Global Transmission, Spatial Segregation, and Recombination Determine the Long-Term Evolution and Epidemiology of Bovine Coronaviruses

Isolation and molecular characterization of an enteric isolate of the genotype-Ia bovine coronavirus with notable mutations in the receptor binding domain of the spike glycoprotein

BCoV new isolate was plaque purified, isolated, and propagated in vitro using MDBK and HRT-18. The full-length genome sequencing of this new BCoV isolate (31 Kbs) was drafted and deported in the GenBank. The genome organization is (5'-UTR-Gene-1-32kDa-HE-S-4.9 kDa-4.8 kDa-12.7 kDa-E-M-N-UTR-3'). Phylogenetic analysis based on the sequences of (the full-length genome, S, HE, and N) showed that the BCoV-13 clustered with other North American BCoV genotype I members. The sequence analysis shows several synonymous mutations among various domains of the S glycoprotein, especially the receptor binding domain. We found nine notable nucleotide deletions immediately downstream of the RNA binding domain of the nucleocapsid gene. Further gene function studies are encouraged to study the function of these mutations on the BCoV molecular pathogenesis and immune regulation. This research enhances our understanding of BCoV genomics and contributes to improved diagnostic and control measures for BCoV infections in cattle.

Genome-Wide Genomic Analysis and Evolutionary Insights into Bovine Coronavirus Strains in Southwest China

The global epidemic of bovine coronavirus (BCoV) has caused enormous economic losses. The characterisation and genetic composition of endemic strains in Southwest China remain elusive. This study aimed to fill this gap by isolating three BCoV strains from this region and sequencing their whole genomes. To elucidate the genetic evolution and characterisation of the prevalent strains, the results of BCoV sequences were compared in GenBank, with a focus on genetic evolution, mutation, and recombination patterns. The results showed close homology between strains NN190313 and NN230328, while strain NN221214 showed less similarity to these two strains but clustered with the French strain of the European branch. Intriguingly, NN190313 and NN230328 were grouped with goat-derived BCoV strains from Jiangsu Province in Eastern China in the Asian-American branch. In addition, recombination analyses revealed significant signals between NN230328 and either a Chinese goat-derived strain (XJCJ2301G) or a Shandong strain (ShX310). This study highlights the importance of monitoring cross-species transmission between cattle and goats, especially in the mountainous areas of Southwest China where mixed farming occurs, and thus, the monitoring of cross-species transmission between cattle and goats is important for preventing new public health challenges, providing important insights for research on cross-species transmission, early prevention, and control measures, with potential applications in vaccine development.

The forecasting power of the mucin-microbiome interplay in livestock respiratory diseases

Complex respiratory diseases are a significant challenge for the livestock industry worldwide. These diseases considerably impact animal health and welfare and cause severe economic losses. One of the first lines of pathogen defense combines the respiratory tract mucus, a highly viscous material primarily composed of mucins, and a thriving multi-kingdom microbial ecosystem. The microbiome-mucin interplay protects from unwanted substances and organisms, but its dysfunction may enable pathogenic infections and the onset of respiratory disease. Emerging evidence also shows that noncoding regulatory RNAs might modulate the structure and function of the microbiome-mucin relationship. This opinion paper unearths the current understanding of the triangular relationship between mucins, the microbiome, and noncoding RNAs in the context of respiratory infections in animals of veterinary interest. There is a need to look at these molecular underpinnings that dictate distinct health and disease outcomes to implement effective prevention, surveillance, and timely intervention strategies tailored to the different epidemiological contexts.

