Comparative genomics of canine parvovirus in South America: Diversification patterns in local populations.

Canine parvovirus (CPV) is a significant pathogen in domestic dogs worldwide, causing a severe and often fatal disease. CPV comprises three antigenic variants (2a, 2b, and 2c) distributed unevenly among several phylogenetic groups. The present study compared genetic variability and evolutionary patterns in South American CPV populations. We collected samples from puppies suspected of CPV infection in the neighboring Argentina and Uruguay. Antigenic variants were preliminarily characterized using PCR-RFLP and partial vp2 sequencing. Samples collected in Argentina during 2008-2018 were mainly of the 2c variant. In the Uruguayan strains (2012-2019), the 2a variant wholly replaced the 2c from 2014. Full-length coding genome and vp2 sequences were compared with global strains. The 2c and 2a strains fell by phylogenetic analysis into two phylogroups (Europe I and Asia I). The 2c strains from Argentina and Uruguay clustered in the Europe I group, with strains from America, Europe, Asia, and Oceania. Europe I is widely distributed in South America in the dog population and is also being detected in the wildlife population. The 2a strains from Uruguay formed the distinct Asia I group with strains from Asia, Africa, America, and Oceania. This Asia I group is increasing its distribution in South America and worldwide. Our research reveals high genetic variability in adjacent synchronic samples and different evolutionary patterns in South American CPV. We also highlight the importance of ancestral migrations and local diversification in the evolution of global CPV strains.

Metronidazole-Induced Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) Syndrome With Parvovirus B19 Reactivation: A Pediatric Case.

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe and rare syndrome that causes life-threatening organ dysfunctions. Here, we present the case of a 10-year-old child who developed a pruritic erythematous eruption, fever, facial edema, and lymphadenopathy seven days after receiving intravenous metronidazole (20 mg/kg/day), vancomycin (50 mg/kg/day), and cefotaxime (200 mg/kg/day). Laboratory tests showed eosinophilia and liver damage as well as positive parvovirus B19 IgM and IgG indicating viral reactivation. Vancomycin was initially discontinued and later reintroduced with no ill effects. The patient was managed with topical corticosteroid emollients and cetirizine and improved within seven days of metronidazole withdrawal. Treatment with cefotaxime was continued and showed no adverse effects.

Investigation of canine parvovirus occurrence in cats with clinical signs of feline panleukopenia in Slovakia - pilot study.

Introduction: Feline panleukopenia is a contagious viral disease caused by the feline panleukopenia virus (FPV). A closely related pathogen is canine parvovirus (CPV), and amino acid substitutions in this virus allow it to acquire a feline host range. In feline hosts, the disease induced by CPV manifests with similar symptoms to those caused by FPV or milder ones, leading to its underdiagnosis. The aim of this study was to determine the presence of CPV type 2 (CPV-2) in cats with clinical symptoms of panleukopenia and to assess the use of commercial CPV antigen tests for the clinical diagnosis of FPV. Material and Methods: Samples from 59 cats from central Slovakia were included in the study. Rectal swabs were collected and clinically tested for parvovirus infection using a commercial antigen test. Antigen-positive samples were confirmed by PCR targeting the viral VP2 gene. The sequences of the PCR products were established with the Sanger method. Results: Of 59 samples, 23 were revealed to be positive for parvovirus infection by both antigen and PCR test (38.9%). Analysis with the National Center for Biotechnology Information BLASTn application showed 99.78-100% pairwise identity with FPV. The mortality rate of parvovirus-infected cats included in this study was 8.69% (2/23). Conclusion: Although feline disease with CPV-2 was not confirmed, the CPV antigen test was able to detect FPV infection.

Conjugation with the Carrier Helped to Reveal acidification-Induced Structural Shift in the Peptide from Phospholipase Domain of Parvovirus B19.

