Usefulness and limitation of phylogenetic analysis for hepatitis C virus core region: application to isolates from Egyptian and Yemeni patients

Factors Affecting the Virological Response Among Chronic Hepatitis C Virus Patients in Yemen

Hepatitis C virus (HCV) infection is increasingly seen as a major public health problem, threat, and concern worldwide. In Yemen about 1.7% of the population is infected with chronic hepatitis C. This study aimed to detect the predictors for response to pegylated interferon and ribavirin (Peg-IFN/RBV) in chronic HCV Yemeni patients. The study was conducted on 100 patients with chronic HCV who received Peg-IFN/RBV in the 48th Military Hospital in Sana'a Yemen, from 2011 to 2013. All patients were subjected to complete history taking, thorough clinical examinations, routine laboratory investigation, and abdominal ultrasonography. The HCV RNA was assessed at week 72 of treatment to detect whether the patient achieved sustained virological response (SVR). The SVR was achieved in 64% of the samples. Age above 40, Khat chewing, and obesity were the sociodemographic factors that predict good response for Peg-IFN/RBV combined therapy. Platelet count, alpha feto-protein (AFP), aspartate transaminase (AST), and alanine transaminase (ALT) levels were the basic laboratory investigations that gave favorable response. Significant predictors of sustained response included: older than 40 years (OR = 0.136, P = 0.042), Khat chewer (OR = 0.016, P = 0.008), body mass index (BMI) (OR = 0.055, P = 0.029) and increase in fasting blood glucose (OR = 0.925, P = 0.004), alkaline phosphatase (OR = 0.969, P = 0.001), total and bilirubin (OR = 0.058, P = 0.017), AST (OR = 1.033, P = 0.002), and albumin (OR = 6.490, P = 0.021). Studying the independent variables of response, we revealed that male gender, BMI, ALT >40, AFP >10, viremia >600, and hemoglobin and thyroid stimulating hormone (TSH) levels are variables associated with failure of end of treatment response (ETR) and SVR.

Molecular characterization and clinical epidemiology of HCV in District Dir (Lower), Pakistan

With about 200 million infections globally, Hepatitis C virus (HCV) infection is a major global health threat. The relative prevalence of hepatitis and HCV genotypes/subtypes varies among different geographic regions. Therefore, the present study was conducted to determine the prevalence of hepatitis C and HCV genotypes/subtypes in District Dir (Lower), Pakistan. Blood samples from HCV positive patients were genotyped through multiplex PCR using specific primers for HCV core region. A structured questionnaire was used to obtain information from the patients and data was statistically analyzed for different epidemiological parameters. The molecular evaluation results suggested the prevalence of genotype 3 in this study. The frequency of hepatitis C was found higher in males (P < 0.01). Present study suggests injections received at local clinics as a highly significant mode of HCV transmission to these patients (P < 0.002). These findings might be helpful for clinicians and related health care personnel to assess status of this important disease and highlight the need for more detailed evaluation of this devastating disease in order to frame better treatment strategies.

Epidemiology of Chronic Hepatitis C Infections at a Tertiary Care Centre in Oman

Objectives

Chronic hepatitis C (CHC) is a leading cause of liver cirrhosis and hepatocellular carcinoma (HCC) worldwide. However, there is a lack of data regarding the epidemiology of CHC in Oman. This study aimed to describe the clinicopathological characteristics and outcomes of CHC-infected patients at a tertiary care hospital in Oman.

Methods

This retrospective descriptive hospital-based study included all CHC-infected patients who presented to the Sultan Qaboos University Hospital (SQUH) in Muscat, Oman, between January 2010 and December 2015. The baseline demographic, clinical, laboratory and radiological data of the patients were analysed.

Results

A total of 603 CHC-infected patients were identified during the study period; of these, 65.8% were male and the mean age was 44.8 ± 16.5 years. The main risk factors associated with CHC infection were intravenous drug abuse (23.9%) and a history of blood transfusions (20.7%). The most prevalent virus genotypes were 1 and 3 (44.0% and 35.1%, respectively). Upon initial presentation, 33.0% of the cohort had liver cirrhosis; of these, 48.7% had decompensated cirrhosis and 23.1% had HCCs. Liver transplantation was only performed for 7.5% of the cirrhosis patients, mostly as a curative treatment for HCC.