Advances in Laboratory Diagnosis of Coronavirus Infections in Cattle

Coronaviruses cause infections in humans and diverse species of animals and birds with a global distribution. Bovine coronavirus (BCoV) produces predominantly two forms of disease in cattle: a respiratory form and a gastrointestinal form. All age groups of cattle are affected by the respiratory form of coronavirus, whereas the gastroenteric form causes neonatal diarrhea or calf scours in young cattle and winter dysentery in adult cattle. The tremendous impacts of bovine respiratory disease and the associated losses are well-documented and underscore the importance of this pathogen. Beyond this, studies have demonstrated significant impacts on milk production associated with outbreaks of winter dysentery, with up to a 30% decrease in milk yield. In North America, BCoV was identified for the first time in 1972, and it continues to be a significant economic concern for the cattle industry. A number of conventional and molecular diagnostic assays are available for the detection of BCoV from clinical samples. Conventional assays for BCoV detection include virus isolation, which is challenging from clinical samples, electron microscopy, fluorescent antibody assays, and various immunoassays. Molecular tests are mainly based on nucleic acid detection and predominantly include conventional and real-time polymerase chain reaction (PCR) assays. Isothermal amplification assays and genome sequencing have gained increased interest in recent years for the detection, characterization, and identification of BCoV. It is believed that isothermal amplification assays, such as loop-mediated isothermal amplification and recombinase polymerase amplification, among others, could aid the development of barn-side point-of-care tests for BCoV. The present study reviewed the literature on coronavirus infections in cattle from the last three and a half decades and presents information mainly on the current and advancing diagnostics in addition to epidemiology, clinical presentations, and the impact of the disease on the cattle industry.

The Potential Roles of Host Cell miRNAs in Fine-Tuning Bovine Coronavirus (BCoV) Molecular Pathogenesis, Tissue Tropism, and Immune Regulation

Bovine coronavirus (BCoV) infection causes significant economic loss to the dairy and beef industries worldwide. BCoV exhibits dual tropism, infecting the respiratory and enteric tracts of cattle. The enteric BCoV isolates could also induce respiratory manifestations under certain circumstances. However, the mechanism of this dual tropism of BCoV infection has not yet been studied well. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and play a dual role in virus infection, mediating virus or modulating host immune regulatory genes through complex virus-host cell interactions. However, their role in BCoV infection remains unclear. This study aims to identify bovine miRNAs crucial for regulating virus-host interaction, influencing tissue tropism, and explore their potential as biomarkers and therapeutic agents against BCoV. We downloaded 18 full-length BCoV genomes (10 enteric and eight respiratory) from GenBank. We applied several bioinformatic tools to study the host miRNAs targeting various regions in the viral genome. We used the criteria of differential targeting between the enteric/respiratory isolates to identify some critical miRNAs as biological markers for BCoV infection. Using various online bioinformatic tools, we also searched for host miRNA target genes involved in BCoV infection, immune evasion, and regulation. Our results show that four bovine miRNAs (miR-2375, miR-193a-3p, miR-12059, and miR-494) potentially target the BCoV spike protein at multiple sites. These miRNAs also regulate the host immune suppressor pathways, which negatively impacts BCoV replication. Furthermore, we found that bta-(miR-2338, miR-6535, miR-2392, and miR-12054) also target the BCoV genome at certain regions but are involved in regulating host immune signal transduction pathways, i.e., type I interferon (IFN) and retinoic acid-inducible gene I (RIG-I) pathways. Moreover, both miR-2338 and miR-2392 also target host transcriptional factors RORA, YY1, and HLF, which are potential diagnostic markers for BCoV infection. Therefore, miR-2338, miR-6535, miR-2392, and miR-12054 have the potential to fine-tune BCoV tropism and immune evasion and enhance viral pathogenesis. Our results indicate that host miRNAs play essential roles in the BCoV tissue tropism, pathogenesis, and immune regulation. Four bovine miRNAs (miR-2375, bta-miR-193a-3p, bta-miR-12059, and bta-miR-494) target BCoV-S glycoprotein and are potentially involved in several immune suppression pathways during the viral infection. These miRNA candidates could serve as good genetic markers for BCoV infection. However, further studies are urgently needed to validate these identified miRNAs and their target genes in the context of BCoV infection and dual tropism and as genetic markers.

Identification of Astrovirus in the virome of the upper and lower respiratory tracts of calves with acute signs of bronchopneumonia

IMPORTANCE

Astroviruses (AstV) are known suspects of enteric disease in humans and livestock. Recently, AstV have been linked to encephalitis in immunocompromised patients and other animals, such as cattle, minks, and swine. In our study, we also identified AstV in the respiratory samples of calves with signs of bronchopneumonia, suggesting that their tropism could be even broader. We obtained one bovine AstV (BAstV) complete genome sequence by next-generation sequencing and showed that respiratory and enteric AstV from different species formed a divergent genetic cluster with AstV isolated from encephalitis cases, indicating that tropism might be strain-specific. These data provide further insight into understanding the biology of these understudied pathogens and suggest BAstV as a potential new candidate for bovine respiratory disease.

