroid autoimmunity and hepatitis virus C infection in the general population: results of a community-based study in north-western Sardinia

To assess the relationship between serological markers of thyroid autoimmunity and chronic hepatitis C, we surveyed the general population of two villages in the region of Sardinia, Italy, where infection with hepatitis viruses is endemic and the prevalence of autoimmune diseases is elevated. A total of 1310 subjects aged 6-88 years (65% of the total resident population) participated in the survey, and 1233 (94%; 444 males and 789 females) agreed to provide a blood sample. Autoantibodies to thyroid peroxidase (anti-TPO) were measured by radioimmunoassay; antibodies to HCV (anti-HCV) by a third generation enzyme immunoassay and borderline positive results confirmed by recombinant immunoblot assay. For both anti-HCV and anti-TPO the age- and gender-standardized prevalence rates (SPR) were calculated and the significance of the association between the two antibodies tested by Yates corrected chi2 test. The overall SPR for anti-HCV was 50.7x10(-3) (86/1,233), similar between men [49.1x10(-3) (22/444)] and women [52.3x10(-3) (64/789)]. The overall SPR for anti-TPO was 136.9x10(-3) (204/1,233), and that among women [201x10(-3) (174/789)] was almost 3-fold that among men [71.6x10(-3) (30/444)]. A concurrent anti-HCV and anti-TPO positivity was found in a small minority of subjects [8/1,233 (0.65%)], all women aged 57-81 years. The SPR for the two concurrent events was 3.3x10(-3), which was not significantly different (Yates corrected chi2 test = 0.65) from that expected under the assumption of unrelated events. To explore whether HCV infection is a risk factor for anti-TPO positivity, we designed a case-control study with anti-TPO positive subjects as the cases, and anti-TPO negative subjects as the controls. The age- and gender-adjusted odd ratio (OR) was 0.4 (95% CI 0.2,0.7), indicating a negative association. In conclusion, no evidence for epidemiological association of circulating thyroid autoantibodies and antibodies to HCV was found. Our findings do not therefore support a pathogenetic link between HCV infection and thyroid autoimmunity.

HCV genotypes in Northern Italy: a survey of 1368 histologically proven chronic hepatitis C patients

BACKGROUND/AIMS

Hepatitis C virus (HCV) easily undergoes genomic changes, thus accounting for the presence of different genotypes, with different geographic distributions and different outcomes of chronic hepatitis. Type 1b is frequently found in advanced diseases; however, since this genotype is the most prevalent in older patients, the association with advanced age and severity of the disease is confounding. The aim of this study was to assess changes in the prevalence of HCV genotypes by surveying a large population of chronic hepatitis C patients in Northern Italy, and to assess if the high prevalence of genotype 1b in older patients with advanced diseases simply reflects the duration of HCV infection, rather than intrinsic biological properties of HCV.

METHODS

We studied 1368 HCV-RNA positive patients, with histologically proven chronic hepatitis. Drug addiction, blood transfusions and sporadically acquired infections represented the risk factors.

RESULTS

Genotype 1b, the most prevalent isolate, and genotype 2a were associated with older age, cirrhosis, sporadically-acquired infections and blood transfusion, while types 1a, 3a, and 4 were associated with younger age, chronic persistent hepatitis and drug addiction. Patients with a history of transfusions were divided into four groups depending on the period of transfusion. The prevalence of genotype 1b decreased with time. Type 3a appeared only after 1979.

CONCLUSION

The severity of chronic hepatitis C could be related more to the duration of the infection rather than to the intrinsic pathogenicity of HCV genotypes.

[Molecular biology and transfusional viral safety]

In this review we present four fields to which viral molecular biology has contributed: the discovery of blood-borne viruses and the knowledge of the natural history of infection by these viruses; the validation of the results of virological assays used in the biological screening of blood donations; the contribution of molecular biology in inquiries into viral transfusional contamination; the interest of molecular biology in viral transfusional epidemiology. We subsequently deal with the parameters of the discussion on the impact and the feasibility of a systematic screening of several viral genomes in blood donations.