Spectroscopic studies on domains and peptides of large proteins are complicated because of the tendency of short peptides to form oligomers in aquatic buffers, but conjugation of a peptide with a carrier protein may be helpful. In this study we approved that a fragment of SK30 peptide from phospholipase A2 domain of VP1 Parvovirus B19 capsid protein (residues: 144-159; 164; 171-183; sequence: SAVDSAARIHDFRYSQLAKLGINPYTHWTVADEELLKNIK) turns from random coil to alpha helix in the acidic medium only in case if it had been conjugated with BSA (through additional N-terminal Cys residue, turning it into CSK31 peptide, and SMCC linker) according to CD-spectroscopy results. In contrast, unconjugated SK30 peptide does not undergo such shift because it forms stable oligomers connected by intermolecular antiparallel beta sheet, according to IR-spectroscopy, CD-spectroscopy, blue native gel electrophoresis and centrifugal ultrafiltration, as, probably, the whole isolated phospholipase domain of VP1 protein does. However, being a part of the long VP1 capsid protein, phospholipase domain may change its fold during the acidification of the medium in the endolysosome by the way of the formation of contacts between protonated His153 and Asp175, promoting the shift from random coil to alpha helix in its N-terminal part. This study opens up a perspective of vaccine development, since rabbit polyclonal antibodies against the conjugate of CSK31 peptide with BSA, in which the structure of the second alpha helix from the phospholipase A2 domain should be reproduced, can bind epitopes of the complete recombinant unique part of VP1 Parvovirus B19 capsid (residues: 1-227).

First identification of canine parvovirus -2a/2b variant in unvaccinated domestic dogs with gastrointestinal signs in Türkiye.

BACKGROUND: Canine parvovirus type 2 (CPV-2) is the most common enteric virus that infects canids. CPV is the causative agent of a contagious disease defined mostly by clinical gastrointestinal signs in dogs. During the late 1970s, CPV-2 emerged as a new virus capable of infecting domestic dogs and growing across the world. The VP2 gene stands out as a key determinant in the pathogenicity, antigenicity, and host interactions of CPV-2. AIMS: The molecular characterization of the VP2 gene is crucial for understanding CPV evolution and epidemiology. MATERIALS & METHODS: Genes encoding the VP2 protein were sequenced and compared to reference strains worldwide. The maximum likelihood method was used to build a phylogenetic tree using CPV VP2 gene nucleotide sequences. RESULTS: Our phylogenetic analysis of the VP2 gene revealed that five strains were very similar and clustered together, and three strains were in the 2b clade, whereas the other two were in the 2a/2b clade. DISCUSSION: This paper reports the molecular characterization of two novel CPV-2a/2b subtypes in dogs with gastrointestinal symptoms. Genetic analysis was conducted on a CPV genomic region encompassing one of the open reading frames (ORFs) encoding the structural protein VP2. Sequence analysis indicates new and unreported sequence changes, mainly affecting the VP2 gene, which includes the mutations Ser297Ala and Leu87Met. This study represents the first evidence of a new CPV-2a/2b subtype in Türkiye. Due to VP2's crucial role in encoding the capsid protein of CPV-2 and its significant involvement in the host-virus interaction, it is critical to closely monitor its evolutionary changes and be cautious while searching for novel or pre-existing subtypes. CONCLUSION: This study highlights the significance of continuous molecular research for acquiring more insights on the circulation of novel CPV mutants.

Genetic analysis of feline parvovirus reveals predominance of feline parvovirus -G1 group among cats in China.

Feline parvovirus (FPV) or feline panleukopenia virus is a highly contagious, life-threatening infectious virus in cats. Although FPV vaccination is routinely practiced in China, clinical diseases continue to occur. The investigation of genotypes and viral evolution can contribute to the prevention, diagnosis, and treatment of FPV. Therefore, this study aimed to provide an up-to-date understanding of the epidemiological, genotypic, and phylogenetic characteristics of FPV. In total, 152 rectal swabs were collected from diseased cats. All swab samples were tested for FPV using molecular methods. Amplification of the complete viral protein 2 (VP2) gene was performed for further analysis and to infer the genotypic and evolutionary characteristics of FPV. Of the 152 samples, FPV DNA was detected in 17 (17/152, 11.18%). Cats with FPV showed variable clinical signs such as dehydration, anorexia, fever, vomiting, and blood-stained diarrhea. Furthermore, VP2 sequences were identified in 17 PCR-positive cats, confirming the presence of FPV. Phylogenetic and nucleotide pairwise identity analyses revealed high genetic similarity among FPV sequences (99.6-100%) and clustered them into the FPV-G1 group. Amino acid analysis indicated a novel mutation (Ala91Ser) in all VP2 gene sequences amplified in this study. Our study provides baseline epidemiological data for the better prevention of FPV with respect to vaccination strategies. Genotypic and phylogenetic analyses confirm that FPV-G1 was the predominant FPV group in infected cats in Kunshan. Therefore, a rigorous countrywide investigation of the genotypic and evolutionary characteristics of FPV is warranted.

