SARS-CoV-2 B.1.1.7 variant of concern detected in a pet dog and cat after exposure to a person with COVID-19, USA

COVID-19 scent dog research highlights and synthesis during the pandemic of December 2019-April 2023

CONTEXT

This review was undertaken to provide information concerning the advancement of research in the area of COVID-19 screening and testing during the worldwide pandemic from December 2019 through April 2023. In this review, we have examined the safety, effectiveness, and practicality of utilizing trained scent dogs in clinical and public situations for COVID-19 screening. Specifically, results of 29 trained scent dog screening peer-reviewed studies were compared with results of real-time reverse-transcription polymerase chain reaction (RT-PCR) and rapid antigen (RAG) COVID-19 testing methods.

OBJECTIVES

The review aims to systematically evaluate the strengths and weaknesses of utilizing trained scent dogs in COVID-19 screening.

METHODS

At the time of submission of our earlier review paper in August 2021, we found only four peer-reviewed COVID-19 scent dog papers: three clinical research studies and one preprint perspective paper. In March and April 2023, the first author conducted new literature searches of the MEDLINE/PubMed, Google Scholar, and Cochrane Library websites. Again, the keyword phrases utilized for the searches included "COVID detection dogs," "COVID scent dogs," and "COVID sniffer dogs." The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 Checklist was followed to ensure that our review adhered to evidence-based guidelines for reporting. Utilizing the results of the reviewed papers, we compiled statistics to intercompare and summarize basic information concerning the scent dogs and their training, the populations of the study participants, the types of sampling methods, the comparative tests utilized, and the effectiveness of the scent dog screening.

RESULTS

A total of 8,043 references were identified through our literature search. After removal of duplicates, there were 7,843 references that were screened. Of these, 100 were considered for full-text eligibility, 43 were included for qualitative synthesis, and 29 were utilized for quantitative analysis. The most relevant peer-reviewed COVID-19 scent dog references were identified and categorized. Utilizing all of the scent dog results provided for this review, we found that 92.3 % of the studies reached sensitivities exceeding 80 and 32.0 % of the studies exceeding specificities of 97 %. However, 84.0 % of the studies reported specificities above 90 %. Highlights demonstrating the effectiveness of the scent dogs include: (1) samples of breath, saliva, trachea-bronchial secretions and urine as well as face masks and articles of clothing can be utilized; (2) trained COVID-19 scent dogs can detect presymptomatic and asymptomatic patients; (3) scent dogs can detect new SARS-CoV-2 variants and Long COVID-19; and (4) scent dogs can differentiate SARS-CoV-2 infections from infections with other novel respiratory viruses.

CONCLUSIONS

The effectiveness of the trained scent dog method is comparable to or in some cases superior to the real-time RT-PCR test and the RAG test. Trained scent dogs can be effectively utilized to provide quick (seconds to minutes), nonintrusive, and accurate results in public settings and thus reduce the spread of the COVID-19 virus or other viruses. Finally, scent dog research as described in this paper can serve to increase the medical community's and public's knowledge and acceptance of medical scent dogs as major contributors to global efforts to fight diseases.

Genomic Characteristics of Feline Anelloviruses Isolated from Domestic Cats in Shanghai, China

Viral metagenomics techniques allow the high-throughput discovery of possible pathogens carried by companion animals from their feces and other excreta. In this study, the viral metagenomics of 22 groups of fecal samples from domestic cats revealed a high prevalence of feline anelloviruses (FcTTV) infection in domestic cats in Shanghai, China. Serum samples from 30 cat individuals were further detected by polymerase chain reaction, and an average positive rate of 36.67% (11/30) of FcTTV infection was found. Next, the full-length sequences of five Shanghai FcTTV variants were obtained and submitted to GenBank with access numbers OP186140 to OP186144. Phylogenetic analysis indicates that the Shanghai FcTTV variants have relatively consistent genomic characteristics, with two variants from Zhejiang 2019 and one variant from the Czech Republic 2010. The recombination event analysis of the variants showed that one variant (OP186141_SH-02) had a primary parental sequence derived from a variant (KM229764) from the Czech Republic in 2010, while the secondary parental sequence was derived from OP186140_SH-01. The results revealed that FcTTV infection is prevalent in domestic cats and that the use of viral metagenomics to rapidly identify some infecting viruses whose hosts lack clinical features would be an effective approach.

Neutralizing Antibodies against the SARS-CoV-2 Ancestral Strain and Omicron BA.1 Subvariant in Dogs and Cats in Mexico

SARS-CoV-2 mainly affects humans; however, it is important to monitor the infection of companion and wild animals as possible reservoirs of this virus. In this sense, seroprevalence studies in companion animals, such as dogs and cats, provide important information about the epidemiology of SARS-CoV-2. This study aimed to evaluate the seroprevalence of neutralizing antibodies (nAbs) against the ancestral strain and the Omicron BA.1 subvariant in dogs and cats in Mexico. Six hundred and two samples were obtained from dogs (n = 574) and cats (n = 28). These samples were collected from the end of 2020 to December 2021 from different regions of Mexico. The presence of nAbs was evaluated using a plaque reduction neutralization test (PRNT) and microneutralization (MN) assays. The results showed that 14.2% of cats and 1.5% of dogs presented nAbs against the ancestral strain of SARS-CoV-2. The analysis of nAbs against Omicron BA.1 in cats showed the same percentage of positive animals but a reduced titer. In dogs, 1.2% showed nAbs against Omicron BA.1. These results indicate that nAbs were more frequent in cats than in dogs and that these nAbs have a lower capacity to neutralize the subvariant Omicron BA.1.

