Evidence of canine parvovirus transmission to a civet cat (Paradoxurus musangus) in Singapore

Carcass appearance does not influence scavenger avoidance of carnivore carrion

The selection or avoidance of certain carrion resources by vertebrate scavengers can alter the flow of nutrients in ecosystems. Evidence suggests higher trophic level carrion is scavenged by fewer vertebrate species and persists longer when compared to lower trophic level carrion, although it is unclear how scavengers distinguish between carcasses of varying species. To investigate carnivore carrion avoidance and explore sensory recognition mechanisms in scavenging species, we investigated scavenger use of intact and altered (i.e., skin, head, and feet removed) coyote-Canis latrans (carnivore) and wild pig-Sus scrofa (omnivore) carcasses experimentally placed at the Savannah River Site, SC, USA. We predicted carnivore carcasses would persist longer due to conspecific and intraguild scavenger avoidance. Further, we hypothesized visually modifying carcasses would not reduce avoidance of carnivore carrion, given scavengers likely depend largely on chemical cues when assessing carrion resources. As expected, mammalian carnivores largely avoided scavenging on coyote carcasses, resulting in carnivore carcasses having longer depletion times than wild pig carcasses at intact and altered trials. Therefore, nutrients derived from carnivore carcasses are not as readily incorporated into higher trophic levels and scavengers largely depend on olfactory cues when assessing benefits and risks associated with varying carrion resources.

Fatal canine parvovirus type 2a and 2c infections in wild Chinese pangolins (Manis pentadactyla) in southern China

The Chinese pangolin (Manis pentadactyla) is a critically endangered scale-covered mammal belonging to the order Pholidota. Wild pangolins are notably susceptible to pathogen infection and are typically characterized by impoverished health. However, little is currently known regarding the viruses prevalent among pangolins. In this study, we report the detection of two subtypes of canine parvovirus type 2 (CPV-2), namely CPV-2a and CPV-2c, both of which caused severe diarrheal disease in two post-rescue pangolins with fatal consequences. As in CPV-2-infected dogs, intensive lesion of the mucosal layer of the small intestines is a prominent feature in infected pangolins. Moreover, the immunochemistry results demonstrated that CPV-2 antigens were distributed in the crypts of small intestine. Additionally, typical parvovirus-associated CPV-2 were detected after four passages in F81 cells, and typical parvovirus-like particles, approximately 20 nm in diameter, were observed in the cell supernatants. Phylogenetic analysis revealed that the VP2 viral protein sequences (GenBank accession number OP208805) isolated from one pangolin (termed P1) were classified as CPV-2c, with 99.8% identity to a CPV-2c strain (MN832850) isolated from a Taiwanese pangolin found in Taiwan Province. In contrast, VP2 sequences (#OP208806) obtained from the second pangolin (P2) were classified as CPV-2a, with 99.8% identity to a CPV-2a strain (KY386858) isolated from southern China. In this study, we thus confirmed the infection of pangolins with CPV-2c in mainland China and demonstrated that CPV-2a also can infect pangolins. Based on these findings, we recommend that further investigations should be conducted to establish the interspecies transmission of these viruses among wild pangolins, wild carnivores, and stray dogs.

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.

Probiotics at War Against Viruses: What Is Missing From the Picture?

Our world is now facing a multitude of novel infectious diseases. Bacterial infections are treated with antibiotics, albeit with increasing difficulty as many of the more common causes of infection have now developed broad spectrum antimicrobial resistance. However, there is now an even greater challenge from both old and new viruses capable of causing respiratory, enteric, and urogenital infections. Reports of viruses resistant to frontline therapeutic drugs are steadily increasing and there is an urgent need to develop novel antiviral agents. Although this all makes sense, it seems rather strange that relatively little attention has been given to the antiviral capabilities of probiotics. Over the years, beneficial strains of lactic acid bacteria (LAB) have been successfully used to treat gastrointestinal, oral, and vaginal infections, and some can also effect a reduction in serum cholesterol levels. Some probiotics prevent gastrointestinal dysbiosis and, by doing so, reduce the risk of developing secondary infections. Other probiotics exhibit anti-tumor and immunomodulating properties, and in some studies, antiviral activities have been reported for probiotic bacteria and/or their metabolites. Unfortunately, the mechanistic basis of the observed beneficial effects of probiotics in countering viral infections is sometimes unclear. Interestingly, in COVID-19 patients, a clear decrease has been observed in cell numbers of Lactobacillus and Bifidobacterium spp., both of which are common sources of intestinal probiotics. The present review, specifically motivated by the need to implement effective new counters to SARS-CoV-2, focusses attention on viruses capable of co-infecting humans and other animals and specifically explores the potential of probiotic bacteria and their metabolites to intervene with the process of virus infection. The goal is to help to provide a more informed background for the planning of future probiotic-based antiviral research.