Conclusion

The implementation of national policies to prevent hepatitis C transmission and encourage the early screening of at-risk patients is recommended to reduce the burden and consequences of this disease in Oman.

Distribution of Hepatitis C Virus Genotypes in Patients with Major β-Thalassemia in Mashhad, Northeast Iran

BACKGROUND

Hepatitis C virus (HCV) is considered to be the major cause of post-transfusion hepatitis in patients with thalassemia. We aimed to determine the HCV prevalence, genotypes, and viral load among patients with major β-thalassemia in Mashhad, Iran.

METHODS

Medical records of all 550 patients with major β-thalassemia who referred to ThalassemiaHemophilia Center of Mashhad (Sarvar Clinic) were reviewed from October to November 2011. Plasma samples of the patients were tested for the presence of anti-HCV antibodies by enzyme linked immunosorbent assay. Real-time polymerase chain reaction (PCR) was used to determine viral genotype and HCV RNA titer.

RESULTS

HCV antibodies were detected in 37 individuals (6.73%) including 17 men and 20 women with mean age of 25.2 ± 8.4 years. The PCR analysis was performed for 27 patients, of whom HCV RNA was detected in 17 patients (63.0%). Viral titers were investigated in 14 subjects and a high viral load more than 600000 copies/mL was observed in 6 patients (42.9%). The most prevalent genotypes were 3a (50.0%) followed by 1a (37.5%). No significant correlation was found between genotype and age, sex, serum ferritin, liver tests, and HCV RNA titer.

CONCLUSION

HCV infection among patients with thalassemia is more common than general population in Mashhad, northeast Iran. The dominant HCV subtype is 3a followed by 1a. These findings could help health authorities to provide preventive measures, and practitioners to choose the right protocol of treatment for the patients.

Viral Phylogenomics Using an Alignment-Free Method: A Three-Step Approach to Determine Optimal Length of k-mer

The development of rapid, economical genome sequencing has shed new light on the classification of viruses. As of October 2016, the National Center for Biotechnology Information (NCBI) database contained >2 million viral genome sequences and a reference set of ~4000 viral genome sequences that cover a wide range of known viral families. Whole-genome sequences can be used to improve viral classification and provide insight into the viral “tree of life”. However, due to the lack of evolutionary conservation amongst diverse viruses, it is not feasible to build a viral tree of life using traditional phylogenetic methods based on conserved proteins. In this study, we used an alignment-free method that uses k-mers as genomic features for a large-scale comparison of complete viral genomes available in RefSeq. To determine the optimal feature length, k (an essential step in constructing a meaningful dendrogram), we designed a comprehensive strategy that combines three approaches: (1) cumulative relative entropy, (2) average number of common features among genomes, and (3) the Shannon diversity index. This strategy was used to determine k for all 3,905 complete viral genomes in RefSeq. The resulting dendrogram shows consistency with the viral taxonomy of the ICTV and the Baltimore classification of viruses.

The treatment of HCV in patients with haemoglobinopathy in Kurdistan Region, Iraq: a single centre experience

Various variables that might influence the rapid and sustained virological response to recombinant PEG-IFN-α-2a were explored in Iraqi HCV-infected patients with haemoglobinopathy. Forty-three patients were evaluated for the relationship between rapid virological response (RVR), IL-28B polymorphism, viral load, liver enzyme levels, blood group, ultrasound findings, or HCV genotype and the sustained virological response (SVR) achievement. The overall RVR was 55·81% while the overall SVR was 53·49%. SVR in patients that achieved RVR was 82·61% (P = 0·0004). A significant association was found between initial alanine transaminase levels and viral load with SVR achievement (P = 0·025) and (P = 0·004), respectively. Thirty-two (74%) out of 43 of our samples were host genotyped at the IL-28B locus as CC, a significant association was found between CC group and SVR achievement (P = 0·04). Of our samples, 23/43 (53%) were typed as HCV genotype 4, 10/43 (23%) as genotype 1, 9/43 (20·9%) as genotype 3 and 1/43 (2·3%) as genotype 2. A significant association was found between genotype 3 and SVR achievement (P = 0·006). Multivariate analysis showed that only RVR achievement independently associated with SVR in the Iraqi population (P = 0·00). These results can be used to classify the patients requiring the more expensive new direct-acting antiviral drugs.

