ABSTRACT
The recent reinforcement of CoV surveillance in animals fuelled by the COVID-19 pandemic provided increasing evidence that mammals other than bats might hide further diversity and play critical roles in human infectious diseases. This work describes the results of a two-year survey carried out in Italy with the double objective of uncovering CoV diversity associated with wildlife and of excluding the establishment of a reservoir for SARS-CoV-2 in particularly susceptible or exposed species. The survey targeted hosts from five different orders and was harmonised across the country in terms of sample size, target tissues, and molecular test. Results showed the circulation of 8 CoV species in 13 hosts out of the 42 screened. Coronaviruses were either typical of the host species/genus or normally associated with their domestic counterpart. Two novel viruses likely belonging to a novel CoV genus were found in mustelids. All samples were negative for SARS-CoV-2, with minimum detectable prevalence ranging between 0.49% and 4.78% in the 13 species reaching our threshold sample size of 59 individuals. Considering that within-species transmission in white-tailed deer resulted in raising the prevalence from 5% to 81% within a few months, this result would exclude a sustained cycle after spillback in the tested species.
Subject(s)
COVID-19 , Chiroptera , Deer , One Health , Animals , Humans , Animals, Wild , COVID-19/epidemiology , COVID-19/veterinary , SARS-CoV-2 , PandemicsABSTRACT
Aujeszky's disease in cattle is caused by Suid herpes virus 1. The natural infection has been reported worldwide in bovine species and it is related to direct and indirect contact with infected pigs, which represent the main reservoir of the virus. Here, it is reported the first documented outbreak of Aujeszky's disease in cattle in Sicily (Italy). Severe itching and nonspecific neurological symptoms were the main reported clinical signs. No characteristic gross and histological features were reported other than cutaneous lesions caused by excessive pruritus and hyperaemia, haemorrhages and inflammation in the central nervous system. Diagnosis was confirmed by real time PCR and immunohistochemistry on the nervous tissue. The route of infection remained unknown, but serological data observed in pigs living in close cohabitation with cattle revealed a circulation of a wild strain of the virus in the area. This study contributes to a better knowledge of this disease in a non-conventional host and suggests the need to increase the prophylaxis control plans in specific breeding contexts.
ABSTRACT
The genus Pestivirus comprises globally distributed members of the family Flaviviridae, which cause severe losses in livestock. The most common species of the genus are bovine viral diarrhoea virus type 1 (BVDV-1) and type 2 (BVDV-2), classical swine fever virus (CSFV) and border disease virus (BDV). Recently, a novel ovine pestivirus was repeatedly detected in aborted lamb foetuses on a farm located in the Brescia Province (Italy). Complete genome characterization of this isolate showed that it was highly divergent from known pestivirus species and that it was genetically closely related to CSFV. The aim of this study was to determine the serological relatedness between the identified novel pestivirus and BVDV, BDV and CSFV selected strains for which homologous serum was available, by antigenic characterization performed using cross-neutralization assays. The serological relatedness was expressed as the coefficient of antigenic similarity (R). Both field and specific antisera raised against the ovine pestivirus neutralized the CSFV reference strain Diepholz with titres significantly higher than those specific for the BDV and BVDV strains. Furthermore, the calculated R values clearly indicated that the novel ovine pestivirus is antigenically more related to CSFV than to ruminant pestiviruses, in agreement with the results of the genomic analysis. This would have severe consequences on CSFV serology in the event of a switch to porcine hosts with implications for CSFV surveillance and porcine health management.
Subject(s)
Classical Swine Fever/virology , Pestivirus/genetics , Sheep Diseases/virology , Animals , Classical Swine Fever/epidemiology , Italy/epidemiology , Pestivirus/classification , Ruminants/virology , Sheep , Sheep Diseases/epidemiology , SwineABSTRACT
Although the eradication of Pseudorabies virus (PrV) in domestic pigs is ongoing, the circulation of this virus in wild boars remains a threat in the currently unprotected, 'low prevalence', pig population. In this study, we reported PrV prevalence data and the influence of possible risk factors in 2 North-West Italian wild boar populations (free and enclosed) with the goal of supporting the implementation of a risk-based AD surveillance system. Sera from 1,425 wild boars were collected between 2011 and 2015 and tested by ELISA for the presence of PrV antibodies; the overall raw seroprevalence was 30.39% (433/1,425; CI 95% 28.01-32.85%). A significant difference was however observed between the prevalence rates of the free range population (9.98%; 90/902; CI 95%; 8.10-12.12%) and the enclosed population of La Mandria park (Piedmont, Italy) (65.58%; 343/523; CI 95%; 61.51-69.65%). In both populations a significantly higher number of adults and females were found positive to PrV ELISA. Specific territorial data on PrV circulation in wild boars should be acquired from other regions for guiding risk-based measures in order to reduce the threat of AD re-infection in a more cost-effective manner.
Subject(s)
Epidemiological Monitoring/veterinary , Herpesvirus 1, Suid/isolation & purification , Pseudorabies/epidemiology , Swine Diseases/epidemiology , Animals , Italy/epidemiology , Prevalence , Pseudorabies/virology , Risk Factors , Seroepidemiologic Studies , Sus scrofa , Swine , Swine Diseases/virologyABSTRACT
Sixteen haemagglutinin (HA) subtypes of avian influenza viruses (AIV) have been described to date. Rapid subtype identification of any AIV is of major interest because of the possible serious consequences for the poultry industry and even public health. Molecular techniques currently allow immediate accurate subtype characterisation prior to virus isolation. In this study, a set of fourteen specific real-time RT-PCR methods were developed and evaluated for AIV HA subtyping (H1-H4, H6-H8, H10-H16), H5 and H9 being excluded on the basis of the current validity of the European Union (EU) recommended specific assays. Specific primers and probes sets for each HA-subtype were designed to hybridise the largest isolates range within each single subtype, considering the Eurasian lineage as a major target. The robustness and general application of the 14 HA-subtype methods were verified by the analysis of 110 AIV isolates belonging to all 16 HA-subtypes, performed in different laboratories. The developed real-time RT-PCR assays proved to be highly specific and revealed suitable sensitivity, allowing direct HA-subtyping of clinical material. In summary, this study provides for the first time a panel of molecular tests using specific hydrolysis probes for rapid and complete AIV HA-subtype identification.