A SARS-CoV-2: Companion Animal Transmission and Variants Classification

The continuous emergence of novel viruses and their diseases are a threat to global public health as there have been three outbreaks of coronaviruses that are highly pathogenic to humans in the span of the last two decades, severe acute respiratory syndrome (SARS)-CoV in 2002, Middle East respiratory syndrome (MERS)-CoV in 2012, and novel SARS-CoV-2 which emerged in 2019. The unprecedented spread of SARS-CoV-2 worldwide has given rise to multiple SARS-CoV-2 variants that have either altered transmissibility, infectivity, or immune escaping ability, causing diseases in a broad range of animals including human and non-human hosts such as companion, farm, zoo, or wild animals. In this review, we have discussed the recent SARS-CoV-2 outbreak, potential animal reservoirs, and natural infections in companion and farm animals, with a particular focus on SARS-CoV-2 variants. The expeditious development of COVID-19 vaccines and the advancements in antiviral therapeutics have contained the COVID-19 pandemic to some extent; however, extensive research and surveillance concerning viral epidemiology, animal transmission, variants, or seroprevalence in diverse hosts are essential for the future eradication of COVID-19.

Host traits, ownership behaviour and risk factors of SARS-CoV-2 infection in domestic pets in Mexico

SARS-CoV-2 can infect pets under natural conditions, which raises questions about the risk factors related to the susceptibility of these animals to infection. The status of pet infection by SARS-CoV-2 in Mexico is not well-understood. We aimed to estimate the frequency of positive household cats and dogs to viral RNA and antibodies for SARS-CoV-2 during the second wave of human infections in Mexico, and to recognize the major risk factors related to host and pet ownership behaviour. We evaluated two study groups, cats and dogs from COVID-19-infected/-suspected households (n = 44) and those admitted for veterinary care for any reason at several veterinary hospitals in Puebla City, Mexico (n = 91). Using RT-PCR, we identified the presence of SARS-CoV-2 RNA in swabs of four dogs (18.18%) and zero cats in COVID-19-infected/-suspected households; within this group, 31.82% of dogs and 27.27% of cats were tested IgG ELISA-positive; and neutralizing antibodies were detected in one dog (4.55%) and two cats (9.09%). In the random group (pets evaluated at private clinics and veterinary teaching hospital), 25.00% of dogs and 43.59% of cats were ELISA-positive and only one cat showed neutralizing antibodies (2.56%). Older than 4-year-old, other pets at home, and daily cleaning of pet dish, were each associated with an increase in SARS-CoV-2 infection (p < 0.05). Allowing face lick, sharing bed/food with pets and owner tested positive or suspected COVID-19 were not significant risk factors, but more than 4 h the owner spent away from home during the lockdown for COVID-19 (OR = 0.37, p = 0.01), and outdoor pet food tray (OR = 0.32, p = 0.01) significantly decreased the risks of SARS-CoV-2 infection in pets, suggesting that time the owner spends with their pet is an important risk factor.

Detection and Molecular Characterization of the SARS-CoV-2 Delta Variant and the Specific Immune Response in Companion Animals in Switzerland

In human beings, there are five reported variants of concern of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). However, in contrast to human beings, descriptions of infections of animals with specific variants are still rare. The aim of this study is to systematically investigate SARS-CoV-2 infections in companion animals in close contact with SARS-CoV-2-positive owners ("COVID-19 households") with a focus on the Delta variant. Samples, obtained from companion animals and their owners were analyzed using a real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) and next-generation sequencing (NGS). Animals were also tested for antibodies and neutralizing activity against SARS-CoV-2. Eleven cats and three dogs in nine COVID-19-positive households were RT-qPCR and/or serologically positive for the SARS-CoV-2 Delta variant. For seven animals, the genetic sequence could be determined. The animals were infected by one of the pangolin lineages B.1.617.2, AY.4, AY.43 and AY.129 and between zero and three single-nucleotide polymorphisms (SNPs) were detected between the viral genomes of animals and their owners, indicating within-household transmission between animal and owner and in multi-pet households also between the animals. NGS data identified SNPs that occur at a higher frequency in the viral sequences of companion animals than in viral sequences of humans, as well as SNPs, which were exclusively found in the animals investigated in the current study and not in their owners. In conclusion, our study is the first to describe the SARS-CoV-2 Delta variant transmission to animals in Switzerland and provides the first-ever description of Delta-variant pangolin lineages AY.129 and AY.4 in animals. Our results reinforce the need of a One Health approach in the monitoring of SARS-CoV-2 in animals.

