Border disease virus (BDV) belongs to the genus Pestivirus of the family Flaviviridae. Interspecies transmission of BDV between sheep, cattle, and pigs occurs regularly, sometimes making diagnosis a ...challenge. BDV can yield substantial economic losses, including prenatal and postnatal infections in lambs, which are the primary source of infection and maintenance of the virus in the population. Since BDV is antigenically and genetically related to bovine viral diarrhea virus (BVDV), it might pose a significant risk to cattle, influencing BVDV eradication campaigns. Similarly, the presence of BDV in swine herds due to pestivirus spillover between small ruminants and pigs might cause uncertainty in classical swine fever virus (CSFV) diagnostics. Therefore, knowledge of BDV epidemiology in different geographical regions will help prevent its spread and optimize control measures. Previous epidemiological studies have shown that various BDV genotypes are predominant in different countries. This review provides an overview of the spread of BDV world-wide in different host species.
Small ruminant lentiviruses (SRLVs) are found in sheep in Germany and Iran. SRLVs have been classified into four genotypes: A-C and E. Genotype A has been subdivided into 20 subtypes. Previous ...studies suggested that, first, the ancestors of genotype A are those SRLVs found in Turkey, second, the evolution of SRLVs is related to the domestication process, and, third, SRLV infection was first observed in sheep in Iceland and the source of that infection was a flock imported from Germany. This study generated, for the first time, partial SRLV sequence data from German and Iranian sheep, enhancing our knowledge of the genetic and evolutionary relationships of SRLVs, and their associations with the domestication process. Based on 54 SRLV sequences from German and Iranian sheep, our results reveal: (1) SRLV subtypes A4, A5, A11, A16 and A21 (new) are found in German sheep and A22 (new) in Iranian sheep. (2) Genotype A has potentially an additional ancestor (A22), found in Iran, Lebanon and Jordan. (3) Subtype A22 is likely an old version of SRLVs. (4) The transmission routes of some SRLVs are compatible with domestication pathways. (5) This study found no evidence of Icelandic subtype A1 in German sheep.
African swine fever (ASF) is a severe haemorrhagic infectious disease affecting suids, thus representing a great economic concern. Considering the importance of the early diagnosis, rapid point of ...care testing (POCT) for ASF is highly demanded. In this work, we developed two strategies for the rapid onsite diagnosis of ASF, based on Lateral Flow Immunoassay (LFIA) and Recombinase Polymerase Amplification (RPA) techniques. The LFIA was a sandwich-type immunoassay exploiting a monoclonal antibody directed towards the p30 protein of the virus (Mab). The Mab was anchored onto the LFIA membrane to capture the ASFV and was also labelled with gold nanoparticles for staining the antibody-p30 complex. However, the use of the same antibody for capturing and as detector ligand showed a significant competitive effect for antigen binding, so required an experimental design to minimize reciprocal interference and maximize the response. The RPA assay, employing primers to the capsid protein p72 gene and an exonuclease III probe, was performed at 39 °C. The limit of detection of the method was assessed using a plasmid encoding the target gene and resulted in 5 copy/μL. The new LFIA and RPA were applied for ASFV detection in the animal tissues usually analysed by conventional assays (i.e., real-time PCR), such as kidney, spleen, and lymph nodes. A simple and universal virus extraction protocol was applied for sample preparation, followed by DNA extraction and purification for the RPA. The LFIA only required the addition of 3% H2O2 to limit matrix interference and prevent false positive results. The two rapid methods (25 min and 15 min were needed to complete the analysis for RPA and LFIA, respectively) showed high diagnostic specificity (100%) and sensitivity (93% and 87% for LFIA and RPA, respectively) for samples with high viral load (Ct < 27). False negative results were observed for samples with low viral load (Ct > 28) and/or also containing specific antibodies to ASFV, which decreased antigen availability and were indicative of a chronic, poorly transmissible infection. The simple and rapid sample preparation and the diagnostic performance of the LFIA suggested its large practical applicability for POC diagnosis of ASF.
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•Two biosensors for the rapid and on-site detection of African Swine Fever virus in blood and tissues were developed.•The molecular test, based on recombinase polymerase amplification, and the antigen test, based on lateral flow immunoassay.•An effective universal method was used to resolve false positive results due to interfering substances in target tissues.•This protocol extends the application of LFIA to these matrices in general.
To gain further insight into the genomic features of border disease virus (BDV), we determined the nearly complete genome sequence of isolate TO/121/04 from an aborted ovine fetus. Its genome ...contains a single open reading frame (ORF), which comprises 11,681 nucleotides encoding a polyprotein of 3893 amino acids. Phylogenetic analysis of the near full-length genome sequence showed that the BDV isolate differed significantly from all ovine pestiviruses identified so far, thus re-affirming the presence in Italy of this novel genetic group, termed BDV-7.
