Abstract: The genus (HCV) has long been a dynamic group, increasing its number by myriads of species collectively referred to as non-primate hepaciviruses (NPHVs). NPHV exhibits a broad hepatotropism and is often attributed to chronic infection in horses and dogs. However, recent studies and meta-analyses on NPHV in horses have remained inconclusive regarding the determination of risk factors for infection. Therefore, our main goal was to investigate the frequencies and molecular characteristics of NPHV infection linked to geographical location, horse breeds, genders, and ages. For this purpose, we tested the positivity of 152 samples collected from ten cities in Turkey by conventional PCR, targeting the highly conserved 5' UTR sequence, and compiled our results with pedigree data of horses for statistical analyses. We further implemented sequencing of the 5' UTR, NS3, and NS5B regions and used in silico approaches to evaluate the characteristics of our novel isolates. Our results revealed a high incidence of NPHV infection (52.3%), which fluctuated among cities (26.1-75.0%), and comparative statistical analyses indicated that age and geographical region, together with managemental alterations, could be key determinants in NPHV infection. Furthermore, our phylogenetic analyses and 3D modelling approaches on genomic sequences revealed fundamental characteristics of novel NPHV strains. In conclusion, our study contributed to providing a better understanding of NPHV distribution and revealed some hints on diagnostics and good practices for disease prevention.
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Research Overview
This study investigates the prevalence, risk factors, and molecular characteristics of non-primate hepacivirus (NPHV) infection in Turkish horses.
The research highlights how variables like geographic location, age, and horse management affect NPHV infection rates and provides insights into viral genetics for diagnostics and prevention.
Background
Non-primate hepaciviruses (NPHVs) are a diverse group of viruses related to Hepatitis C virus (HCV) but infect non-primate hosts such as horses and dogs.
NPHV has broad liver tissue tropism and can cause chronic infections in these animals.
Previous studies on NPHV infection in horses showed inconclusive results regarding which factors increase infection risk.
Objectives
To determine the prevalence of NPHV infection in horses across different regions in Turkey.
To identify associations between infection rates and factors such as geographic location, horse breed, gender, and age.
To perform molecular characterization of NPHV strains found in Turkish horses to understand viral diversity and implications for diagnostics.
Methodology
Samples were collected from 152 horses from ten cities located in various parts of Turkey.
Conventional PCR targeting the conserved 5′ untranslated region (5′ UTR) of the NPHV genome was used to detect viral presence.
Pedigree and demographic data of the horses were compiled for statistical analysis of infection risk factors.
Sequencing of three genomic regions (5′ UTR, NS3, and NS5B) was performed on positive samples to characterize viral genetic diversity.
Phylogenetic analyses and three-dimensional modeling of viral protein structures were conducted to understand evolutionary relationships and viral features.
Key Findings
The overall NPHV infection frequency was high at 52.3% among the sampled horses.
Infection rates greatly varied among cities, ranging from 26.1% to 75.0%, suggesting a strong geographic influence.
Statistical analyses revealed that horse age and region were significant determinants of infection risk.
Management factors, potentially including horse husbandry and local practices, also appeared to influence infection rates.
Phylogenetic studies showed the newly identified Turkish NPHV strains clustered with known variants but possessed unique genetic features.
3D molecular modeling highlighted structural details of viral proteins important for viral replication and potentially for diagnostic targeting.
Conclusions and Implications
This study provides important epidemiological data that clarifies how NPHV spreads in the horse population in Turkey.
Age and geographical region, coupled with specific management practices, are key factors influencing NPHV infection risk.
Molecular characterization of the virus enhances understanding of viral diversity, which is crucial for improving diagnostic tools.
Findings may inform better horse management and biosecurity measures to reduce the spread of NPHV infections.
The research lays groundwork for future studies aimed at disease control and vaccine development.
Cite This Article
APA
Atasoy MO, Turan T, Özbek R, Işıdan H, Naggar RFE, Afify AF, Rohaim MA.
(2025).
Evaluation of Risk Determinants and Molecular Characterisation for Non-Primate Hepacivirus Infection in Turkish Horses.
Pathogens, 14(12), 1256.
https://doi.org/10.3390/pathogens14121256
Department of Veterinary Virology, Faculty of Veterinary Medicine, Cumhuriyet University, 58140 Sivas, Türkiye.
Turan, Turhan
Department of Veterinary Virology, Faculty of Veterinary Medicine, Cumhuriyet University, 58140 Sivas, Türkiye.
Özbek, Remziye
Department of Veterinary Virology, Faculty of Veterinary Medicine, Cumhuriyet University, 58140 Sivas, Türkiye.
Işıdan, Hakan
Department of Veterinary Virology, Faculty of Veterinary Medicine, Cumhuriyet University, 58140 Sivas, Türkiye.
Naggar, Rania F El
Department of Virology, Faculty of Veterinary Medicine, University of Sadat City, Sadat 32897, Egypt.
Afify, Ahmed F
Virology Research Department, Animal Health Research Institute (AHRI), Agriculture Research Center (ARC), Giza 12618, Egypt.
Rohaim, Mohammed A
Department of Virology, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt.
MeSH Terms
Animals
Turkey / epidemiology
Horses
Hepatitis C / veterinary
Hepatitis C / epidemiology
Hepatitis C / virology
Phylogeny
Hepacivirus / genetics
Hepacivirus / classification
Hepacivirus / isolation & purification
Horse Diseases / virology
Horse Diseases / epidemiology
Risk Factors
Male
Female
5' Untranslated Regions
Conflict of Interest Statement
The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.
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