Clinical and epidemiologic features of SARS-CoV-2 in dogs and cats compiled through national surveillance in the United States

OBJECTIVE

To characterize clinical and epidemiologic features of SARS-CoV-2 in companion animals detected through both passive and active surveillance in the US.

ANIMALS

204 companion animals (109 cats, 95 dogs) across 33 states with confirmed SARS-CoV-2 infections between March 2020 and December 2021.

PROCEDURES

Public health officials, animal health officials, and academic researchers investigating zoonotic SARS-CoV-2 transmission events reported clinical, laboratory, and epidemiologic information through a standardized One Health surveillance process developed by the CDC and partners.

RESULTS

Among dogs and cats identified through passive surveillance, 94% (n = 87) had reported exposure to a person with COVID-19 before infection. Clinical signs of illness were present in 74% of pets identified through passive surveillance and 27% of pets identified through active surveillance. Duration of illness in pets averaged 15 days in cats and 12 days in dogs. The average time between human and pet onset of illness was 10 days. Viral nucleic acid was first detected at 3 days after exposure in both cats and dogs. Antibodies were detected starting 5 days after exposure, and titers were highest at 9 days in cats and 14 days in dogs.

CLINICAL RELEVANCE

Results of the present study supported that cats and dogs primarily become infected with SARS-CoV-2 following exposure to a person with COVID-19, most often their owners. Case investigation and surveillance that include both people and animals are necessary to understand transmission dynamics and viral evolution of zoonotic diseases like SARS-CoV-2.

SARS-CoV-2 and natural infection in animals

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative agent of the novel coronavirus disease (COVID-19) pandemic, which has caused serious challenges for public health systems worldwide. Due to the close relationship between animals and humans, confirmed transmission from humans to numerous animal species has been reported. Understanding the cross-species transmission of SARS-CoV-2 and the infection and transmission dynamics of SARS-CoV-2 in different animals is crucial to control COVID-19 and protect animal health. In this review, the possible animal origins of SARS-CoV-2 and animal species naturally susceptible to SARS-CoV-2 infection are discussed. Furthermore, this review categorizes the SARS-CoV-2 susceptible animals by families, so as to better understand the relationship between SARS-CoV-2 and animals.

One-Year Surveillance of SARS-CoV-2 Exposure in Stray Cats and Kennel Dogs from Northeastern Italy

Dogs and cats are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). During the pandemic, several studies have been performed on owned cats and dogs, whereas limited data are available on the exposure to stray animals. The objective of this study was to investigate the exposure to SARS-CoV-2 of feral cats and kennel dogs in northeastern Italy, through serological and molecular methods. From May 2021 to September 2022, public health veterinary services collected serum, oropharyngeal, and rectal swab samples from 257 free-roaming dogs newly introduced to shelters, and from 389 feral cats examined during the routinely trap-neutered-return programs. The swabs were analyzed for viral RNA through a real-time reverse transcriptase PCR (rRT-PCR), and sera were tested for the presence of the specific antibody against SARS-CoV-2 (enzyme-linked immunosorbent assay). Serology was positive in nine dogs (9/257) and three cats (3/389), while two asymptomatic cats tested positive to rRT-PCR. One cat turned out to be positive both for serology and molecular analysis. In addition, this study described the case of a possible human-to-animal SARS-CoV-2 transmission in a cat that travelled in close contact to a COVID-19-positive refugee from Ukraine. This study shows that SARS-CoV-2 can infect, in natural conditions, stray cats and kennel dogs in northeastern Italy, although with a low prevalence.

Whole Genome Sequencing of SARS-CoV-2 in Cats and Dogs in South Korea in 2021

SARS-CoV-2 infections have caused unprecedented damage worldwide by affecting humans and various animals. The first reported animal infection was observed in a pet dog in Hong Kong in March 2020. 36 countries reported 692 SARS-CoV-2 infections in 25 different animal species by 31 August 2022. Most outbreaks were caused by contact with SARS-CoV-2 infected humans. In South Korea, the first SARS-CoV-2 infection in an animal was reported in a cat in February 2021. As of 31 December 2021, 74 dogs and 42 cats have been confirmed to have SARS-CoV-2 in South Korea. Here, we identified various SARS-CoV-2 genomic lineages in SARS-CoV-2 confirmed cats and dogs. Among the 40 animal samples sequenced for lineage identification, a total of eight Pango lineages (B.1.1.7 (Alpha variant), B.1.429 (Epsilon variant), B.1.470, B.1.497, B.1.619.1, B.1.620, AY.69 (Delta variant), and AY.122.5 (Delta variant)) were identified. The dominant lineages were AY.69 (Delta variant; 37.5%), B.1.497 (35.0%), and B.1.619.1 (12.5%). This study provides the first reported cases of six lineages (B.1.470, B.1.497, B.1.620, B.1.619.1, AY.69 (Delta variant)), and AY.122.5 (Delta variant) in cats and dogs. Our results emphasize the importance of monitoring SARS-CoV-2 in pets because they are dynamic hosts of variant Pango lineages of SARS-CoV-2.