Distribution of Hepatitis C Virus Genotypes in Bahrain

BACKGROUND

Approximately 170 million people are infected with Hepatitis C virus (HCV) worldwide, making it one of the world's major infectious diseases. There are no published population based studies about the prevalence of HCV genotypes in Bahrain.

OBJECTIVES

Therefore, the aim of the present study was to investigate the prevalence and distribution of HCV genotypes and subtypes among a large sample of patients with chronic HCV infection in Bahrain.

PATIENTS AND METHODS

Serum samples were collected from 202 HCV positive patients; of them 128 had a viral load (> 500 IU/mL) suitable for the type-specific genotyping assay. Gender-wise and age-wise differences in the distribution of HCV genotypes were determined by Chi Square and Fisher's Exact tests.

RESULTS

The predominant genotype among Bahraini patients was type 1 (36.71%), followed by genotypes 3 and 4 (15.6% each) and the lowest frequency was found for genotype 2 (3.9%). Among genotype 1, subtype 1b had the highest frequency (21.09%), followed by subtype 1a (14.06%). Among genotype 3, subtype 3a had the highest frequency (11.72%), while among genotype 4, most of subtypes were undetermined. The frequency of all different HCV genotypes was higher in male patients compared to female patients. Genotype 1 was most common in the age group of 51 - 60 years (38.3%), genotype 2 in 21 - 30 years (60%) and genotype 3 in 51 - 60 years (30%), while genotype 4 was most frequent among the age group > 61 (40%).

CONCLUSIONS

The most common HCV genotype in Bahrain was subtype 1b followed by 1a and 3a. Further studies involving sources of transmission in Bahrain are required to enhance control measures for HCV infection.

Geographic distribution of hepatitis C virus genotypes in pakistan

BACKGROUND

Distribution of Hepatitis C Virus (HCV) genotypes may be changed over time. Epidemiological Studies on distribution patterns of HCV genotypes in Pakistani population might assist for better treatment options and preventive strategies.

OBJECTIVES

This study was conducted to determine distribution patterns of HCV genotypes in different geographical regions of Pakistan.

PATIENTS AND METHODS

In this cross-sectional study, 1818 randomly selected patients from different geographical regions of Pakistan, diagnosed with HCV infection by the third generation Enzyme Linked Immunosorbent Assay (ELISA), were included between April 2011 and December 2013. HCV RNA was detected in serum samples of patients by Reverse Transcription Polymerase Chain Reaction (RT- PCR) of the core region. Qualitative PCR was performed to determine viral load. HCV genotyping was performed by RT-nested PCR using type-specific primers of the core region. Frequency of different genotypes among patients was assessed according to gender, age and geographical region at the time of sampling.

RESULTS

Of 1818 HCV RNA positive samples, HCV genotypes PCR fragments were detected in 1552 (85.5%) samples. HCV genotype 3a was the predominant genotype (39.4%) followed by genotype 2a (24.93%). HCV genotype 3 was the predominant genotype in Punjab and Sindh regions, while genotype 2 was the most predominant genotype in Khyber Pakhtunkhwa region and the second predominant genotype after genotype 3 in Sindh region. The incidence of genotype 2a is increasing in our country with decrease in the incidence of genotype 3a. A higher incidence of HCV various genotypes were observed among male patients and those younger than 45 years.

CONCLUSIONS

This study may facilitate treatment options and preventive strategies in Pakistan.

Prevalence of hepatitis C virus genotypes in district bannu, khyber pakhtunkhwa, pakistan

Determination of an individual's hepatitis C virus (HCV) genotypes prior to antiviral therapy has become increasingly important for the clinical management and prognosis of HCV infection. Therefore, this study was conducted to investigate the prevalence of HCV genotypes in HCV infected patients of district Bannu in Khyber Pakhtunkhwa region of Pakistan. Serum samples of 117 seropositive patients were screened for HCV-RNA by using reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) and then PCR positive samples were subjected to HCV genotyping. Out of 117 seropositive samples, 110 samples were found positive by PCR analysis. Genotype 3a was the most prevalent one detected in 38% of patients, followed by genotype 3b in 21% of patients, and then genotype 2a in 12% of patients. However 21% of HCV-PCR positive samples could not be genotyped by method used in this study. Genotype 3a was the most prevalent genotype in patients of all age groups and its prevalence was found high among patients with increasing age (>34 years). Moreover, genotypes 3a and 3b were found to be the most prevalent genotypes in patients with history of shaving by barbers, receiving multiple injections, and dental procedures. In conclusion there is need of further investigation of genotypes of HCV by using more sensitive assays and considering large sample size in district Bannu.

