Porcine Respirovirus 1 (PRV1) is an enveloped, single-stranded, negative-sense RNA virus belonging to the genus Respirovirus within the Paramyxoviridae family. Since its first detection in China in 2013, PRV1 has been identified in several American and European countries. Although its pathogenicity is uncertain, recent studies have suggested that it may play a role in the Porcine Respiratory Disease Complex (PRDC) because of its capacity to replicate in the upper and lower respiratory tracts. This study aimed to determine the spread of PRV1 in Northern Italy and the phylogeny of the isolates. Therefore, PRV1 was investigated using real-time RT-PCR in 902 samples collected from September 2022 to September 2023 from pigs with respiratory symptoms in North Italy. Fourteen (1.55%) samples tested as PRV1-positive. The full-length fusion (F) gene, which codifies for a major surface protein, was amplified and used for phylogenetic analysis to help carry out molecular epidemiological studies on this virus. In addition, swine influenza virus (SIV) and porcine reproductive and respiratory syndrome virus (PRRSV) infections were detected in most of the PRV1-positive samples. In conclusion, we report the detection of PRV1 in Italy and discuss its potential role as a co-factor in causing the Porcine Respiratory Disease Complex.

Over the last few decades, several pestiviruses have been discovered in ruminants, pigs, and, more recently, in non-ungulate hosts. Consequently, the nomenclature and taxonomy of pestiviruses have been updated. The Tunisian sheep-like pestivirus (TSV, Pestivirus N) is an additional ovine pestivirus genetically closely related to classical swine fever virus (CSFV). In this study, during a survey of pestivirus infections in ovine farms in the Lombardy region of Northern Italy, we identified and isolated a pestivirus strain from a sheep that was found to belong to Pestivirus N species based on its genomic nucleotide identity. The sheep itself and its lamb were found to be persistently infected. We performed molecular characterization and phylogenetic analysis of three viral genomic regions (a fragment of 5′-UTR, partial N^pro, and the whole E2 region). In conclusion, these results confirmed circulating TSV in Northern Italy after notification in Sicily, Italy, and France. Correlation with Italian, Tunisian, and French strains showed that detection might have resulted from the trading of live animals between countries, which supports the need for health control measures.

Bovine viral diarrhea (BVD) is a major cause of economic losses in the global cattle industry, particularly in countries characterized by intensive livestock production systems. Pestivirus tauri, formerly known as Bovine viral diarrhea virus type 2 (BVDV-2), is the current taxonomic designation according to the International Committee on Taxonomy of Viruses (ICTV). Between 2005 and 2018, Pestivirus tauri was detected in cattle herds in mainland Italy, particularly in the Lombardy region. Four viral strains were successfully isolated in cell cultures and subjected to whole-genome sequencing. Phylogenetic reconstruction placed all Italian isolates within the Pestivirus tauri subgenotype c, a lineage encompassing strains reported in Asia, Europe and the United States. Consistently, comparative sequence identity analyses indicated the highest similarity with the Parker strain (USA, 1991) and the Potsdam 1600 strain (Germany, 2000). These results contribute to a more detailed understanding of Pestivirus tauri genomic architecture and evolutionary dynamics, providing a valuable resource for comparative genomic studies. Such data are crucial for exploring viral diversity and evolution, optimizing the design of diagnostic primers and probes, and advancing insights into the molecular epidemiology of Pestivirus.