SARS-CoV-2 variants of concerns in animals: An unmonitored rising health threat

Recent findings have highlighted the urgency for rapidly detecting and characterizing SARS-CoV-2 variants of concern in companion and wild animals. The significance of active surveillance and genomic investigation on these animals could pave the way for more understanding of the viral circulation and how the variants emerge. It enables us to predict the next viral challenges and prepare for or prevent these challenges. Horrible neglect of this issue could make the COVID-19 pandemic a continuous threat. Continuing to monitor the animal-origin SARS-CoV-2, and tailoring prevention and control measures to avoid large-scale community transmission in the future caused by the virus leaping from animals to humans, is essential. The reliance on only developing vaccines with ignoring this strategy could cost us many lives. Here, we discuss the most recent data about the transmissibility of SARS-CoV-2 variants of concern (VOCs) among animals and humans.

Infectious droplet exposure is an inefficient route for SARS-CoV-2 infection in the ferret model

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in humans, has a wide host range, naturally infecting felids, canids, cervids, rodents and mustelids. Transmission of SARS-CoV-2 is universally accepted to occur via contact with contaminated secretions from the respiratory epithelium, either directly or indirectly. Transmission via droplet nuclei, generated from a cough or sneeze, has also been reported in several human and experimental animal scenarios. However, the role of droplet transmission at the human-animal interface remains to be fully elucidated. Here, the ferret infection model was used to investigate the routes of infection for the SARS-CoV-2 beta variant (B.1.351). Ferrets were exposed to droplets containing infectious SARS-CoV-2, ranging between 4 and 106 µm in diameter, simulating larger droplets produced by a cough from an infected person. Following exposure, viral RNA was detected on the fur of ferrets, and was deposited onto environmental surfaces, as well as the fur of ferrets placed in direct contact; SARS-CoV-2 remained infectious on the fur for at least 48 h. Low levels of viral RNA were detected in the nasal washes early post-exposure, yet none of the directly exposed, or direct-contact ferrets, became robustly infected or seroconverted to SARS-CoV-2. In comparison, ferrets intranasally inoculated with the SARS-CoV-2 beta variant became robustly infected, shedding viral RNA and infectious virus from the nasal cavity, with transmission to 75 % of naive ferrets placed in direct contact. These data suggest that larger infectious droplet nuclei and contaminated fur play minor roles in SARS-CoV-2 transmission among mustelids and potentially other companion animals.

Detection of SARS-CoV-2 in a dog with hemorrhagic diarrhea

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has infected several animal species, including dogs, presumably via human-to-animal transmission. Most infected dogs reported were asymptomatic, with low viral loads. However, in this case we detected SARS-CoV-2 in a dog from the North African coastal Spanish city of Ceuta presenting hemorrhagic diarrhea, a disease also reported earlier on in an infected dog from the USA.

Case presentation

In early January 2021, a West Highland Terrier pet dog from Ceuta (Spain) presented hemorrhagic diarrhea with negative tests for candidate microbial pathogens. Since the animal was in a household whose members suffered SARS-CoV-2 in December 2020, dog feces were analyzed for SARS-CoV-2, proving positive in a two-tube RT-PCR test, with confirmation by sequencing a 399-nucleotide region of the spike (S) gene. Furthermore, next-generation sequencing (NGS) covered > 90% SARS-CoV-2 genome sequence, allowing to classify it as variant B.1.177. Remarkably, the sequence revealed the Ile402Val substitution in the spike protein (S), of potential concern because it mapped in the receptor binding domain (RBD) that mediates virus interaction with the cell. NGS reads mapping to bacterial genomes showed that the dog fecal microbiome fitted best the characteristic microbiome of dog’s acute hemorrhagic diarrhea.

Conclusion

Our findings exemplify dog infection stemming from the human SARS-CoV-2 pandemic, providing nearly complete-genome sequencing of the virus, which is recognized as belonging to the B.1.177 variant, adding knowledge on variant circulation in a geographic region and period for which there was little viral variant characterization. A single amino acid substitution found in the S protein that could have been of concern is excluded to belong to this category given its rarity and intrinsic nature. The dog’s pathology suggests that SARS-CoV-2 could affect the gastrointestinal tract of the dog.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03453-8.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and humoral responses against different variants of concern in domestic pet animals and stray cats from North-Eastern Spain