First Report of Porcine Parvovirus 8 in Europe: Widespread Detection and Genetic Characterization on Commercial Pig Farms in Hungary and Slovakia.

Porcine parvovirus 8 (PPV8), a novel virus in the Parvoviridae family, was first identified in 2022 in lung samples of domestic pigs from China. Retrospective analyses showed that it had been circulating in China since 1998, but no other countries had reported its presence so far. A recent study conducted in South America did not detect any PPV8-positive samples in that region. Here, we report the detection of PPV8 in Hungarian and Slovakian pig farms and the estimated prevalence of the virus in Hungary. Altogether, 2230 serum, 233 oral fluid, and 115 processing fluid samples were systematically collected from 23 Hungarian and 2 Slovakian pig farms between 2020 and 2023. A real-time quantitative PCR method was developed to detect the viral genome. Our results revealed the presence of PPV8 on 65% of the Hungarian farms and both Slovakian farms included in our study, marking its first detection in Europe. Oral fluid samples showed the highest positivity rates, reaching up to 100% in some herds. The viral genome was successfully detected in serum and processing fluid samples too, but with significantly lower prevalence rates of 4% and 5%, respectively. Genetic analysis of 11 partial VP2 sequences demonstrated high similarity to the original Chinese strain but with unique amino acid mutations, suggesting possible local evolution of the virus. Our study presents the first scientific evidence of PPV8 infection outside of China and offers a comprehensive assessment of its prevalence in the Hungarian pig population. Further research is required to understand its potential impact on swine health.

Molecular Detection of Viral and Bacterial Pathogens in Red Foxes (Vulpes vulpes) from Italy.

Animals, including wildlife, are part of One-Health concept since many infectious diseases can affect both humans and animals. In this study, 126 red foxes (Vulpes vulpes) from Northern Italy in 2022-2023 were tested by molecular assays for Protoparvovirus carnivoran 1 (PPVC-1), Canine adenovirus type 1 and 2 (CAdV-1 and CAdV-2), Circovirus canine (CanineCV), Canine distemper virus (CDV), and Leptospira spp. A total of 39 of 126 (30.9%) red foxes were infected with at least one pathogen and five of these were coinfected: 20/126 (15.9%) red foxes tested positive for PPVC-1, 3/126 (2.4%) for CAdV, 20/126 (15.9%) for CanineCV, and 2/126 (1.6%) for Leptospira spp. DNA. No foxes tested positive for CDV RNA. The pathogens identified were genetically analysed. New findings were reported such as a fox with multiple feline panleukopenia virus (FPV) and canine parvovirus type 2b (CPV-2b) infection associated with quasispecies dynamics, typical genetic characteristics of the identified CanineCV, and the first detection in red foxes of Leptospira ST198 related to L. interrogans serogroup Australis. Further studies are necessary to investigate the transmission between domestic animals and wildlife and to understand the role of red foxes in the maintenance of these pathogens not only in the wild but also in urban and peri-urban environments.

Reconstruction of the historic time course of blood-borne virus contamination of clotting factor concentrates, 1974-1992.

Factor VIII and IX clotting factor concentrates manufactured from pooled plasma have been identified as potent sources of virus infection in persons with hemophilia (PWHs) in the 1970s and 1980s. To investigate the range and diversity of viruses over this period, we analysed 24 clotting factor concentrates for several blood-borne viruses. Nucleic acid was extracted from 14 commercially produced clotting factors and 10 from nonremunerated donors, preserved in lyophilized form (expiry dates: 1974-1992). Clotting factors were tested by commercial and in-house quantitative PCRs for blood-borne viruses hepatitis A, B, C and E viruses (HAV, HBV, HCV, HEV), HIV- types 1/2, parvoviruses B19V and PARV4, and human pegiviruses types 1 and 2 (HPgV-1,-2). HCV and HPgV-1 were the most frequently detected viruses (both 14/24 tested) primarily in commercial clotting factors, with frequently extremely high viral loads in the late 1970s-1985 and a diverse range of HCV genotypes. Detection frequencies sharply declined following introduction of virus inactivation. HIV-1, HBV, and HAV were less frequently detected (3/24, 1/24, and 1/24 respectively); none were positive for HEV. Contrastingly, B19V and PARV4 were detected throughout the study period, even after introduction of dry heat treatment, consistent with ongoing documented transmission to PWHs into the early 1990s. While hemophilia treatment is now largely based on recombinant factor VIII/IX in the UK and elsewhere, the comprehensive screen of historical plasma-derived clotting factors reveals extensive exposure of PWHs to blood-borne viruses throughout 1970s-early 1990s, and the epidemiological and manufacturing parameters that influenced clotting factor contamination.

