Phylogenetic Analysis of NS5B Region of Hepatitis C Genotype 3a Virus among Different Risk Groups in Iran

Background: Hepatitis C virus (HCV) is a major cause of liver diseases. Transmission of HCV, as a blood-borne virus, is a major concern for the safety of blood products. In Iran, intravenous drug abuse is a major risk factor for HCV transmission. Recently a change in the distribution of HCV genotype among Iranian blood donors has been reported, and genotype 3a is reported as the most frequent genotype. Also, genotype 3a is the dominant genotype among IDUs. Objective: To investigate the association between HCV genotype 3a circulating in the community, sequences of HCV genotype 3a were analyzed among different risk groups in Iran. Methods: In this cross-sectional study, a partial sequence of the NS5B region of the HCV genome was isolated from 58 blood donors, 48 intravenous drug users (IDUs), and 31 patients with inherited bleeding disorders (IBDs) infected with HCV genotype 3a were included. The published sequence data were obtained from the Gen Bank database and were compared to construct the phylogenetic trees. Results: Of 58 blood donors infected with subtype 3a, 31 (53.5%) reported the risk of intravenous drug abuse. In the phylogenetic tree, no separate cluster was formed to differentiate between HCV sequences in blood donors and IDUs. A cluster at the middle level was found in the phylogenetic tree formed by sequences from blood donors, IDUs, and patients with inherited bleeding disorders. Conclusions: The phylogenetic tree showed the phylogenetic mixing of genotype 3a sequences in BDs, IBD patients, and IDUs. The results confirmed the extensive transmission of IDU-related genotype 3a towards the general population.

Detection of Atypical porcine pestivirus in Swedish pigs with congenital tremor type A-II

Background Congenital tremor type A-II is a neurological disorder characterized by tremor of the head and body of new-born piglets. The suggestive causative agent of the disease is the recently found atypical porcine pestivirus. The virus has been detected in piglets suffering from congenital tremor in central Europe, South and North America and in China but no studies has so far not been performed in the Nordic countries, hence, the aim of this study was to investigate the prevalence of atypical porcine pestivirus in Swedish piglets. From June 2017 – June 2018, 15 piglets from four Swedish farms with ongoing outbreaks of congenital tremor, and 13 piglets with splay leg, from four different farms, were investigated for presence of APPV RNA in brain tissue. Matched healthy control piglets (n=8) were also studied. Two APPV-specific RT-qPCR:s targeting the NS3 and NS5B region, respectively, were used. A retrospective study was performed in the same manner on material from Swedish piglets with congenital tremor sampled in 2004 (n=11) and 2011/2012 (n=6). Results Atypical porcine pestivirus-RNA was detected in 93% (27/29) of the piglets suffering from congenital tremor. All samples from piglets with congenital tremor from 2004 (n = 11) and 2012 (n = 3) were PCR-positive with respect to APPV. All of the healthy controls (n=8) were negative for APPV. The piglets with congenital tremor sampled 2017-2018 had an odds ratio of 271 (95% CI 12.1 to 6096.8, z = 3.5, P = 0.0004) to test positive for APPV by qRT-PCR compared to the healthy piglets (Fishers exact test p < 0.0001). These findings make it interesting to continue investigating APPV in pigs in Sweden, as most of the virus details is unknown to date. Conclusion This is the first description of atypical porcine pestivirus in piglets with congenital tremor type A-II in Sweden and the Nordic countries. The virus has been present in the Swedish pig population since at least 2004.