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19) pandemic in humans, is able to infect several domestic, captive and wildlife animal species. Since reverse zoonotic transmission to pets has been demonstrated, it is crucial to determine their role in the epidemiology of the disease to prevent further spillover events and major spread of SARS-CoV-2. In the present study, we determined the presence of virus and the seroprevalence to SARS-CoV-2, as well as the levels of neutralizing antibodies (nAbs) against several variants of concern (VOCs) in pets (cats, dogs and ferrets) and stray cats from North-Eastern of Spain. We confirmed that cats and dogs can be infected by different VOCs of SARS-CoV-2 and, together with ferrets, are able to develop nAbs against the ancestral (B.1), Alpha (B.1.1.7), Beta (B.1.315), Delta (B.1.617.2) and Omicron (BA.1) variants, with lower titres against the latest in dogs and cats, but not in ferrets. Although the prevalence of active SARS-CoV-2 infection measured as direct viral RNA detection was low (0.3%), presence of nAbs in pets living in COVID-19-positive households was relatively high (close to 25% in cats, 10% in dogs and 40% in ferrets). It is essential to continue monitoring SARS-CoV-2 infections in these animals due to their frequent contact with human populations, and we cannot discard the probability of a higher animal susceptibility to new potential SARS-CoV-2 VOCs.

Transmission dynamics and susceptibility patterns of SARS-CoV-2 in domestic, farmed and wild animals: Sustainable One Health surveillance for conservation and public health to prevent future epidemics and pandemics

The exact origin of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and source of introduction into humans has not been established yet, though it might be originated from animals. Therefore, we conducted a study to understand the putative reservoirs, transmission dynamics, and susceptibility patterns of SARS-CoV-2 in animals. Rhinolophus bats are presumed to be natural progenitors of SARS-CoV-2-related viruses. Initially, pangolin was thought to be the source of spillover to humans, but they might be infected by human or other animal species. So, the virus spillover pathways to humans remain unknown. Human-to-animal transmission has been testified in pet, farmed, zoo and free-ranging wild animals. Infected animals can transmit the virus to other animals in natural settings like mink-to-mink and mink-to-cat transmission. Animal-to-human transmission is not a persistent pathway, while mink-to-human transmission continues to be illuminated. Multiple companions and captive wild animals were infected by an emerging alpha variant of concern (B.1.1.7 lineage) whereas Asiatic lions were infected by delta variant, (B.1.617.2). To date, multiple animal species - cat, ferrets, non-human primates, hamsters and bats - showed high susceptibility to SARS-CoV-2 in the experimental condition, while swine, poultry, cattle showed no susceptibility. The founding of SARS-CoV-2 in wild animal reservoirs can confront the control of the virus in humans and might carry a risk to the welfare and conservation of wildlife as well. We suggest vaccinating pets and captive animals to stop spillovers and spillback events. We recommend sustainable One Health surveillance at the animal-human-environmental interface to detect and prevent future epidemics and pandemics by Disease X.

Viral Dynamic Surveillance in COVID-19 Patients: A Cohort Study

Background. Coronavirus disease 2019 (COVID-19) is a potentially fatal pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially those of novel SARS-CoV-2 variants and infection has affected over 700 million people globally. Methods. This retrospective, descriptive study included 118 patients admitted with SARS-CoV-2 infection as confirmed by real-time reverse transcription polymerase chain reaction. Results. The median duration of detectable SARS-CoV-2 infection in patients with high ALT, AST, and PLT/LYMPH, or low CD4+, CD8+, and PLT/MONO was considerably longer. In the risk factor model, multivariate analysis was performed for the estimation of ALT (HR, 0.54; 95% CI, 0.36-0.81), AST (HR, 0.56; 95% CI, 0.34-0.93), CD4+ (HR,0.77; 95% CI, 0.48-1.24), CD8+ (HR,0.64; 95% CI, 0.37-1.11), PLT/LYMPH (HR, 1.16; 95% CI, 0.76-1.77), and PLT/MONO (HR, 0.64; 95% CI, 0.43-0.94). Conclusions. The longer viral RNA duration was associated with a higher International Prognostic Index score ( $p=0.0013$ ), demonstrating for the first time that multivariate features of the bioindicators closely associated with SARS-CoV-2-infected patients clear the virus.

High Seroprevalence against SARS-CoV-2 among Dogs and Cats, Poland, 2021/2022

The coronavirus SARS-CoV-2 is responsible for a pandemic in the human population that has unfolded since the beginning of 2020 and has led to millions of deaths globally. Apart from humans, SARS-CoV-2 has been confirmed in various animal species, including felines, canines, mustelids, and primates. Of these species, dogs and cats are the most popular companion animals worldwide. Several seroprevalence studies have already been performed in these animal species; however, the results vary depending on the location and especially the time of sampling. Here, serum samples were collected from a total of 388 dogs and 243 cats from three veterinary clinics in two cities (Gdańsk and Olsztyn) in Poland between October 2021 and February 2022, when the country was in the midst of the fourth wave of viral spread. All sera were tested for antibodies against SARS-CoV-2 by a multispecies ELISA based on the receptor-binding domain and by an indirect immunofluorescence assay (iIFA). Overall, 18.9% of the feline sera and 16.0% of the canine sera tested positive using ELISA and iIFA. This relatively high seroprevalence among randomly selected animals is most likely related to the high case numbers in the human population and indicates a continuous occurrence of transspecies virus transmissions from infected owners to their pets. Hence, dogs and cats should be included in monitoring studies and/or outbreak investigations for a better understanding of the epidemiology of this virus.