Recent studies have explored the seropositivity of
(BoHV-1) in water buffaloes, suggesting the urgency for developing strategies to eradicate the virus involving both cattle and water buffaloes. ...However, in Europe, the glycoprotein E (gE) deleted marker vaccines against BoHV-1 are commercially available only for the cattle industry. This study, for the first time, evaluated the safety and efficacy of a commercial inactivated gE-deleted marker vaccine in water buffalo. Five animals devoid of BoHV-1-neutralizing antibodies were vaccinated via intramuscular route. Five additional animals served as an unvaccinated control group. Sixty days after the first immunization, all animals were experimentally infected with a virulent BoHV-1via intranasal route. A detectable BoHV-1-humoral immune response was observed in the vaccinated group on post-vaccination day 30, whereas the antibodies appeared on post-challenge day 10 in the control group. Moreover, the vaccinated animals neither show viral shedding nor clinical signs compared to the control upon challenge. However, post-challenge, the BoHV-1-specific humoral and cell-mediated immune responses were significantly more increased in vaccinated animals than the control animals. Overall, the present study provides evidence of both the safety and efficacy of an inactivated gE-deleted marker vaccine against BoHV-1 in water buffaloes.
Bovine respiratory syncytial virus (BRSV) is an economically significant pathogen in cattle production worldwide. Usually, it is detected in outbreaks of respiratory disease, most often during the ...winter period. During the middle of October 2018, a serious outbreak of respiratory disease occurred in a cattle farm comprising about 300 heads located in Central Italy. The herd was affected by a severe flu‐like syndrome unresponsive to any antibiotic treatment. Within 3 weeks, 39 adult animals died, and 12 abortions occurred. Direct and indirect laboratory tests were performed to detect the main pathogens causing the respiratory disease of the affected cattle. The results of laboratory investigations provided evidence of an acute and severe BRSV syndrome characterized by unusual mortality. In order to investigate the molecular underpinnings of this syndrome, phylogenetic analysis of the BRSV strain detected from the outbreak was carried out. The sequence analysis showed that the strain was genetically divergent from BRSV strains previously identified in Italy, as it showed high sequence similarity of more than 97% with strains isolated during a major BRSV epizootic that occurred in Sweden, Norway and Denmark during 2010–2011. The infection of the herd in Italy with this BRSV strain was likely due to the introduction of animals imported into Italy from abroad.
Bovine respiratory syncytial virus (BRSV) is an economically significant pathogen in cattle production. In Italy, although respiratory problems due to BRSV are frequently described, major outbreaks have not yet been reported. Here, we report an outbreak caused by a BRSV strain with high mortality that occurred in a dairy farm in Central Italy; this strain shows a sequence similarity of >97% to the strains isolated during a major BRSV epizootic that occurred in Sweden and Norway during 2010–2011. Epidemiological analysis indicated that recently introduced heifers from Germany were the likely carriers of the virus.
EHV1 and EHV4 are the most important herpesviruses in horses. Repeated cases of abortion in mares regularly vaccinated, prompted us to investigate the immune response after vaccination with the same ...inactivated vaccine, but with three different protocols. Eighteen mares were chosen and randomly divided in three study groups (G1-G2-G3) and a control group (Ctrl). For serologic and PCR investigations nasal swabs, sera and blood were collected. The protocol used in G3 (4 doses) increased the titer recorded by ELISA and seroneutralization (SN). Poor agreement and no correlation were observed in titer values between ELISA and SN and between SN and PCR. A very weak positive correlation between ELISA and PCR was obtained. Seven out of 18 nasal swabs were positive by PCR; none showed viremia and no abortion occurred, regardless of vaccination status and despite active circulation of EHV-1 in the farm at the time of the study. The study was conducted in field conditions, in a susceptible population with a known history of infection and abortion, and among the three protocols, the one proposed in the G1 was the least efficient while the one proposed for the G3, seems to have induced a higher antibody titer in both SN and ELISA.
Atypical porcine pestivirus (APPV) was recently reported to be associated with neurologic disorders in newborn piglets. Investigations of 1,460 serum samples of apparently healthy pigs from different ...parts of Europe and Asia demonstrate a geographically wide distribution of genetically highly variable APPV and high APPV genome and antibody detection rates.
Previous genetic characterization of African swine fever virus isolates from the Italian island of Sardinia, where the virus has been present since 1978, has largely been limited to a few selected ...genomic regions. Here, we report the complete genome sequence of the isolate 47/Ss/08 collected during an outbreak in 2008.
A novel hot-start multiplex PCR (mPCR) assay was developed and subsequently evaluated for its effectiveness in simultaneously detecting multiple viral infections of swine. Specific primers for each ...of five virus genomes, namely classical swine fever virus (CSFV), African swine fever virus (ASFV), porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV) and porcine parvovirus (PPV) were used. Combined nucleic acid purification was carried out using a commercial RNA/DNA extraction kit. The mPCR consisted of a two-step procedure which included reverse transcription and PCR amplification. This mPCR and the corresponding separate assays were evaluated comparatively on serial ten-fold dilutions of each virus. Analysis of the sensitivity in comparison to the corresponding single PCR (sPCR) for the detection of each of the five targets was identical for CSFV, PCV2 and PPV, 1 log lower for PRRSV and 2 logs lower for ASFV. No spurious PCR amplification reactions among all five pathogens were noticed with various amounts of DNA and RNA mixtures. All the uninfected controls were scored negative. The relative efficiency of the mPCR developed in this study compared to performing sPCR for each virus, suggests its potential application for routine molecular diagnostic purposes.
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