Molecular and genetic characterization of bovine parainfluenza type 3 European field and vaccine strains

Bovine Parainfluenza Type 3 virus (BPIV-3) is an enveloped, non-segmented single-stranded, negative-sense RNA virus belonging to the Paramyxoviridae family (genus Respirovirus) with a well-known role in Bovine Respiratory Disease (BRD) onset. Being isolated for the first time in 1959, BPIV-3 currently circulates worldwide in cattle herds and is routinely tested in suspected BRD cases. Different commercial vaccines are available to prevent infection and/or to reduce the clinical signs associated with BPIV-3 infection, which are essential to prevent secondary infections. Despite years of molecular surveillance, a very limited number of complete genome sequences were made publicly available, preventing thus the understanding of the genetic diversity of the circulating strains in the field. In addition, no data about the genetic identity between field and vaccine strains is currently available. In this study, we sequenced the full-genome and genetically characterized BPIV-3 strains isolated from animals displaying respiratory illness in France and Sweden, as well as the vaccine strains contained in three different commercialized vaccines. Our results show that the sequences from France and Sweden belong to genotype C. However, a third sequence from Sweden from 2017 clustered within genotype A. The sequencing of vaccine strains revealed that two of the vaccine strains clustered within genotype C, whereas the third vaccine strain belonged to genotype A. Altogether, our findings suggest that both genotypes A and C circulate in Europe and that BPIV-3 field and vaccine strains are genetically divergent. Our sequencing results could be useful to better understand the genetic differences between the circulating field and vaccine BPIV-3 strains. This is crucial for a correct interpretation of diagnostic findings and for the assessment of BPIV-3 prevalence in cattle population.

Prevalence of bovine coronavirus in cattle in China: A systematic review and meta-analysis

Bovine coronavirus (BCoV) is one of the important pathogens that cause calf diarrhea (CD), winter dysentery (WD), and the bovine respiratory disease complex (BRDC), and spreads worldwide. An infection of BCoV in cattle can lead to death of young animals, stunted growth, reduced milk production, and milk quality, thus bringing serious economic losses to the bovine industry. Therefore, it is necessary to prevent and control the spread of BCoV. Here, a systematic review and meta-analysis was conducted to assess the prevalence of BCoV in cattle in China before 2022. A total of 57 articles regarding the prevalence of BCoV in cattle in China were collected from five databases (PubMed, ScienceDirect, CNKI, VIP, and Wan Fang). Based on the inclusion criteria, a total of 15,838 samples were included, and 6,136 were positive cases. The overall prevalence of BCoV was 30.8%, with the highest prevalence rate (60.5%) identified in South China and the lowest prevalence (15.6%) identified in Central China. We also analyzed other subgroup information, included sampling years, sample sources, detection methods, breeding methods, age, type of cattle, presence of diarrhea, and geographic and climatic factors. The results indicated that BCoV was widely prevalent in China. Among all subgroups, the sample sources, detection methods, breeding methods, and presence or absence of diarrheal might be potential risk factors responsible for BCoV prevalence. It is recommended to strengthen the detection of BCoV in cattle, in order to effectively control the spread of BCoV.

[Genetic diversity of Siberian bovine coronavirus isolates (Coronaviridae: Coronavirinae: Betacoronavirus-1: Bovine-Like coronaviruses)]

INTRODUCTION

Bovine coronaviruses (BCoVs) are causative agents of diarrhea, respiratory diseases in calves and winter cow dysentery. The study of genetic diversity of these viruses is topical issue. The purpose of the research is studying the genetic diversity of BCoV isolates circulating among dairy cattle in Siberia.

MATERIALS AND METHODS

Specimens used in this study were collected from animals that died or was forcedly slaughtered before the start of the study. The target for amplification were nucleotide sequences of S and N gene regions.