Seroprevalence of SARS-CoV-2 in Client-Owned Cats from Portugal

The close contact between humans and domestic cats raises concerns about the potential risks of SARS-CoV-2 transmission. Thus, this study aims to investigate anti-SARS-CoV-2 seroprevalence in client-owned cats from Portugal and evaluate the infection risk of cats that maintain contact with human COVID-19 cases. A total of 176 cats, belonging to 94 households, were sampled. Cat owners answered an online questionnaire, and cats were screened for antibodies against SARS-CoV-2 using a commercial ELISA. Twenty (21.3%) households reported at least one confirmed human COVID-19 case. Forty cats (22.7%) belonged to a COVID-19-positive and 136 (77.3%) to a COVID-19-negative household. The seroprevalences of cats from COVID-19-positive and -negative households were 5.0% (2/40) and 0.7% (1/136). The two SARS-CoV-2-seropositive cats from COVID-19-positive households had an indoor lifestyle, and their owners stated that they maintained a close and frequent contact with them, even after being diagnosed with COVID-19, pointing towards human-to-cat transmission. The SARS-CoV-2-seropositive cat from the COVID-19-negative household had a mixed indoor/outdoor lifestyle and chronic diseases. Owners of the three SARS-CoV-2-seropositive cats did not notice clinical signs or behavior changes. This study highlights the low risk of SARS-CoV-2 transmission from COVID-19-positive human household members to domestic cats, even in a context of close and frequent human–animal contact.

First evidence of human-to-dog transmission of SARS-CoV-2 B.1.160 variant in France

Since the start of the coronavirus disease of 2019 (COVID-19) pandemic, several episodes of human-to-animal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission have been described in different countries. The role of pets, especially domestic dogs, in the COVID-19 epidemiology is highly questionable and needs further investigation. In this study, we report a case of COVID-19 in a French dog living in close contact with its owners who were COVID-19 patients. The dog presented rhinitis and was sampled 1 week after its owners (a man and a woman) were tested positive for COVID-19. The nasal swabs for the dog tested remained positive for SARS-CoV-2 by reverse transcription quantitative real-time PCR (RT-qPCR) 1 month following the first diagnosis. Specific anti-SARS-CoV-2 antibodies were detectable 12 days after the first diagnosis and persisted for at least 5 months as tested using enzyme-linked immunoassay (ELISA) and automated western blotting. The whole-genome sequences from the dog and its owners were 99%-100% identical (with the man and the woman's sequences, respectively) and matched the B.1.160 variant of concern (Marseille-4 variant), the most widespread in France at the time the dog was infected. This study documents the first detection of B.1.160 in pets (a dog) in France, and the first canine genome recovery of the B.1.160 variant of global concern. Moreover, given the enhanced infectivity and transmissibility of the Marseille-4 variant for humans, this case also highlights the risk that pets may potentially play a significant role in SARS-CoV-2 outbreaks and may transmit the infection to humans. We have evidence of human-to-dog transmission of the Marseille-4 variant since the owners were first to be infected. Finally, owners and veterinarians must be vigilent for canine COVID-19 when dogs are presented with respiratory clinical signs.

Risk Factors for SARS-CoV-2 Infection and Illness in Cats and Dogs1

We tested swab specimens from pets in households in Ontario, Canada, with human COVID-19 cases by quantitative PCR for SARS-CoV-2 and surveyed pet owners for risk factors associated with infection and seropositivity. We tested serum samples for spike protein IgG and IgM in household pets and also in animals from shelters and low-cost neuter clinics. Among household pets, 2% (1/49) of swab specimens from dogs and 7.7% (5/65) from cats were PCR positive, but 41% of dog serum samples and 52% of cat serum samples were positive for SARS-CoV-2 IgG or IgM. The likelihood of SARS-CoV-2 seropositivity in pet samples was higher for cats but not dogs that slept on owners’ beds and for dogs and cats that contracted a new illness. Seropositivity in neuter-clinic samples was 16% (35/221); in shelter samples, 9.3% (7/75). Our findings indicate a high likelihood for pets in households of humans with COVID-19 to seroconvert and become ill.

Geographical distribution of SARS-CoV-2 amino acids mutations and the concomitant evolution of seven distinct clades in non-human hosts

