Circulation of canine parvovirus among dogs living in human-wildlife interface in the Atlantic forest biome, Brazil

Molecular characterization of carnivore protoparvovirus 1 circulating in domestic carnivores in Egypt

Canine parvovirus (CPV) and feline panleukopenia virus (FPV), now included in the unique species Carnivore protoparvovirus 1 (CPPV1), have been circulating in dogs and cats for several decades and are considered the causes of clinically important diseases, especially in young animals. While genetic evidence of the circulation of parvoviruses in Egyptian domestic carnivores has been provided since 2016, to date, all available data are based on partial fragments of the VP2 gene. This study reports the molecular characterization of CPPV strains from Egypt based on the full VP2 gene. Overall, 196 blood samples were collected from dogs and cats presented at veterinary clinics for routine medical assessment in 2019 in Egypt. DNA extracts were screened and characterized by real-time PCR. Positive samples were amplified by conventional PCR and then were sequenced. Nucleotide and amino acid changes in the sequences were investigated and phylogeny was inferred. Carnivore protoparvovirus DNA was detected in 18 out of 96 dogs (18.8%) and 7 of 100 cats (7%). Phylogenetic analyses based on the full VP2 gene revealed that 9 sequenced strains clustered with different CPV clades (5 with 2c, 2 with 2a, 1 with 2b, and 1 with 2) and 1 strain with the FPV clade. All three CPV variants were detected in dog and cat populations with a predominance of CPV-2c strains (7 of 18, 38.9%) in dog samples, thus mirroring the circulation of this variant in African, European, and Asian countries. Deduced amino acid sequence alignment revealed the presence of the previously unreported unique mutations S542L, H543Q, Q549H, and N557T in the Egyptian CPV-2c strains.

Detection and Genetic Characterization of Canine Adenoviruses, Circoviruses, and Novel Cycloviruses From Wild Carnivores in Italy

Wild carnivores are known to play a role in the epidemiology of several canine viruses, including canine adenoviruses types 1 (CAdV-1) and 2 (CAdV-2), canine circovirus (CanineCV) and canine distemper virus (CDV). In the present study, we report an epidemiological survey for these viruses in free ranging carnivores from Italy. A total of 262 wild carnivores, including red foxes (Vulpes vulpes), wolves (Canis lupus) and Eurasian badgers (Meles meles) were sampled. Viral nucleic acid was extracted and screened by real-time PCR assays (qPCR) for the presence of CAdVs and CanineCV DNA, as well as for CDV RNA. CAdV-1 DNA was detected only in red foxes (4/232, 1.7%) whilst the wolves (0/8, 0%) and Eurasian badgers (0/22, 0%) tested negative. CanineCV DNA was detected in 4 (18%) Eurasian badgers, 4 (50%) wolves and 0 (0%) red foxes. None of the animals tested positive for CDV or CAdV-2. By sequence and phylogenetic analyses, CAdV-1 and CanineCV sequences from wild carnivores were closely related to reference sequences from domestic dogs and wild carnivores. Surprisingly, two sequences from wolf intestines were identified as cycloviruses with one sequence (145.20-5432) displaying 68.6% nucleotide identity to a cyclovirus detected in a domestic cat, while the other (145.201329) was more closely related (79.4% nucleotide identity) to a cyclovirus sequence from bats. A continuous surveillance in wild carnivores should be carried out in order to monitor the circulation in wildlife of viruses pathogenic for domestic carnivores and endangered wild species.

Molecular phylogenetic assessment of the canine parvovirus 2 worldwide and analysis of the genetic diversity and temporal spreading in Brazil