RESULTS

Based on the results of RT-PCR testing, virus genome was present in 16.3% of samples from calves with diarrheal syndrome and in 9.9% with respiratory syndrome. The nucleotide sequences of S gene region were determined for 18 isolates, and N gene sequences - for 12 isolates. Based on S gene, isolates were divided into two clades each containing two subclades. First subclade of first clade (European line) included 11 isolates. Second one included classic strains Quebec and Mebus, strains from Europe, USA and Korea, but none of sequences from this study belonged to this subclade. 6 isolates belonged to first subclade of second clade (American-Asian line). Second subclade (mixed line) included one isolate. N gene sequences formed two clades, one of them included two subclades. First subclade included 3 isolates (American-Asian line), and second subclade (mixed) included one isolate. Second clade (mixed) included 8 sequences. No differences in phylogenetic grouping between intestinal and respiratory isolates, as well as according to their geographic origin were identified.

CONCLUSION

The studied population of BCoV isolates is heterogeneous. Nucleotide sequence analysis is a useful tool for studying molecular epidemiology of BCoV. It can be beneficial for choice of vaccines to be used in a particular geographic region.

Occurrence of Bovine Coronavirus and other Major Respiratory Viruses in Cattle in Poland

Introduction

Bovine coronavirus (BCoV) is a causative agent of enteric and respiratory diseases in cattle. Despite its importance for animal health, no data is available on its prevalence in Poland. The aim of the study was to determine the virus' seroprevalence, identify risk factors of BCoV exposure in selected cattle farms and investigate the genetic variability of circulating strains.

Material and Methods

Serum and nasal swab samples were collected from 296 individuals from 51 cattle herds. Serum samples were tested with ELISA for the presence of BCoV-, bovine herpesvirus-1 (BoHV-1)- and bovine viral diarrhoea virus (BVDV)-specific antibodies. The presence of those viruses in nasal swabs was tested by real-time PCR assays. Phylogenetic analysis was performed using fragments of the BCoV S gene.

Results

Antibodies specific to BCoV were found in 215 (72.6%) animals. Seropositivity for BCoV was more frequent (P>0.05) in calves under 6 months of age, animals with respiratory signs coinfected with BoHV-1 and BVDV and increased with herd size. In the final model, age and herd size were established as risk factors for BCoV-seropositivity. Genetic material of BCoV was found in 31 (10.5%) animals. The probability of BCoV detection was the highest in medium-sized herds. Polish BCoVs showed high genetic homology (98.3-100%) and close relatedness to European strains.

Conclusion

Infections with BCoV were more common than infections with BoHV-1 and BVDV. Bovine coronavirus exposure and shedding show age- and herd density-dependence.

Understanding the mechanisms of viral and bacterial coinfections in bovine respiratory disease: a comprehensive literature review of experimental evidence

Bovine respiratory disease (BRD) is one of the most important diseases impacting the global cattle industry, resulting in significant economic loss. Commonly referred to as shipping fever, BRD is especially concerning for young calves during transport when they are most susceptible to developing disease. Despite years of extensive study, managing BRD remains challenging as its aetiology involves complex interactions between pathogens, environmental and host factors. While at the beginning of the twentieth century, scientists believed that BRD was only caused by bacterial infections ("bovine pasteurellosis"), we now know that viruses play a key role in BRD induction. Mixtures of pathogenic bacteria and viruses are frequently isolated from respiratory secretions of animals with respiratory illness. The increased diagnostic screening data has changed our understanding of pathogens contributing to BRD development. In this review, we aim to comprehensively examine experimental evidence from all existing studies performed to understand coinfections between respiratory pathogens in cattle. Despite the fact that pneumonia has not always been successfully reproduced by in vivo calf modelling, several studies attempted to investigate the clinical significance of interactions between different pathogens. The most studied model of pneumonia induction has been reproduced by a primary viral infection followed by a secondary bacterial superinfection, with strong evidence suggesting this could potentially be one of the most common scenarios during BRD onset. Different in vitro studies indicated that viral priming may increase bacterial adherence and colonization of the respiratory tract, suggesting a possible mechanism underpinning bronchopneumonia onset in cattle. In addition, a few in vivo studies on viral coinfections and bacterial coinfections demonstrated that a primary viral infection could also increase the pathogenicity of a secondary viral infection and, similarly, dual infections with two bacterial pathogens could increase the severity of BRD lesions. Therefore, different scenarios of pathogen dynamics could be hypothesized for BRD onset which are not limited to a primary viral infection followed by a secondary bacterial superinfection.