Since its first emergence in December 2019, the world has witnessed the eruption of mutations in the SARS‐CoV‐2 genome that have led to increased viral transmissibility and pathogenicity due to sustained local viral transmission. Zooanthroponotic and zoonotic transmissions have further raised concerns as they could result in the emergence of viral variants with a novel antigenicity and transmissibility that could jeopardize the vaccine efficacy. To understand the viral evolution during such transmissions, 1016 whole‐genome sequences (deposited in GISAID as of March 7, 2022) (from 18 countries) corresponding to mink, cat, deer, dog, hyena, tiger, lion, gorilla, Syrian hamster, leopard cat, fishing cat, bear cat, coati, ferret, snow leopard and green monkey have been analysed here. Intriguingly, phyloproteome analysis indicate that Nsp2:R218C, Nsp2:D268‐(deletion), Spike:D614G, Nsp12:P323L, Nsp2:A192V, ORF3a protein:Q57H, N protein:R203K and N protein:G204R/L, Spike:A222V, ORF10 protein:V30L and N protein:A220V are moderate or high recurring and clade decisive mutations, leading to 6 primary clades during the early stage of pandemic. Most interestingly, the human evolved delta variant having a combination of 26 (clade decisive) mutations defines the seventh clade and transmits to non‐human hosts across the globe without exhibiting any country‐specific mutation(s). Nonetheless, Spike:D614G and Nsp12:P323L together with (i)N protein:R203K,N protein:G204R/L,Spike:V70‐, Spike:H69‐, Nsp12:T739I, and Nsp1:M85‐, (ii)Nsp2:A192V, Nsp3:D178Y, (iii)Nsp2:T85I, N protein:P67S and ORF3a protein:Q57H and (iv)Spike:A222V, ORF10 protein:V30L, N protein:A220V and Spike:F486I are specific to Denmark, Netherlands, USA and Latvia respectively and, (v)Nsp2:D268‐ and Nsp13:R292C that are devoid of Spike:D614G and Nsp12:P323L is specific to Netherlands. SARS‐CoV‐2 variants consisting of these mutations are also seen in the human SARS‐CoV‐2 sequences from the same country. Independent country‐specific SARS‐CoV‐2 variant evolution further indicates distinct epidemiological dynamics during zooanthroponotic and zoonotic transmissions. Thus, the results presented here indicate the need for the surveillance of viral evolution in non‐human hosts also during the future pandemic.

Transmission of SARS-CoV-2 Delta variant (B.1.617.2) from a fully vaccinated human to a canine in Georgia, July 2021

SARS‐CoV‐2 infection has been described in a wide range of species, including domestic animals such as dogs and cats. Illness in dogs is usually self‐limiting, and further diagnostics may not be pursued if clinical signs resolve or they respond to empirical treatment. As new variants emerge, the clinical presentation and role in transmission may vary in animals. This report highlights different clinical presentations and immunological responses in two SARS‐CoV‐2 Delta‐variant‐positive dogs with similar exposure to the same fully vaccinated human with a SARS‐CoV‐2 infection and emphasizes the need for active surveillance and additional One Health research on SARS‐CoV‐2 variant infections in companion animals and other species.

First Detection of SARS-CoV-2 B.1.617.2 (Delta) Variant of Concern in a Symptomatic Cat in Spain

Natural and experimental SARS-CoV-2 infection in pets has been widely evidenced since the beginning of the COVID-19 pandemic. Among the numerous affected animals, cats are one of the most susceptible species. However, little is known about viral pathogenicity and transmissibility in the case of variants of concern (VOCs) in animal hosts, such as the B.1.617.2 (Delta) variant first detected in India. Here, we have identified the B.1.617.2 (Delta) VOC in a cat living with a COVID-19 positive owner. The animal presented mild symptoms (sneezing) and a high viral load was detected in the oropharyngeal swab, suggesting that an active infection was occurring in the upper respiratory tract of the cat. Transmission from the owner to the cat occurred despite the human being fully vaccinated against SARS-CoV-2. This study documents the first detection of B.1.165.2 VOC in a cat in Spain and emphasizes the importance of performing active surveillance and genomic investigation on infected animals.

Transmissibility and pathogenicity of SARS-CoV-2 variants in animal models

As of February 2022, SARS-CoV-2 is still one of the most serious public health threats due to its high mortality rate and rapid spread of novel variants. Since the first outbreak in 2019, general understanding of SARS-CoV-2 has been improved through basic and clinical studies; however, knowledge gaps still exist in our understanding of the emerging novel SARSCoV-2 variants, which impacts the corresponding development of vaccines and therapeutics. Especially, accumulation of mutations in SARS-CoV-2 and rapid spread in populations with previous immunity has resulted in selection of variants that evade the host immune response. This phenomenon threatens to render current SARS-CoV-2 vaccines ineffective for controlling the pandemic. Proper animal models are essential for detailed investigations into the viral etiology, transmission and pathogenesis mechanisms, as well as evaluation of the efficacy of vaccine candidates against recent SARS-CoV-2 variants. Further, the choice of animal model for each research topic is important for researchers to gain better knowledge of recent SARS-CoV-2 variants. Here, we review the advantages and limitations of each animal model, including mice, hamsters, ferrets, and non-human primates, to elucidate variant SARS-CoV-2 etiology and transmission and to evaluate therapeutic and vaccine efficacy.

