Detection of hepatitis E virus in faeces and liver of pigs collected at two Slovenian slaughterhouses

In recent years there have been numerous reports from different parts of the world describing hepatitis E virus (HEV) as a zoonotic agent, but the clinical cases in humans are still reported only sporadically. Domestic pigs represent the main reservoir of the HEV. Until recently it was believed that the HEV was transmitted only by faecal-oral route, but it has been proved that eating raw or undercooked pork meat and offal can cause acute HEV infection in human. This has triggered the alarm and many developed countries have already done a few studies to assess the percentage of infected pigs.In this study the situation regarding the risk factor of HEV among pigs that enter the food chain in Slovenia was evaluated. At two different slaughterhouses 87 faeces and liver samples were collected from pigs within two age groups. 32 faeces and liver samples were collected from 3 months old pigs and 55 faeces and liver samples from 6 months old pigs. Animals were brought to the slaughterhouse from different farms located at the north eastern part of Slovenia, where the majority of the pig population is located. Collected samples were analysed with real-time RT-PCR method. Nucleic acids of HEV was found in 6 faeces samples from the younger age group (3 months of age), which represents 19% of examined samples. All liver samples from 3 months old pigs were negative. All samples of faeces and liver from 6 month old pigs were negative. The results were comparable with those from other European countries, where 7-30% of swine faeces samples were found HEV positive

Variations in the detection of anti-PEDV antibodies in serum samples using three diagnostic tests – short communication

Over the last few years several porcine epidemic diarrhoea (PED) outbreaks have been discovered in Europe including the first PED case in Slovenia in January 2015. The aim of this study was to determine when PED virus (PEDV) infection started in Slovenia. Serum samples collected between 2012 and 2016 were tested. Three hundred and seventy-five serum samples were collected from 132 Slovenian small, one-site pig farms. Samples were tested for PEDV antibodies utilising three different serological methods: commercially-available indirect ELISA, in-house blocking ELISA test and Immunoperoxidase Monolayer Assay (IPMA) test. One hundred and seventy (45.33%) tested samples were found positive by the commercially-available ELISA test kit, and 10 (5.68%) of these 170 samples found positive were positive by the in-house blocking ELISA. Only these 10 samples were collected from a farm where clinical signs of PED infection had been observed and PEDV was confirmed by RT-PCR methodology; the other 160 samples were collected randomly. Thirty-two samples with the highest S/P value obtained with the commercial ELISA were all negative with IPMA. Reasons for the high variance in the results obtained remain unclear; more research is required to ensure higher sensitivity and specificity in terms of PEDV antibody tests and other PED diagnostic methods

Serum inoculation as a possibility for elimination of porcine reproductive and respiratory syndrome (PRRS) from a farrow-to-finish pig farm

The large heterogeneity among porcine reproductive and respiratory syndrome virus (PRRSV) isolates is probably the main obstacle to its effective control using current commercial vaccines. Intentionally exposing all breeding pigs to PRRSV circulating on the farm could eliminate porcine reproductive and respiratory syndrome (PRRS) from the herd. The objective of this study was to eliminate PRRS from a farrow-to-finish pig farm by serum inoculation. The owner was acquainted with the strict biosecurity measures. Breeding pigs were immunised with serum, which was obtained from PRRSV-positive weaners from the same farm. The percent of antibody high positive breeding pigs decreased six months after serum inoculation, while 34 months after serum inoculation no more antibody high positive pigs were detected and 56.8% of breeding pigs and all other categories were free of antibodies. In the breeding herd no virus was detected during all testing while PRRSV circulated in 2-month-old weaners until 12 months after serum inoculation. Later all tested samples from weaners, growers and fatteners were negative. Herd closure and the adoption of strict biosecurity measures are essential. Serum inoculation of the breeding herd proved to be a successful measure for eliminating PRRS from this farrow-to-finish farm

Kontrola arteritisa konja na jednoj ergeli.

