Expanded Diversity and Host Range of Bovine Hepacivirus-Genomic and Serological Evidence in Domestic and Wild Ruminant Species.

The hepatitis C virus (HCV)-related bovine hepacivirus (BovHepV) can cause acute as well as persistent infections in cattle. The true clinical relevance of the virus is not yet known. As reliable antibody detection methods are lacking and prevalence studies have only been conducted in cattle and few countries to date, the true distribution, genetic diversity, and host range is probably greatly underestimated. In this study, we applied several RT-PCR methods and a nano-luciferase-based immunoprecipitation system (LIPS) assay to analyze bovine serum samples from Bulgaria as well as wild ruminant sera from Germany and the Czech Republic. Using these methods, BovHepV infections were confirmed in Bulgarian cattle, with viral genomes detected in 6.9% and serological reactions against the BovHepV NS3 helicase domain in 10% of bovine serum samples. Genetic analysis demonstrated co-circulation of highly diverse BovHepV strains in Bulgarian cattle, and three novel BovHepV subtypes within the genotype 1 could be defined. Furthermore, application of a nested RT-PCR led to the first description of a BovHepV variant (genotype 2) in a wild ruminant species. The results of this study significantly enhance our knowledge of BovHepV distribution, genetic diversity, and host range.

Serological evidence of hepatitis E virus infection in pigs from Northern Bulgaria.

The purpose of the present study was to investigate pigs in Northern Bulgaria for serological evidence of hepatitis E virus (HEV). Sera from 225 individuals from three industrial farms were tested for anti­HEV IgG antibodies. The overall HEV seroprevalence was 36% (81/225); weaners 6.8% (5/74); fattening pigs 38.7% (29/75) and in sows 61.8% (47/76). Compared to weaners, HEV positivity was higher in fattening pigs and sows: OR = 8.70 (95% CI: 3.14­24.12) and OR = 22.37 (95% CI: 8.07­61.96), respectively. These data confirm that HEV is endemic in pigs throughout Bulgaria, and can be a Public Health problem due to the transmission of HЕV to humans through the consumption of pork meat and pork products.

Seroprevalence of Hepatitis E Virus Infection Among Wild Boars in Western Bulgaria.

Scientific evidence indicates that hepatitis E virus (HEV) infection is a zoonotic disease. Domestic pigs and wild boars are the main animal reservoir for HEV worldwide. The aim of this study was to analyze the seroprevalence of HEV infection among wild boars in western Bulgaria. Serum samples from 240 wild boars from two regions of the country (northwestern and southwestern) were tested for anti-HEV Immunoglobulin G (IgG) antibodies. The overall HEV seroprevalence was 40.8% (98/240); northwestern region 40.0% (48/120); southwestern region 41.7% (50/120). HEV seropositivity in the southwestern region was higher than in the northwestern region: odds ratio = 1.071 (95% confidence interval: 0.640-1.793). This research provided the first seroprevalence study to HEV in wild boars from western Bulgaria.

High Seroprevalence of Hepatitis E Virus Infection Among East Balkan Swine (Sus scrofa) in Bulgaria: Preliminary Results.

The East Balkan swine (Sus scrofa) is the only aboriginal pig breed in Bulgaria, and it is indigenous to the eastern part of the country. The aim of the present study was to investigate East Balkan swine (EBS) in Bulgaria for serological evidence of hepatitis E virus (HEV). Sera from 171 swine from two parts of the country (northeastern and southeastern) were tested for anti-HEV IgG antibodies. The overall HEV seroprevalence was 82.5% (141/171), and for weaners it was 77.2% (44/57), for fattening pigs 79.0% (45/57), and for adults 91.2% (52/57). HEV positivity was higher in fattening pigs and adults compared to weaners: OR = 1.108 (95% CI: 0.456-2.692) and OR = 3.073 (95% CI: 1.016-9.294), respectively. This study provides the first evidence of exposure to HEV in EBS from Bulgaria.

Seroprevalence of Hepatitis E Virus Infection in Pigs from Southern Bulgaria.

Hepatitis E virus (HEV) has been isolated from humans and several animals' species. During the last years, the knowledge of HEV infection dramatically changed and enriched. The aim of this study was to estimate the seroprevalence of HEV in industrial pigs in different districts of Southern Bulgaria. Three hundred sixty swine serum samples were tested for anti-HEV IgG antibodies. The samples were collected from four industrial farms from three districts of Southern Bulgaria. HEV-specific antibodies in porcine serum were detected by enzyme-linked immunosorbent assay (PrioCHECK HEV Ab porcine). The overall HEV seroprevalence was 60.3%. The seropositivity varied widely depending on age groups and investigated farms. The overall prevalence in weaners was 25%, in fattening pigs 75.8%, and in group of sows was found the highest HEV positivity of 80%. The occurrence of HEV positivity in sows and fattening pigs presented odds ratio (OR) = 17.200 (95% confidence interval [CI]: 8.8-33.7) and OR = 11.342 (95% CI: 6.1-21.0), respectively, compared to weaners. The study indicated that HEV is widespread in industrial farms in Bulgaria and presented high seroprevalence in pigs. The results found that HEV seropositivity showed age dependency. The National Health Authorities should raise awareness of HEV and its zoonotic potential.

Serological Evidence of Borrelia burgdorferi, Anaplasma phagocytophilum and Ehrlichia Spp. Infections in Horses from Southeastern Bulgaria.

Lyme Borreliosis and granulocytic anaplasmosis are less extensively studied in horses than in dogs and humans. Equine ehrlichiosis is not known in Europe and is in the initial stage of investigation in South, Central, and North America. The aim of this study was to determine the seroprevalence of these infections in Bulgaria. A total of 155 horses were investigated from five regions in Southeastern Bulgaria. Horses were tested for Borrelia burgdorferi, Anaplasma phagocytophilum, and Ehrlichia spp. antibodies by a commercial rapid ELISA test. B. burgdorferi and A. phagocytophilum antibodies were found in all five regions (Burgas, Sliven, Stara Zagora, Haskovo, and Kardzhali) at frequencies of 36/155 (23.2%; 95% CI: 16.8-30.7%; ranging by region from 6.4% to 50%) and 31/155 (20%; 95% CI: 14-27.2%; ranging by region from 10% to 30.8%), respectively. Antibodies against Ehrlichia spp. were found in horses from three regions (Burgas, Stara Zagora, and Haskovo) at a rate of 6/155 (3.9%; 95% CI: 1.4-8.2%; ranging by region from 5.7% to 6.4%). The combination of B. burgdorferi/A. phagocytophilum (11/155; 7.1%; 95% CI: 3.6-12.3%) was the most common coexposure observed, followed by B. burgdorferi/Ehrlichia spp. (2/155; 1.3%; 95% CI: 0.2-4.6%) and A. phagocytophilum/Ehrlichia spp. (1/155; 0.6%; 95% CI: 0-3.5%). The study shows that horses in Bulgaria are exposed or coexposed to three tick-transmitted zoonotic bacterial species. Furthermore, it reports Ehrlichia spp. seroreactivity in equines in Europe.