Distribution of hepatitis C virus genotypes in Iranian chronic infected patients

BACKGROUND

Hepatitis C virus (HCV) has different genotypes throughout the world. Since the determination of which antiviral treatment to be applied is related to HCV genotypes, identification of an individual's HCV genotypes prior to antiviral therapy is critical.

OBJECTIVES

The purpose of this study was to investigate the distribution of HCV genotypes in a large population of Iranian HCV infected patients.

PATIENTS AND METHODS

Eleven thousand, five hundred and sixty one patients with chronic HCV infection which referred to hospitals related to the Tehran University of Medical Sciences and Tehran Hepatitis Center-Clinical Department of Baqiyatallah Research Center for Gastroeneterology and Liver Disease from March 2003 to December 2011 were enrolled. Following extraction of viral RNA of the serum, HCV-RNA was detected using reverse transcriptase-nested polymerase chain reaction (RT-nested PCR) and then HCV genotypes analyzed by restriction fragment length polymorphism (RFLP) assay.

RESULTS

The mean age of patients was 37.6 ± 14.2 years (range: 1-87). The highest frequency was noted for subtype 1a (44.9%) followed by subtype 3a (39.6%), and 1b (11.3%). Mixed HCV genotypes were also found in 2.5% of the total cases. Subtype 1a was the most frequent genotype in patients over 40 years of age (46.1% versus 42.4%) and subtype 3a was the most frequent in patients under 40 years old (41.5% versus 38.9%).

CONCLUSIONS

This study suggested that the dominant HCV subtype among Iranian patients was 1a followed by subtype 3a.

Prevalence of risk factors for hepatitis C virus in HIV-infected and HIV/hepatitis C virus-coinfected patients

METHODS

A sample of patients with HIV completed a questionnaire identifying their demographic characteristics and risk factors for hepatitis C virus (HCV). A chart review was conducted to confirm the information obtained using the questionnaire. Risk factors associated with coinfection status at alpha level of 0.1 in univariate analysis were entered into a multivariate Cox regression model.

RESULTS

Of the 242 HIV-positive patients analyzed, 168 were HIV-infected and 74 were HIV/HCV-coinfected. Risk factors that were significantly different between HIV-monoinfected and HIV/HCV-coinfected subjects included intravenous drug use, snorting drugs, sharing razors or toothbrushes, being in prison, the presence of one or more tattoos, sex for money or drugs, sex with an intravenous drug user and man who has sex with men. In a multivariate regression model, only intravenous drug use remained as a significant risk factor/predictor of HCV/HIV coinfection. A subanalysis identified risk factors more prevalent among coinfected men who have sex with men, including intravenous drug use, sharing razors/toothbrushes, tattoos, sex for money or drugs, sex with an intravenous drug user, and a history of having 11 or more sexual partners. A history of having had a sexually transmitted disease and 11 or more sex partners was more prevalent among HIV-monoinfected men who have sex with men.

CONCLUSIONS

HIV/HCV coinfection was associated with intravenous drug use but not with sexual risk factors.

Distribution of hepatitis C virus genotypes among hemodialysis patients in Tehran--a multicenter study

