Tracing the epidemic history of hepatitis C virus genotypes in Saudi Arabia

A review on hepatitis C virus: role of viral and host-cellular factors in replication and existing therapeutic strategies

Background

Hepatitis C virus, a member of Flaviviridae is a single-stranded positive-sense RNA virus infecting 62–79 million people around the globe. This blood-borne virus is one of the leading causes of liver diseases worldwide. This review aims to identify novel potential genes linked to cellular host factors, as well as revise the roles of each gene in hepatitis C Virus infection. This review also aims to provide a comprehensive insight into therapeutic advancements against HCV.

Methods

For this review article, 190 articles were searched via PubMed Central, Bio-One, National Academy of Science, Google Scholar, and Worldwide Science. 0ut of these 190 studies, 55 articles were selected for this review. The inclusion of articles was done on the criteria of high citation and Q1 ranking.

Results

The information gathered from previously published articles highlighted a critical link between host-cellular factors that are important for HCV infection.

Conclusion

Although many advancements in HCV treatment have been made like DAAs and HTAs, the development of a completely effective HCV therapy is still a challenge. Further research on combinations of DAAs and HTAs can help in developing a better therapeutic alternative. Keywords: Hepatitis C virus, Replication cycle, Non-structural proteins, Host-cellular factors, Treatment strategies

Overview of the epidemic history of Hepatitis C uncommon subtypes 2i and 4d in Tunisia and in the world

The impressive improvements in qua therapy efficacy alone are not sufficient to substantially reduce the Hepatitis C Virus burden because of the usually very long asymptomatic phase of the infection. In turn, this renders prevention of infection of great importance. The value of learning how the virus has spread in the past is that this can provide clues as to what routes the virus likely spreads through today, which can feedback into prevention policy. In Tunisia, HCV subtypes 2i and 4d are minor circulating subtypes. Here, we applied a Bayesian Markov Chain Monte Carlo method for visualization of spatial and temporal spread of HCV-2i and 4d in Tunisia and some other countries in the world. Our analysis included sequences retrieved from Genbank and isolated from several countries in the world; 21 HCV-NS5B subtype 2i genome sequences obtained during the period 2002-2020 and 206 HCV-NS5B-4d sequences detected between 2000 and 2019. Phylogenetic analysis revealed that two geographical clusters could be identified in HCV-2i tree with two clearly distinguished clusters in HCV-4d Tree. The estimated time for the most recent common ancestor suggested that current HCV-2i strains emerged in 1963 [1930, 1995] and current HCV-4d strains emerged in 1992 [1988, 1996] in Tunisia and other countries from the world investigated in the present study.

Hepatitis C virus genotypes in Saudi Arabia: a future prediction and laboratory profile

BACKGROUND

Hepatitis C virus (HCV) genotypes and subtypes are considered an important tool for epidemiological and clinical studies and valuable markers for disease progression and response to antiviral therapy. The aim of this study was to identify the prevalence of HCV genotypes and their relation to socio-demographic factors particularly age and sex, various biochemical profiles and viral load.

METHODS

The records (630) of Saudi patients positive for HCV (2007-2011) reported in the system of the Molecular Pathology Laboratory at a tertiary reference hospital in Riyadh, Saudi Arabia were analyzed. Socio-demographic characteristics, liver biochemical profile, viral load and co-infection with HBV and HIV were retrieved from the hospital database. The associations of continuous and categorical variables with genotypes were analyzed.

RESULT

The overall mean age of the surveyed patients was 59 years ±0.5 years (21% were <50 years (p = 0.02). The rate of infection is lower in males than in females (47.6% vs. 52.4%). HCV genotype 4 was the most prevalent (60.7%), followed by genotype 1 (24.8%). However, genotype 1 and 3 were found more in males (29.7% vs. 20.3% and 6% vs. 2.1%, respectively, p = 0.001), while genotype 2 and 4 were more among females (4.8% vs. 2% and 68.5% vs. 52.3%, respectively). In addition, genotype 1 was found dominant in younger males (33.8%). Biochemical parameters across gender showed significant variation in particular for the ALT (p = 0.007). The mean viral load was significantly higher in genotype 1 than genotype 4 (4,757,532 vs. 1,435,012, p = <001). There is a very low overall percentage of co-infection of HBV or HIV in this study (around 2% for each).

CONCLUSION

Although HCV genotype 4 shows an overall high prevalence in this study, a clear decline in the rate of this genotype was also demonstrated in particular among the younger age group who displayed increasing trends toward the global trend of genotype 1, rather than genotype 4. This finding would be of clinical interest in relation to future planning of the therapy for HCV infected patient.

Molecular characterization and epidemic history of hepatitis C virus using core sequences of isolates from Central Province, Saudi Arabia

The source of HCV transmission in Saudi Arabia is unknown. This study aimed to determine HCV genotypes in a representative sample of chronically infected patients in Saudi Arabia. All HCV isolates were genotyped and subtyped by sequencing of the HCV core region and 54 new HCV isolates were identified. Three sets of primers targeting the core region were used for both amplification and sequencing of all isolates resulting in a 326 bp fragment. Most HCV isolates were genotype 4 (85%), whereas only a few isolates were recognized as genotype 1 (15%). With the assistance of Genbank database and BLAST, subtyping results showed that most of genotype 4 isolates were 4d whereas most of genotype 1 isolates were 1b. Nucleotide conservation and variation rates of HCV core sequences showed that 4a and 1b have the highest levels of variation. Phylogenetic analysis of sequences by Maximum Likelihood and Bayesian Coalescent methods was used to explore the source of HCV transmission by investigating the relationship between Saudi Arabia and other countries in the Middle East and Africa. Coalescent analysis showed that transmissions of HCV from Egypt to Saudi Arabia are estimated to have occurred in three major clusters: 4d was introduced into the country before 1900, the major 4a clade’s MRCA was introduced between 1900 and 1920, and the remaining lineages were introduced between 1940 and 1960 from Egypt and Middle Africa. Results showed that no lineages seem to have crossed from Egypt to Saudi Arabia in the last 15 years. Finally, sequencing and characterization of new HCV isolates from Saudi Arabia will enrich the HCV database and help further studies related to treatment and management of the virus.