Epidemic of parvovirus B19 and disease severity in pregnant people, Denmark, January to March 2024.

We report an epidemic of parvovirus B19 infections in Denmark during the first quarter of 2024, with a peak incidence 3.5 times higher than during the most recent epidemic in 2017. In total, 20.1% (130/648) of laboratory-confirmed cases were pregnant. Severe adverse outcomes were observed among 12.3% (16/130) of pregnant people and included foetal anaemia, foetal hydrops and miscarriage. Parvovirus B19 infection is not systematically monitored, but a national laboratory-based surveillance system is currently being established in Denmark.

An unusual outbreak of parvovirus B19 infections, France, 2023 to 2024.

From April 2023 to May 2024, an unusual epidemic of parvovirus B19 (B19V) infections occurred in France. The number of B19V IgM-positive serologies was four times higher than in the previous epidemic in 2019. Clinical data from emergency networks corroborated this observation. Morbidity and mortality consequences were observed in children through all data sources. In adults, the increase was only observed in laboratory-confirmed data. Physicians and decisionmakers should be informed in order to better prevent, diagnose and manage at-risk patients.

Isolation and genetic characterization of waterfowl parvovirus in ducks in Northern Vietnam.

Background and Aim: Short beak and dwarfism syndrome (SBDS), a highly contagious disease, has been reported in duck farms in Vietnam since 2019. In this study, we evaluated the virulence and characterized the virus obtained from SBDS cases in North Vietnam. Materials and Methods: Polymerase chain reaction was used to detect waterfowl parvovirus in ducks, and the virus from positive samples was inoculated into 10-day-old duck-embryonated eggs to reproduce the disease in young ducklings to determine the virulence and subjected to phylogenetic analysis of non-structural (NS) and VP1 gene sequences. Results and Discussion: Goose parvovirus (GPV) was isolated from ducks associated with SDBS in Vietnam. The virus Han-GPV2001 is highly virulent when inoculated into 10-day-old duck embryos and 3-day-old ducklings. The mortality rate of duck embryos was 94.35% within 6 days of virus inoculation. Inoculating 3-day-old ducks with the virus stock with 104.03 EID50 through intramuscular and neck intravenous administration resulted in 80% and 66.67% of clinical signs of SDBS, respectively, were shown. Phylogenetic analysis based on the partial NS and VP1 gene sequences revealed that the viral isolate obtained in this study belonged to novel GPV (NGPV) and was closely related to previous Vietnamese and Chinese strains. Conclusion: A GPV strain, Han-GPV2001, has been successfully isolated and has virulence in duck-embryonated eggs as well as caused clinical signs of SBDS in ducks. Phylogenetic analyses of partial genes encoding NS and capsid proteins indicated that the obtained GPV isolate belongs to the NGPV group.

Splenic Sequestration Induced by Parvovirus B19: A Case Report.

Splenic sequestration crisis is a life-threatening complication of sickle cell disease (SCD), characterized by a sudden and huge accumulation of blood in the spleen, leading to rapid enlargement and may lead to organ failure. This case report discusses an unusual case of a splenic sequestration crisis in an adult with SCD. The patient's age, Parvovirus B19 infection, and concurrent retrocardiac pneumonia are all things that differentiate this case from our usual presentation. We will be discussing the clinical presentation, diagnostic methods, and management.

Recombination and amino acid point mutations in VP3 exhibit a synergistic effect on increased virulence of rMDPV.

