Epidemiology and genetic characteristics of murine kobuvirus from faecal samples of Rattus losea, Rattus tanezumi and Rattus norvegicus in southern China

Identification of Aichivirus in a Pet Rat (Rattus norvegicus) in Italy

We investigated the occurrence of eight potential zoonotic viruses in 91 exotic companion mammals from pet shops in southern Italy via real-time PCR and end-point PCR. The animals were screened for aichivirus, sapovirus, astrovirus, hepatitis A, noroviruses (GI and GII), rotavirus, circovirus, and SARS-CoV-2. Among the nine species of exotic pets studied, only one rat tested positive for aichivirus. The high sequence similarity to a murine kobuvirus-1 strain previously identified in China suggests that the virus may have been introduced into Italy through the importation of animals from Asia. Since exotic companion mammals live in close contact with humans, continuous sanitary monitoring is crucial to prevent the spread of new pathogens among domestic animals and humans. Further investigations on detecting and typing zoonotic viruses are needed to identify emerging and re-emerging viruses to safeguard public health.

A One-Year Retrospective Analysis of Viral and Parasitological Agents in Wildlife Animals Admitted to a First Aid Hospital

This study aimed to provide information on the presence and frequency of viral and parasitic agents in wildlife presented to a Veterinary Teaching Hospital in 2020-2021. Serum and faecal samples were collected from 50 rescued animals (roe deer, fallow deer, foxes, badgers, pine martens, and porcupines) and examined by serological, molecular, and parasitological techniques. Transtracheal wash (TTW) was also collected post-mortem from roe deer. Overall, the results of the different techniques showed infections with the following viral and parasitic agents: Bovine Viral Diarrhea Virus, Small Ruminant Lentiviruses, Kobuvirus, Astrovirus, Canine Adenovirus 1, Bopivirus, gastrointestinal strongyles, Capillaria, Ancylostomatidae, Toxocara canis, Trichuris vulpis, Hymenolepis, Strongyloides, Eimeria, Isospora, Dictyocaulus, Angiostrongylus vasorum, Crenosoma, Dirofilaria immitis, Neospora caninum, Giardia duodenalis, and Cryptosporidium. Sequencing (Tpi locus) identified G. duodenalis sub-assemblages AI and BIV in one roe deer and one porcupine, respectively. Adult lungworms collected from the TTW were identified as Dictyocaulus capreolus (COX1 gene). This is the first molecular identification of G. duodenalis sub-assemblage AI and D. capreolus in roe deer in Italy. These results show a wide presence of pathogens in wild populations and provide an overview of environmental health surveillance.

Highly Multiplexed Serology for Nonhuman Mammals

Emerging infectious diseases represent a serious and ongoing threat to humans. Most emerging viruses are maintained in stable relationships with other species of animals, and their emergence within the human population results from cross-species transmission. Therefore, if we want to be prepared for the next emerging virus, we need to broadly characterize the diversity and ecology of viruses currently infecting other animals (i.e., the animal virosphere). High-throughput metagenomic sequencing has accelerated the pace of virus discovery. However, molecular assays can detect only active infections and only if virus is present within the sampled fluid or tissue at the time of collection. In contrast, serological assays measure long-lived antibody responses to infections, which can be detected within the blood, regardless of the infected tissues. Therefore, serological assays can provide a complementary approach for understanding the circulation of viruses, and while serological assays have historically been limited in scope, recent advancements allow thousands to hundreds of thousands of antigens to be assessed simultaneously using <1 μL of blood (i.e., highly multiplexed serology). The application of highly multiplexed serology for the characterization of the animal virosphere is dependent on the availability of reagents that can be used to capture or label antibodies of interest. Here, we evaluate the utility of commercial immunoglobulin-binding proteins (protein A and protein G) to enable highly multiplexed serology in 25 species of nonhuman mammals, and we describe a competitive fluorescence-linked immunosorbent assay (FLISA) that can be used as an initial screen for choosing the most appropriate capture protein for a given host species. IMPORTANCE Antibodies are generated in response to infections with viruses and other pathogens, and they help protect against future exposures. Mature antibodies are long lived, are highly specific, and can bind to their protein targets with high affinity. Thus, antibodies can also provide information about an individual's history of viral exposures, which has important applications for understanding the epidemiology and etiology of disease. In recent years, there have been large advances in the available methods for broadly characterizing antibody-binding profiles, but thus far, these have been utilized primarily with human samples only. Here, we demonstrate that commercial antibody-binding reagents can facilitate modern antibody assays for a wide variety of mammalian species, and we describe an inexpensive and fast approach for choosing the best reagent for each animal species. By studying antibody-binding profiles in captive and wild animals, we can better understand the distribution and prevalence of viruses that could spill over into humans.

Epidemiological Evidence for Fecal-Oral Transmission of Murine Kobuvirus

Background

Murine Kobuvirus (MuKV) is a novel picornavirus of the genus Kobuvirus, and was first identified in the feces of murine rodents in the USA in 2011. There is limited information on the transmission route of MuKV. Thus, we conducted a study to investigate virus detection rates in fecal, serum, throat, and lung tissue samples from murine rodents.

Results

A total of 413 fecal samples, 385 lung samples, 269 throat swab samples, and 183 serum samples were collected from 413 murine rodents (Rattus norvegicus, Rattus tanezumi, and Rattus rattus) captured in urban Shenzhen. Kobuviruses were detected via RT-PCR. Only fecal samples were positive, with prevalence rates of 34.9% in Rattus norvegicus and 29.4% in Rattus tanezumi. Phylogenetic analysis based on partial 3D and complete VP1 sequence regions indicated that all of the MuKV sequences obtained belonged to Aichivirus A, and were genetically closely related to other MuKVs reported in China, Hungary, and the USA. Twenty-eight full-length MuKV sequences were acquired. Phylogenetic analysis of two sequences randomly selected from the two species (SZ59 and SZ171) indicated that they shared very high nucleotide and amino acid identity with one another (94.0 and 99.3%, respectively), and comparison with human Kobuvirus revealed amino acid identity values of ~80%. Additionally, a sewage-derived sequence shared high similarity with the rat-derived sequences identified in this study, with respective nucleotide and amino acid identity values from 86.5 and 90.7% to 87.2 and 91.1%.

Conclusion

The results of the current study provide evidence that murine Kobuvirus is transmitted via the fecal-oral route.

Using Environmental Sampling to Enable Zoonotic Pandemic Preparedness

The current pandemic caused by the SARS CoV-2, tracing back its origin possibly to a coronavirus associated with bats, has ignited renewed interest in understanding zoonotic spillovers across the globe. While research is more directed towards solving the problem at hand by finding therapeutic strategies and novel vaccine techniques, it is important to address the environmental drivers of pathogen spillover and the complex biotic and abiotic drivers of zoonoses. The availability of cutting-edge genomic technologies has contributed enormously to preempt viral emergence from wildlife. However, there is still a dearth of studies from species-rich South Asian countries, especially from India. In this review, we outline the importance of studying disease dynamics through environmental sampling from wildlife in India and how ecological parameters of both the virus and the host community may play a role in mediating cross-species spillovers. Non-invasive sampling using feces, urine, shed hair, saliva, shed skin, and feathers has been instrumental in providing genetic information for both the host and their associated pathogens. Here, we discuss the advances made in environmental sampling protocols and strategies to generate genetic data from such samples towards the surveillance and characterization of potentially zoonotic pathogens. We primarily focus on bat-borne or small mammal-borne zoonoses and propose a conceptual framework for non-invasive strategies to tackle the threat of emerging zoonotic infections.