First report and genomic characterization of a bovine-like coronavirus causing enteric infection in an odd-toed non-ruminant species (Indonesian tapir, Acrocodia indica) during an outbreak of winter dysentery in a zoo

Bovine coronavirus (BCoV) is associated with three distinct clinical syndromes in cattle that is, neonatal diarrhoea, haemorrhagic diarrhoea in adults (the so-called winter dysentery syndrome, WD) and respiratory infections in cattle of different ages. In addition, bovine-like CoVs have been detected in various species including domestic and wild ruminants. However, bovine-like CoVs have not been reported so far in odd-toed ungulates. We describe an outbreak of WD associated with a bovine-like CoV affecting several captive wild ungulates, including Indonesian tapirs (Acrocodia indica) an odd-toed ungulate species (Perissodactyla) which, with even-toed ungulates species (Artiodactyla) form the clade Euungulata. Genomic characterization of the CoV revealed that it was closely related to BCoVs previously reported in America. This case illustrates the adaptability of bovine-like CoVs to new species and the necessity of continued surveillance of bovine-like CoVs in various species.

Advances in Bovine Coronavirus Epidemiology

Bovine coronavirus (BCoV) is a causative agent of enteric and respiratory disease in cattle. BCoV has also been reported to cause a variety of animal diseases and is closely related to human coronaviruses, which has attracted extensive attention from both cattle farmers and researchers. However, there are few comprehensive epidemiological reviews, and key information regarding the effect of S-gene differences on tissue tendency and potential cross-species transmission remain unclear. In this review, we summarize BCoV epidemiology, including the transmission, infection-associated factors, co-infection, pathogenicity, genetic evolution, and potential cross-species transmission. Furthermore, the potential two-receptor binding motif system for BCoV entry and the association between BCoV and SARS-CoV-2 are also discussed in this review. Our aim is to provide valuable information for the prevention and treatment of BCoV infection throughout the world.

Bovine Coronavirus Infects the Respiratory Tract of Cattle Challenged Intranasally

Bovine Coronavirus (BCoV) is a member of a family of viruses associated with both enteric and respiratory diseases in a wide range of hosts. BCoV has been well-established as a causative agent of diarrhea in cattle, however, its role as a respiratory pathogen is controversial. In this study, fifteen calves were challenged intranasally with virulent BCoV in order to observe the clinical manifestation of the BCoV infection for up to 8 days after initial challenge, looking specifically for indication of symptoms, pathology, and presence of viral infection in the respiratory tract, as compared to six unchallenged control calves. Throughout the study, clinical signs of disease were recorded and nasal swabs were collected daily. Additionally, bronchoalveolar lavage (BAL) was performed at 4 days Post-challenge, and blood and tissue samples were collected from calves at 4, 6, or 8 days Post-challenge to be tested for the presence of BCoV and disease pathology. The data collected support that this BCoV challenge resulted in respiratory infections as evidenced by the isolation of BCoV in BAL fluids and positive qPCR, immunohistochemistry (IHC), and histopathologic lesions in the upper and lower respiratory tissues. This study can thus be added to a growing body of data supporting that BCoV is a respiratory pathogen and contributor to respiratory disease in cattle.

Development and assessment of a new bioassay for accurate quantification of Type I interferons induced by bovine respiratory viruses

Type I interferon (IFN-I) plays a major role in antiviral and inflammatory processes of the infected host. In the bovine industry, the bovine respiratory disease complex is a major cause of economic and health problems. This disease is caused by interactions of pathogens, together with environmental and host factors. Several pathogens have been identified as causal agents of respiratory diseases in cattle. To better understand how primary infections by viruses predispose animals to further infections by pathogenic bacteria, tools to accurately detect antiviral and immunoregulatory cytokines are needed. To facilitate the detection and quantification of bovine IFN-I, we have established a new specific and sensitive bioassay studies in the bovine host. This assay is based on a Madin-Darby Bovine Kidney (MDBK) cell line that carries a luciferase gene under the control of the IFN-I inducible bovine Mx1 promoter. Specific luciferase activity was measured after stimulation with serial dilutions of recombinant bovine alpha and beta IFNs and human IFN-α. With this novel bioassay we have successfully measured IFN-I production in supernatant from MDBK cells after stimulation of Toll-like receptors (TLR3, TLR7 and TLR8) and RIG-I-like receptors (RIG-I and MDA5), after viral infection with bovine respiratory pathogens, but also in samples from infected calves. Finally, this new bioassay is an easy-to-use and low cost tool to measure the production of bovine Type-I Interferon.