Recombinant Muscovy duck parvovirus (rMDPV) is a product of genetic recombination between classical Muscovy duck parvovirus (MDPV) and goose parvovirus (GPV). The recombination event took place within a 1.1-kb DNA segment located in the middle of the VP3 gene, and a 187-bp sequence extending from the P9 promoter to the 5' initiation region of the Rep1 ORF. This resulted in the alteration of five amino acids within VP3. Despite these genetic changes, the precise influence of recombination and amino acid mutations on the pathogenicity of rMDPV remains ambiguous. In this study, based on the rMDPV strain ZW and the classical MDPV strain YY, three chimeric viruses (rZW-mP9, rZW-mPR187, and rYY-rVP3) and the five amino acid mutations-introduced mutants (rZW-g5aa and rYY-5aa(ZW)) were generated using reverse genetic technology. When compared to the parental virus rZW, rZW-g5aa exhibited a prolonged mean death time (MDT) and a decreased median lethal dose (ELD50) in embryonated duck eggs. In contrast, rYY-5aa(ZW) did not display significant differences in MDT and ELD50 compared to rYY. In 2-day-old Muscovy ducklings, infection with rZW-g5aa and rYY-5aa(ZW) resulted in mortality rates of only 20% and 10%, respectively, while infections with the three chimeric viruses (rZW-mP9, rZW-mPR187, rYY-rVP3) and rZW still led to 100% mortality. Notably, rYY-rVP3, containing the VP3 region from strain ZW, exhibited 50% mortality in 6-day-old Muscovy ducklings and demonstrated significant horizontal transmission. Collectively, our findings indicate that recombination and consequent amino acid changes in VP3 have a synergistic impact on the heightened virulence of rMDPV in Muscovy ducklings.

N6-methyladenosine modification of a parvovirus-encoded small noncoding RNA facilitates viral DNA replication through recruiting Y-family DNA polymerases.

Human bocavirus 1 (HBoV1) is a human parvovirus that causes lower respiratory tract infections in young children. It contains a single-stranded (ss) DNA genome of ~5.5 kb that encodes a small noncoding RNA of 140 nucleotides known as bocavirus-encoded small RNA (BocaSR), in addition to viral proteins. Here, we determined the secondary structure of BocaSR in vivo by using DMS-MaPseq. Our findings reveal that BocaSR undergoes N6-methyladenosine (m6A) modification at multiple sites, which is critical for viral DNA replication in both dividing HEK293 cells and nondividing cells of the human airway epithelium. Mechanistically, we found that m6A-modified BocaSR serves as a mediator for recruiting Y-family DNA repair DNA polymerase (Pol) η and Pol κ likely through a direct interaction between BocaSR and the viral DNA replication origin at the right terminus of the viral genome. Thus, this report represents direct involvement of a viral small noncoding RNA in viral DNA replication through m6A modification.

First detection of Tetraparvovirus ungulate 1 in diseased cattle (Chinese Simmental) from Hunan province, China.

Tetraparvovirus is an emerging parvovirus infecting a variety of mammals and humans, and associated with human diseases including severe acute respiratory infection and acute encephalitis syndrome. In the present study, a Tetraparvovirus ungulate 1 (formerly known as bovine hokovirus) strain HNU-CBY-2023 was identified and characterized from diseased Chinese Simmental from Hunan province, China. The nearly complete genome of HNU-CBY-2023 is 5346 nt in size and showed genomic identities of 85-95.5% to the known Tetraparvovirus ungulate 1 strains from GenBank, indicating a rather genetic variation. Phylogenetic and genetic divergence analyses indicated that Tetraparvovirus ungulate 1 could be divided into two genotypes (I and II), and HNU-CBY-2023 was clustered into genotype II. This study, for the first time, identified Tetraparvovirus ungulate 1 from domestic cattle from mainland China, which will be helpful to understand the prevalence and genetic diversity of Tetraparvovirus ungulate 1.

Molecular Characterization of the Chicken Parvovirus Based on VP1 Gene Circulating in Brazilian Chicken Flocks.