Hepatitis C virus has substantial heterogeneity of genotypes throughout the world. The aim of this study was to determine the frequency of HCV genotypes, risk factors and clinical implications in cases of hemodialysis living in Tehran. A total of 155 patients treated by hemodialysis, who had been identified to be anti-HCV positive at 45 medical centers in Tehran, were enrolled. Genotyping was using restriction fragment length polymorphism (RFLP) on HCV-RNA positive samples. HCV-RNA was detected in 66 (42.6%) patients. Genotyping of HCV-RNA positive serum samples demonstrated that subtypes 3a and 1a were predominant accounting for 30.3 and 28.8%, respectively. The distribution of other HCV genotypes showed genotype 1b, 18.2%; genotype 4, 16.7%; mixed genotypes 1a and 1b, 3%; and genotype 3b, 3%. Genotype 2 was not detected in this study. Statistically significant differences were identified between HCV infected and non-HCV infected patients regarding history of hemodialysis unit changes more than two times (P = 0.01), and history of hemodialysis for more than 20 years (P = 0.02). However, blood transfusion, mean duration of hemodialysis therapy and the history of solid organ transplantation did not differ between these two groups. This study indicates that the dominant HCV genotypes among patients treated by hemodialysis living in Tehran were 3a and 1a, and considering previous reports from the general population, genotype 4 was strongly associated with hemodialysis. The duration of treatment by hemodialysis and, in turn, more hemodialysis unit changes will lead to more frequent HCV infections.

Molecular epidemiology of hepatitis C virus in Iran as reflected by phylogenetic analysis of the NS5B region

Hepatitis C virus (HCV) subtypes were determined in 125 Iranian patients by phylogenetic analysis within the NS5B or 5'-UTR/core regions. Subtypes 1a and 3a were predominant accounting for 47 and 36%, whereas 1b and 4 accounted for 8 and 7%. This subtype distribution differs from that of Turkey and Pakistan, where subtypes 1b and 3a dominate and also from neighbouring Arabic countries where subtype 4 is the prevalent genotype. The Iranian 1a and 3a strains formed subclusters in the dendrogram indicating that these subtypes are indigenous to Iran. In contrast, the 1b strains intermixed with strains derived worldwide. Subtype 1a was frequent in South Iran (70%), while 3a was more prevalent in North-West Iran (83%), a region with a high proportion of Turkish inhabitants. Patients infected by blood products had more frequently subtype 1a (57%), while younger drug users had more frequently subtype 3a (54%). Genotype 4 was over-represented among haemodialysis patients in Tehran. One strain, most similar to genotype 5, was highly divergent in the NS5B region and further analysis is needed to assess the systematic status of this strain. In half of the patients with unknown source of infection only the 5'-UTR could be amplified, most of which were from North-West Iran and from patients younger than those with unknown source of infection with typable strains, mean age 29 versus 43 years. In conclusion, the NS5B sequence data revealed population based subtype patterns in Iran, the further study of which may help to understand the molecular epidemiology of HCV in a low-endemic area.

Phylogenetic analysis of hepatitis C virus isolates indicates a unique pattern of endemic infection in Cameroon

Hepatitis C virus (HCV) is a blood-borne pathogen that poses a significant threat to public health worldwide. The genetic diversity and distribution of HCV genotypes in non-Western countries, particularly subSaharan Africa, is poorly documented. This study reports a phylogenetic analysis of core and NS5B gene sequences of 37 HCV strains sampled in Cameroon. A high level of genetic diversity of both genotypes 1 and 4 was found, indicating a unique pattern of long-term HCV infection that has not been observed elsewhere. These results lead to the hypothesis that these HCV genotypes originated and diversified in west Central Africa before spreading to other regions.

Viral evolution and epidemiology

This review highlights recent research on viral evolution and its use towards understanding disease pathogenesis and epidemiology. The development of techniques such as enzymatic amplification of viral genomes and automated sequencing has led to a dramatic increase in the amount of sequence information from clinical samples. These sequences (RNA or DNA, or the amino acids they encode) have been compared by complex computer algorithms to generate evolutionary trees or phylogenies of natural virus variants, which can sometimes be used to correlate viral genotype with phenotype. Understanding the rates and types of evolution that occur during the transmission of viruses has considerable impact on the design of methods for the control of virus diseases.

Molecular epidemiology of animal virus diseases

In this review the application of methods of molecular epidemiology, particularly the combined approach of amplifying defined fragments of viral genomes using the polymerase chain reaction and subsequent nucleotide sequencing analysis, is described. Emphasis is put on examples of a few important diseases (e.g. those caused by morbilliviruses, rhabdoviruses, pestiviruses and aphthoviruses) to demonstrate the impact of this methodology. Molecular epidemiology is already an important and very sensitive tool to study the evolution of viruses at a level superior to previous methodologies and providing a better understanding of epidemiological relationships.