An epidemiology of infection with equine arteritis virus (EAV) on one stud farm with approximately 350 horses in the period from 1995 to 2008 was studied. Infection was detected by virological methods, using a virus neutralisation test (VNT) for EAV antibody detection in serum samples, and virus isolation and RT-PCR test for virus detection in semen. No clinical picture of the disease was observed. The highest seroprevalence (nearly 100%) was among stallions and old mares, while seroprevalence among young fi llies, before mating, was lower than 9%. A high incidence for seroconversion was detected among fi llies after mating. Virus was detected by RT-PCR and by a virus isolation test in the semen of 40.7% of 76 seropositive stallions. The 8 stallions, which were shedding EAV, were infected within the period of the first three years after birth, but the other 12 seropositive stallions, which were negative for EAV in semen samples, became firstly seropositive 5 years after birth. In this study we confirmed that the major transmission of EAV on the stud farm occurred from shedding stallions to fillies during the mating time, but an important role of virus transmission to other horses is also played by contact between different groups of animals. Virus positive stallions were castrated and a new breeding unit for young foals was established. EAV negative foals were vaccinated and were bred outside the farm up to 3 years of age.Prikazana je epizootiologija arteritisa konja na jednoj ergeli s 350 konja u razdoblju od 1995. do 2008. godine. Zaraza je bila dokazana na osnovi serološke pretrage virus neutralizacijskim testom (VNT), izdvajanja i identifikacije virusa te RT-PCR-om u sjemenu pastuha. Klinički znakovi bolesti nisu bili primijećeni. Najveća seroprevalencija (gotovo 100%) bila je dokazana u pastuha i starih kobila dok je seroprevalencija u ždrjebica prije pripusta bila manja od 9%. Visoka incidencija serokonverzije bila je dokazana u ždrjebica nakon pripusta. Virus je bio dokazan RT-PCR-om i izdvojen iz sjemena 40,7% od 76 serološki pozitivnih pastuha. Osam pastuha koji su izlučivali virus arteritisa bilo je zaraženo u prvim trima godinama života, a ostalih 12 serološki pozitivnih u kojih virus nije bio izdvojen iz sjemena postali su prvi put serološki pozitivni pet godina nakon ždrijebljenja. Potvrđeno je da se virus u najvećoj mjeri prenosio s pastuha koji su izlučivali virus na ždrjebice za vrijeme pripusta. Za prijenos virusa važan je bio i izravan dodir među različitim skupinama životinja. Pastusi pozitivni na virus bili su kastrirani te je osnovana nova uzgojna jedinica za ždrebad. Ždrebad negativna na virus arteritisa bila je cijepljena, a do treće godine držana izvan ergele

The silent spread of Porcine Bocavirus in Croatian pigs: should we be concerned?

A survey was conducted to evaluate the presence and prevalence of Porcine Bocavirus (PBoV) in Croatian domestic pigs by means of PCR targeting the NS1 gene fragment of PBoV. This study included testing of faecal samples collected from 10 small commercial farms and 11 small backyard holdings in Croatia. The presence of PBoV was confirmed by PCR in 24 out of 57 composite faecal samples from small commercial farms and in 12 out of 43 composite faecal samples from small backyard holdings. The PCR products of 18 positive samples were sequenced for genotyping. PBoV sequences grouped into the PBoV-a, PBoV-b and PBoV-c groups with 90.81% to 99.25% nucleotide identity. All Croatian PBoV sequences showed a high nucleotide and amino acid identity with PBoV sequences from China and Hong Kong, the United States, Sweden, and Slovenia. These results clearly show that PBoV is circulating among the domestic pig population in Croatia

Genomic determinants of Furin cleavage in diverse European SARS-related bat coronaviruses

The furin cleavage site (FCS) in SARS-CoV-2 is unique within the Severe acute respiratory syndrome-related coronavirus (SrC) species. We re-assessed diverse SrC from European horseshoe bats and analyzed the spike-encoding genomic region harboring the FCS in SARS-CoV-2. We reveal molecular features in SrC such as purine richness and RNA secondary structures that resemble those required for FCS acquisition in avian influenza viruses. We discuss the potential acquisition of FCS through molecular mechanisms such as nucleotide substitution, insertion, or recombination, and show that a single nucleotide exchange in two European bat-associated SrC may suffice to enable furin cleavage. Furthermore, we show that FCS occurrence is variable in bat- and rodent-borne counterparts of human coronaviruses. Our results suggest that furin cleavage sites can be acquired in SrC via conserved molecular mechanisms known in other reservoir-bound RNA viruses and thus support a natural origin of SARS-CoV-2

Emerging trends in the epidemiology of West Nile and Usutu virus infections in Southern Europe

The epidemiology of West Nile (WNV) and Usutu virus (USUV) has changed dramatically over the past two decades. Since 1999, there have been regular reports of WNV outbreaks and the virus has expanded its area of circulation in many Southern European countries. After emerging in Italy in 1996, USUV has spread to other countries causing mortality in several bird species. In 2009, USUV seroconversion in horses was reported in Italy. Co-circulation of both viruses was detected in humans, horses and birds. The main vector of WNV and USUV in Europe is Culex pipiens, however, both viruses were found in native Culex mosquito species (Cx. modestus, Cx. perexiguus). Experimental competence to transmit the WNV was also proven for native and invasive mosquitoes of Aedes and Culex genera (Ae. albopictus, Ae. detritus, Cx. torrentium). Recently, Ae. albopictus and Ae. japonicus naturally-infected with USUV were reported. While neuroinvasive human WNV infections are well-documented, USUV infections are sporadically detected. However, there is increasing evidence of a role of USUV in human disease. Seroepidemiological studies showed that USUV circulation is more common than WNV in some endemic regions. Recent data showed that WNV strains detected in humans, horses, birds, and mosquitoes mainly belong to lineage 2. In addition to European USUV lineages, some reports indicate the presence of African USUV lineages as well. The trends in WNV/USUV range and vector expansion are likely to continue in future years. This mini-review provides an update on the epidemiology of WNV and USUV infections in Southern Europe within a multidisciplinary "One Health" context