Epidemiological survey and genetic diversity of bovine coronavirus in Northeast China

In 2020, to trace the prevalence and evolution of bovine coronavirus (BCoV) in China, a total of 1383 samples (1016 fecal samples and 367 nasal swab samples) were collected from 1016 cattle exhibiting diarrhea symptoms on dairy farms and beef cattle farms in Heilongjiang Province, Northeast China. All samples were subjected to reverse transcription-polymerase chain reaction (RT-PCR) detection of the BCoV N gene, followed by an analysis of its epidemiology and genetic evolution. The results indicated that of the 1016 diarrhea-affected cattle, 15.45% (157/1016) were positive for BCoV, in which positive rates of the fecal and nasal swab samples were 12.20% (124/1016) and 21.53% (79/367), respectively. Of the 367 cattle whose nasal swab samples were collected, the BCoV positive rate of the corresponding fecal samples was 15.26% (56/367). BCoV infection was significantly associated with age, farming pattern, cattle type, farm latitude, sample type, and clinical symptom (p < 0.05). Of the 203 BCoV-positive samples, 20 spike (S) genes were successfully sequenced. The 20 identified BCoV strains shared nucleotide homologies of 97.7-100.0%, and their N-terminal domain of S1 subunit (S1-NTD: residues 15-298) differed genetically from the reference strains of South Korea and Europe. The 20 identified BCoV strains were clustered in the Asia-North America group (GII group) in the global strain-based phylogenetic tree and formed three clades in the Chinese strain-based phylogenetic tree. The HLJ/HH-10/2020 strain was clustered into the Europe group (GI group) in the S1-NTD-based phylogenetic tree, exhibiting N¹⁴⁶/I, D¹⁴⁸/G, and L¹⁵⁴/F mutations that affect the S protein structure. Of the identified BCoV strains, one potential recombination event occurred between the HLJ/HH-20/2020 and HLJ/HH-10/2020 strains, which led to the generation of the recombinant BCV-AKS-01 strain. A selective pressure analysis on the S protein revealed one positively selected site (Asn⁵⁰⁹) among the 20 identified BCoV strains located inside the putative receptor binding domain (residues 326-540). These data provide a greater understanding of the epidemiology and evolution of BCoV in China.

Characterization of Winter Dysentery Bovine Coronavirus Isolated from Cattle in Israel

Bovine coronavirus (BCoV) is the causative agent of winter dysentery (WD). In adult dairy cattle, WD is characterized by hemorrhagic diarrhea and a reduction in milk production. Therefore, WD leads to significant economic losses in dairy farms. In this study, we aimed to isolate and characterize local BCoV strains. BCoV positive samples, collected during 2017–2021, were used to amplify and sequence the S1 domain of S glycoprotein and the full hemagglutinin esterase gene. Based on our molecular analysis, local strains belong to different genetic variants circulating in dairy farms in Israel. Phylogenetic analysis revealed that all local strains clustered together and in proximity to other BCoV circulating in the area. Additionally, we found that local strains are genetically distant from the reference enteric strain Mebus. To our knowledge, this is the first report providing molecular data on BCoV circulating in Israel.

Animal Coronaviruses and SARS-COV-2 in Animals, What Do We Actually Know?

Coronaviruses (CoVs) are a well-known group of viruses in veterinary medicine. We currently know four genera of Coronavirus, alfa, beta, gamma, and delta. Wild, farmed, and pet animals are infected with CoVs belonging to all four genera. Seven human respiratory coronaviruses have still been identified, four of which cause upper-respiratory-tract diseases, specifically, the common cold, and the last three that have emerged cause severe acute respiratory syndromes, SARS-CoV-1, MERS-CoV, and SARS-CoV-2. In this review we briefly describe animal coronaviruses and what we actually know about SARS-CoV-2 infection in farm and domestic animals.