Canine parvovirus type 2 (CPV-2) is a relevant pathogen for dogs and causes a severe disease in carnivore species. CPV-2 reached pandemic proportions after the 1970s with the worldwide dissemination, generating antigenic and genetic variants (CPV-2a, CPV-2b, and CPV-2c) with different pathobiology in comparison with the original type CPV-2. The present study aimed to assess the current global CPV-2 molecular phylogeny and to analyze genetic diversity and temporal spreading of variants from Brazil. A total of 284 CPV-2 whole-genome sequences (WGS) and 684 VP2 complete genes (including 23 obtained in the present study) were compared to analyze phylogenetic relationships. Bayesian coalescent analysis estimated the time to the most recent common ancestor (tMRCA) and the population dynamics of the different CPV-2 lineages in the last decades. The WGS phylogenetic tree demonstrated two main clades disseminated worldwide today. The VP2 gene tree showed a total of four well-defined clades distributed in different geographic regions, including one with CPV-2 sequences exclusive from Brazil. These clades do not have a relationship with the previous classification into CPV-2a, CPV-2b, and CPV-2c, despite some having a predominance of one or more antigenic types. Temporal analysis demonstrated that the main CPV-2 clades evolved within a few years (from the 1980s to 1990s) in North America and they spread worldwide afterwards. Population dynamics analysis demonstrated that CPV-2 presented a major dissemination increase at the end of the 1980s / beginning of the 1990s followed by a period of stability and a second minor increase from 2000 to 2004.

Canine parvovirology - A brief updated review on structural biology, occurrence, pathogenesis, clinical diagnosis, treatment and prevention

Canine parvovirus (CPV) is a major cause of hemorrhagic diarrhea and mortality in puppies worldwide. There are 2 types of Parvovirus which affects canines: Canine parvovirus 2 (CPV-2) and Canine parvovirus 1 (CPV-1) or the Minute Virus of Canine (MVC). CPV-2 originated from Feline panleukopenia virus and has undergone genetic variation to give rise to its three variants (CPV-2a, CPV-2b and CPV-2c). Amino acid substitutions in VP2 capsid protein have led virus to adapt new host range. The original CPV-2 was known to be dominant in Japan, Belgium, Australia as well as USA and later circulated throughout the world. Clinically, CPV-2 infection is characterized by anorexia, lethargy, depression, vomiting, leukopenia and severe hemorrhagic diarrhea. Several diagnostic tests have been developed to detect parvoviral infections which are categorized into immunological tests (latex agglutination test, SIT-SAT and ELISA etc.) and molecular based tests (PCR, mPCR and RT-PCR etc.). To control and manage the disease several treatments like fluid therapies, antibiotics, and adjunctive treatments are available and some are in various stages of development. Apart from this, many vaccines are also commercially available and some are in developmental stages. The present review contains detailed information regarding structural biology, occurrence, pathogenesis, clinical diagnosis, treatments and prevention in order to understand the need and the growing importance of CPV-2.

Risk and Environmental Factors Associated with the Presence of Canine Parvovirus Type 2 in Diarrheic Dogs from Thessaly, Central Greece

Canine parvovirus type 2 (CPV-2) primarily infects dogs, which are the main host reservoir, causing severe gastrointestinal disease associated with immunosuppression. The present study was conducted in Thessaly, Greece and aimed to identify risk and environmental factors associated with CPV-2 infection in diarrheic dogs. Fecal samples were collected from 116 dogs presenting diarrhea and were tested by polymerase chain reaction (PCR) for the presence of CPV-2 DNA. Supplementary data regarding clinical symptoms, individual features, management factors and medical history were also gathered for each animal during clinical evaluation. Sixty-eight diarrheic dogs were found to be positive for the virus DNA in their feces. Statistical analysis revealed that CPV-2 DNA was less likely to be detected in senior dogs, while working dogs, namely hounds and shepherds, had higher odds to be positive for the virus. Livestock density and land uses, specifically the categories of discontinuous urban fabric and of human population density, were identified as significant environmental parameters associated with CPV-2 infection by using Geographical Information System (GIS) together with the Ecological Niche Model (ENM). This is the first description of the environmental variables associated with the presence of CPV-2 DNA in dogs’ feces in Greece.