Parvovirus infection affects several animal species, especially young animals. In birds, parvovirus infection has been described in Muscovy ducks, turkeys, and chickens, all of which had enteric diseases characterized by diarrhea. Chicken parvovirus (ChPV) has been detected in poultry around the world in animals affected by enteric problems, showing dwarfism, cloacal pasting, and diarrhea. In Brazil, ChPV was detected in chickens affected by diarrhea fifteen years ago. However, the genetic characteristics of ChPV circulating in chicken flocks were not determined. Therefore, the aim of the present investigation was to determine the genetic characteristics of the VP1 gene from ChPV detected in chickens affected by enteric diseases in Brazil. For this purpose, a molecular approach was used. Specific primers were designed to flank the complete VP1 gene of ChPV and amplify it using PCR. The amplified products from samples of chickens with enteric diseases were sequenced, and 22 complete CDs of the VP1 gene were obtained. These samples, compared to the ABU-P1 sequence, showed 17 sequences with high nucleotide (NT) similarity of 92.7-97.4% and amino acid (AA) similarity of 94.8-99.5% associated with Runting and Stunting syndrome (RSS); there were also five samples associated with hens with diarrhea with unusual jejunal dilatation (JD) that had less similarity than the RSS sequences (NT of 86.5% and AA of 93-93.1%). The phylogenetic analysis determined four groups. Group I had sequences from Korea. The second group included sequences from Korea, China, and Brazil (not included in this work). The third group had studied RSS sequences grouped with the ABU-P1 strain and sequences from China and the United States. Finally, the sequences from JD were clustered in a separate group with a bootstrap of 100%, a group that was denoted as group IV, and included sequences from China. RDP4 and SimPlot analysis showed one point of recombination with the sequences of group III ChPV in the JD sequences. Herein, we show that circulating strains of ChPV exhibit genetic differences in the VP1 gene in Brazilian chicken flocks. Nevertheless, more studies are needed to determine the probability of a new genetic group of ChPV based on the analysis of the complete genome.

Canine Amniotic Fluid at Birth Holds Information about Neonatal Antibody Titres against Core Vaccine Viruses.

There is a growing interest in the composition of amniotic fluid (AF) in both humans and animals. In addition to its nutritional and protective functions for the foetus, current knowledge demonstrates that AF also serves advanced diagnostic, prognostic, and therapeutic roles. Newborn dogs have an underdeveloped immune system, making them highly susceptible to dangerous pathogens such as canine parvovirus (CPV-2), canine infectious hepatitis virus (CAdV-1), and canine distemper virus (CDV), thus exposing them to a high risk of mortality in the first weeks of life. Immunoglobulins G (IgGs) represent the only antibody isotype capable of crossing the placenta in a small amount and have been detected also in canine AF. The primary aim of this study was to investigate the reliability of AF collected at birth as a marker of passive immunity in canine species. For this purpose, total and specific IgGs against CPV-2, CAdV-1, and CDV were investigated and quantified in both maternal plasma and AF collected at the time of caesarean section. The vaccination status of the bitches was also taken into consideration. Since the immune system can be influenced by gestational age, with preterm infants having immature innate and adaptive immunity, IgG concentrations were correlated with amniotic lecithin, sphingomyelin, cortisol, surfactant protein A, and pentraxin 3 levels. In a previous study from our group on foetal maturity these molecules were measured in the same samples. Finally, correlations between their amniotic content and neonatal outcomes were investigated. This study demonstrates that AF analysis at birth can provide valuable insights into neonatal immunity in puppies, offering a non-invasive method to detect potential early health risks, for improved puppy care and management.

First Molecular Characterisation of Porcine Parvovirus 7 (PPV7) in Italy.

Porcine parvoviruses (PPVs) are among the most important agents of reproductive failure in swine worldwide. PPVs comprise eight genetically different species ascribed to four genera: Protoparvovirus (PPV1, PPV8), Tetraparvovirus (PPV2-3), Copiparvovirus (PPV4-6), and Chaphamaparvovirus (PPV7). In 2016, PPV7 was firstly detected in the USA and afterwards in Europe, Asia, and South America. Recently, it was also identified in Italy in pig farms with reproductive failure. This study aimed to evaluate the circulation of PPV7 in domestic and wild pigs in Sardinia, Italy. In addition, its coinfection with Porcine Circovirus 2 (PCV2) and 3 (PCV3) was analysed, and PPV7 Italian strains were molecularly characterised. PPV7 was detected in domestic pigs and, for the first time, wild pigs in Italy. The PPV7 viral genome was detected in 20.59% of domestic and wild pig samples. PPV7 detection was significantly lower in domestic pigs, with higher PCV2/PCV3 co-infection rates observed in PPV7-positive than in PPV7-negative domestic pigs. Molecular characterisation of the NS1 gene showed a very high frequency of recombination that could presumably promote virus spreading.