Review a brief history of coronaviruses in Thailand

As with many countries around the world, Thailand is currently experiencing restrictions to daily life as a consequence of the worldwide transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is the third respiratory syndrome coronavirus to be introduced into Thailand, following previous importation of cases of the severe acute respiratory syndrome coronavirus (SARS) and the Middle East respiratory syndrome coronavirus (MERS). Unlike SARS and MERS, SARS-CoV-2 was able to establish local transmission in Thailand. In addition to the imported coronaviruses, Thailand has a number of endemic coronaviruses that can affect livestock and pet species, can be found in bats, as well as four human coronaviruses that are mostly associated with the common cold. This article seeks to review what is known on both the endemic and imported coronaviruses in Thailand.

Fatal Interstitial Pneumonia Associated with Bovine Coronavirus in Cows from Southern Italy

An outbreak of winter dysentery, complicated by severe respiratory syndrome, occurred in January 2020 in a high production dairy cow herd located in a hilly area of the Calabria region. Of the 52 animals belonging to the farm, 5 (9.6%) died with severe respiratory distress, death occurring 3–4 days after the appearance of the respiratory signs (caught and gasping breath). Microbiological analysis revealed absence of pathogenic bacteria whilst Real-time PCR identified the presence of RNA from Bovine Coronavirus (BCoV) in several organs: lungs, small intestine (jejunum), mediastinal lymph nodes, liver and placenta. BCoV was therefore hypothesized to play a role in the lethal pulmonary infection. Like the other CoVs, BCoV is able to cause different syndromes. Its role in calf diarrhea and in mild respiratory disease is well known: we report instead the involvement of this virus in a severe and fatal respiratory disorder, with symptoms and disease evolution resembling those of Severe Acute Respiratory Syndromes (SARS).

Bovine Coronavirus: Variability, Evolution, and Dispersal Patterns of a No Longer Neglected Betacoronavirus

Bovine coronavirus (BoCV) is an important pathogen of cattle, causing severe enteric disease and playing a role in the bovine respiratory disease complex. Similar to other coronaviruses, a remarkable variability characterizes both its genome and biology. Despite their potential relevance, different aspects of the evolution of BoCV remain elusive. The present study reconstructs the history and evolution of BoCV using a phylodynamic approach based on complete genome and spike protein sequences. The results demonstrate high mutation and recombination rates affecting different parts of the viral genome. In the spike gene, this variability undergoes significant selective pressures—particularly episodic pressure—located mainly on the protein surface, suggesting an immune-induced selective pressure. The occurrence of compensatory mutations was also identified. On the contrary, no strong evidence in favor of host and/or tissue tropism affecting viral evolution has been proven. The well-known plasticity is thus ascribable to the innate broad viral tropism rather than mid- or long-term adaptation. The evaluation of the geographic spreading pattern clearly evidenced two clusters: a European cluster and an American–Asian cluster. While a relatively dense and quick migration network was identified in the former, the latter was dominated by the primary role of the United States (US) as a viral exportation source. Since the viral spreading pattern strongly mirrored the cattle trade, the need for more intense monitoring and preventive measures cannot be underestimated as well as the need to enforce the vaccination of young animals before international trade, to reduce not only the clinical impact but also the transferal and mixing of BoCV strains.

Animal Coronaviruses in the Light of COVID-19

Coronaviruses are extremely susceptible to genetic changes due to the characteristic features of the genome structure, life cycle and environmental pressure. Their remarkable variability means that they can infect many different species of animals and cause different disease symptoms. Moreover, in some situations, coronaviruses might be transmitted across species. Although they are commonly found in farm, companion and wild animals, causing clinical and sometimes serious signs resulting in significant economic losses, not all of them have been classified by the World Organization for Animal Health (OIE) as hazardous and included on the list of notifiable diseases. Currently, only three diseases caused by coronaviruses are on the OIE list of notifiable terrestrial and aquatic animal diseases. However, none of these three entails any administrative measures. The emergence of the SARS-CoV-2 infections that have caused the COVID-19 pandemic in humans has proved that the occurrence and variability of coronaviruses is highly underestimated in the animal reservoir and reminded us of the critical importance of the One Health approach. Therefore, domestic and wild animals should be intensively monitored, both to broaden our knowledge of the viruses circulating among them and to understand the mechanisms of the emergence of viruses of relevance to animal and human health.