Circulation of diverse protoparvoviruses in wild carnivores, Italy

Protoparvovirus is a monophyletic viral genus that includes the species Carnivore protoparvovirus-1 infecting domestic and wild carnivores. In this paper, the results of an epidemiological survey for Carnivore protoparvovirus-1 in wild carnivores in Italy are reported. Overall, 34 (11.4%) out of 297 tested animals were positive for Carnivore protoparvovirus-1, but the frequency of detection was much higher in intestine (54%) than in spleen samples (2.8%), thus suggesting that the intestine is the best sample to collect from wild animals for parvovirus detection. Feline panleukopenia virus (FPV) was detected in red foxes (Vulpes vulpes) (2.8%, 7/252) and Eurasian badgers (Meles meles) (10%, 1/10), whilst canine parvovirus (CPV) was found in wolves (54.3%, 19/35), Eurasian badgers (60%, 6/10) and one beech marten (Martes foina) (100%, 1/1), with more than one parvovirus type detected in some animals. Protoparvoviral DNA sequences from this study were found to be related to CPV/FPV strains detected in Asia and Europe, displaying some amino acid changes in the main capsid protein VP2 in comparison with other parvovirus strains from wildlife. In particular, the two most common mutations were Ile418Thr and Ala371Gly, which were observed in 6/12 (50%) and 5/12 (41.7%) of the CPV sequences from this study. Continuous surveillance for parvoviruses in wild carnivores and genetic analysis of the detected strains may help obtain new insight into the role of these animals in the evolution and epidemiology of carnivore parvoviruses.

Detection of canine parvovirus types 2b and 2c in canine faecal samples contaminating urban thoroughfares in Brazil

Canine parvovirus type 2 (CPV-2) is a highly contagious virus that causes acute gastroenteritis in dogs all over the world. Because of its stability in the environment, CPV-2 can remain infective for a long time, especially if protected in organic matter. To demonstrate CPV-2's potential as an environmental hazard for nonimmunized susceptible hosts, we investigated 50 faecal samples collected from public areas in a municipality of Paraná state, Brazil. Seven samples tested positive for CPV by a PCR assay targeting the partial VP2 gene, with three strains being confirmed as CPV-2b variant and one as CPV-2c variant by sequence analysis. These findings were supported by phylogenetic analysis, and the species identity of faecal samples source was confirmed by canine mitochondrial DNA amplification and sequencing. Our results demonstrate the presence of CPV in canine faeces contaminating urban thoroughfares and reinforce the importance of environmental control to reduce the potential exposure risks to susceptible hosts.

The triad "dogs, conservation and zoonotic diseases" - An old and still neglected problem in Brazil

The presence of domestic/free-ranging dogs in Brazilian protected areas and native vegetation fragments is an important problem, mainly because these animals pose a threat to wild species that live in such areas. In addition, dogs constantly circulate between wildlife environments and urban regions, acting as "bridges" in spillover events. Dogs are traditionally recognized as vectors of zoonoses, which are correct, but their roles as facilitating agents for the "jump" of pathogens from wild animals to humans (and vice versa) are sparsely debated. In this context, this work briefly describes the different roles of dogs in the dynamics and ecology of infectious diseases, using the Brazilian scenario as a study model.

ABSENCE OF PARVOVIRUS SHEDDING IN FECES OF THREATENED CARNIVORES FROM MISIONES, ARGENTINA

Since its emergence in the 1970s, canine parvovirus (CPV) has spread worldwide and infects a wide variety of mammalian hosts, including domestic and nondomestic carnivores. Today it is one of the most important pathogenic viruses associated with high morbidity and mortality in domestic dogs ( Canis familiaris). In South America, the range of wild hosts has been scarcely studied and the epidemiology of CPV in wildlife is still unclear. In 2011, feces from five wild carnivores (bush dog [ Speothos venaticus] , jaguar [ Panthera onca], puma [ Puma concolor], oncilla [ Leopardus guttulus], and ocelot [ Leopardus pardalis]) were collected in Misiones, Argentina, using a detection dog. Of the 289 feces collected, 209 (72.3%) had sufficient sample remaining to be used in this study and the majority of these were genetically confirmed to individual (81.3%) and sex (78.4%) level. In fact, these samples represent a minimum of 115 individuals (10 jaguars, 13 pumas, 33 ocelots, 38 oncillas, and 21 bush dogs). Through polymerase chain reaction, a 583-bp fragment in the VP2 gene of CPV was amplified in these samples. While no samples showed evidence of infection, this does not exclude the occurrence of CPV in wild carnivores in the area, as intermittent viral shedding could condition the diagnosis of CPV in feces of infected wild mammals. Locally, it is recommended that long-term monitoring of parvovirus be continued in wildlife and expanded to domestic carnivores. Internationally, this study provides a useful contribution to the approach to the sylvatic cycle of parvovirus in wild carnivores.