Genetic characterization of Carnivore Parvoviruses in Spanish wildlife reveals domestic dog and cat-related sequences

The impact of carnivore parvovirus infection on wild populations is not yet understood; disease signs are mainly developed in pups and assessing the health of litters in wild carnivores has big limitations. This study aims to shed light on the virus dynamics among wild carnivores thanks to the analysis of 213 samples collected between 1994 and 2013 in wild ecosystems from Spain. We determined the presence of carnivore parvovirus DNA by real-time PCR and sequenced the vp2 gen from 22 positive samples to characterize the strains and to perform phylogenetic analysis. The presence of carnivore parvovirus DNA was confirmed in 18% of the samples, with a higher prevalence detected in wolves (Canis lupus signatus, 70%). Fourteen sequences belonging to nine wolves, three Eurasian badgers (Meles meles), a common genet (Genetta genetta) and a European wildcat (Felis silvestris) were classified as canine parvovirus 2c (CPV-2c); five sequences from three wolves, a red fox (Vulpes vulpes) and a stone marten (Martes foina) as CPV-2b; and three sequences from a badger, a genet and a stone marten as feline parvovirus (FPV). This was the first report of a wildcat infected with a canine strain. Sequences described in this study were identical or very close related to others previously found in domestic carnivores from distant countries, suggesting that cross-species transmission takes place and that the parvovirus epidemiology in Spain, as elsewhere, could be influenced by global factors.

First characterization of a canine parvovirus causing fatal disease in coatis (Nasua nasua)

A canine parvovirus (CPV)-like virus was detected by PCR and isolated from dead coatis in Argentina. Analysis of the full-length genome sequence revealed that it resembled CPV-but also contained a mutation in the VP2 protein (Arg377Ser) that has not been described previously. This is the first report of a CPV-like virus producing clinical disease in coatis. Genetic similarity to CPV-2c viruses detected in Brazil suggests a strong relationship between these viruses. Although the pathogenic potential of CPV- and feline panleukopenia virus (FPV)-like strains in wild animals is still not completely understood, this study highlights the importance of parvoviruses as a threat to wildlife if proper conditions are present.

Detection and genetic characterization of diverse Bartonella genotypes in the small mammals of Singapore

Bartonella species are arthropod-borne bacterial pathogens that infect numerous mammalian species. Small mammals play an important role as natural reservoirs of many Bartonella species, maintaining the greatest diversity of Bartonella described to date. Although Bartonella research has been conducted in Southeast Asia, no studies have been undertaken on small mammals in Singapore. Here, we report the detection and description of Bartonella in small mammals in Singapore during the period of November 2011 to May 2014. BartonellaDNA was detected in 20.8% (22/106) of small mammal spleens with a PCR amplifying the beta subunit of bacterial RNA polymerase (rpoB) gene. Commensal species Rattus norvegicus and Rattus tanezumi had the highest prevalence, 75% (3/4) and 34,5% (10/29), followed by Suncus murinus 30% (6/20), Tupaia glis 16,7% (1/6) and Mus castaneus 13.3% (2/15). Phylogenetic analysis of 18 rpoB gene sequences revealed five Bartonella genotypes circulating in the small mammals of Singapore. Bayesian tip-significance testing demonstrated strong structuring in the geographical signal, indicating that distribution of Bartonella species is correlated to the distribution of their hosts. Major deforestation and fragmentation in Singapore favour synanthropic species that traverse habitats and increase the possibility of spillover to incidental hosts.

Influence of age and body condition on astrovirus infection of bats in Singapore: An evolutionary and epidemiological analysis

Bats are unique mammals that are reservoirs of high levels of virus diversity. Although several of these viruses are zoonotic, the majority are not. Astroviruses, transmitted fecal-orally, are commonly detected in a wide diversity of bat species, are prevalent at high rates and are not thought to directly infect humans. These features make astroviruses useful in examining virus evolutionary history, epidemiology in the host, and temporal shedding trends. Our study screened for the presence of astroviruses in bats in Singapore, reconstructed the phylogenetic relations of the polymerase genes and tested for population characteristics associated with infection. Of the seven species screened, astroviruses were detected in Rhinolophus lepidus and Eonycteris spelaea. The R. lepidus sequences grouped with other Rhinolophus astrovirus sequences from China and Laos, while the Eoncyteris sequences formed a distinct clade with astroviruses from Rousettus spp. in Laos and Pteropus giganteus in Bangladesh, but not with other E. spelaea sequences. Longitudinal collections of Eonycteris feces demonstrated variable shedding. Juvenile status of bats was a risk factor for astroviruses. This study highlights the diversity of astroviruses in nectivorous and insectivorous bats in Singapore and provides a predictive framework for understanding astrovirus infection in these bats. It also suggests that in addition to host phylogenetic relatedness, host ecology, such as roosting behavior, may drive co-infections, virus maintenance and spillover.