Histopathology and localization of SARS-CoV-2 and its host cell entry receptor ACE2 in tissues from naturally infected US-farmed mink (Neovison vison)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes respiratory disease in mink similar to human COVID-19. We characterized the pathological findings in 72 mink from US farms with SARS-CoV-2 outbreaks, localized SARS-CoV-2 and its host cellular receptor angiotensin-converting enzyme 2 (ACE2) in mink respiratory tissues, and evaluated the utility of various test methods and specimens for SARS-CoV-2 detection in necropsy tissues. Of SARS-CoV-2-positive animals found dead, 74% had bronchiolitis and diffuse alveolar damage (DAD). Of euthanized SARS-CoV-2-positive animals, 72% had only mild interstitial pneumonia or minimal nonspecific lung changes (congestion, edema, macrophages); similar findings were seen in SARS-CoV-2-negative animals. Suppurative rhinitis, lymphocytic perivascular inflammation in the lungs, and lymphocytic infiltrates in other tissues were common in both SARS-CoV-2-positive and SARS-CoV-2-negative animals. In formalin-fixed paraffin-embedded (FFPE) upper respiratory tract (URT) specimens, conventional reverse transcription-polymerase chain reaction (cRT-PCR) was more sensitive than in situ hybridization (ISH) or immunohistochemistry (IHC) for detection of SARS-CoV-2. FFPE lung specimens yielded less detection of virus than FFPE URT specimens by all test methods. By IHC and ISH, virus localized extensively to epithelial cells in the nasal turbinates, and prominently within intact epithelium; olfactory mucosa was mostly spared. The SARS-CoV-2 receptor ACE2 was extensively detected by IHC within turbinate epithelium, with decreased detection in lower respiratory tract epithelium and alveolar macrophages. This study expands on the knowledge of the pathology and pathogenesis of natural SARS-CoV-2 infection in mink and supports their further investigation as a potential animal model of SARS-CoV-2 infection in humans.

Experimental Susceptibility of North American Raccoons (Procyon lotor) and Striped Skunks (Mephitis mephitis) to SARS-CoV-2

Recent spillback events of SARS-CoV-2 from humans to animals has raised concerns about it becoming endemic in wildlife. A sylvatic cycle of SARS-CoV-2 could present multiple opportunities for repeated spillback into human populations and other susceptible wildlife. Based on their taxonomy and natural history, two native North American wildlife species -the striped skunk (Mephitis mephitis) and the raccoon (Procyon lotor) -represent a high likelihood of susceptibility and ecological opportunity of becoming infected with SARS-CoV-2. Eight skunks and raccoons were each intranasally inoculated with one of two doses of the virus (103 PFU and 105 PFU) and housed in pairs. To evaluate direct transmission, a naïve animal was added to each inoculated pair 48 h post-inoculation. Four control animals of each species were handled like the experimental groups. At predetermined intervals, we collected nasal and rectal swabs to quantify virus shed via virus isolation and detect viral RNA via rRT-PCR and blood for serum neutralization. Lastly, animals were euthanized at staggered intervals to describe disease progression through histopathology and immunohistochemistry. No animals developed clinical disease. All intranasally inoculated animals seroconverted, suggesting both species are susceptible to SARS-CoV-2 infection. The highest titers in skunks and raccoons were 1:128 and 1:64, respectively. Low quantities of virus were isolated from 2/8 inoculated skunks for up to day 5 post-inoculation, however no virus was isolated from inoculated raccoons or direct contacts of either species. Neither species had gross lesions, but recovering mild chronic pneumonia consistent with viral insult was recorded histologically in 5/8 inoculated skunks. Unlike another SARS-CoV-2 infection trial in these species, we detected neutralizing antibodies in inoculated raccoons; thus, future wildlife serologic surveillance results must be interpreted with caution. Due to the inability to isolate virus from raccoons, the lack of evidence of direct transmission between both species, and low amount of virus shed by skunks, it seems unlikely for SARS-CoV-2 to become established in raccoon and skunk populations and for virus to spillback into humans. Continued outbreaks in non-domestic species, wild and captive, highlight that additional research on the susceptibility of SARS-CoV-2 in wildlife, especially musteloidea, and of conservation concern, is needed.

One Health: EAACI Position Paper on coronaviruses at the human-animal interface, with a specific focus on comparative and zoonotic aspects of SARS-CoV-2

The latest outbreak of a coronavirus disease in 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), evolved into a worldwide pandemic with massive effects on health, quality of life, and economy. Given the short period of time since the outbreak, there are several knowledge gaps on the comparative and zoonotic aspects of this new virus. Within the One Health concept, the current EAACI position paper dwells into the current knowledge on SARS-CoV-2's receptors, symptoms, transmission routes for human and animals living in close vicinity to each other, usefulness of animal models to study this disease and management options to avoid intra- and interspecies transmission. Similar pandemics might appear unexpectedly and more frequently in the near future due to climate change, consumption of exotic foods and drinks, globe-trotter travel possibilities, the growing world population, the decreasing production space, declining room for wildlife and free-ranging animals, and the changed lifestyle including living very close to animals. Therefore, both the society and the health authorities need to be aware and well prepared for similar future situations, and research needs to focus on prevention and fast development of treatment options (medications, vaccines).

Spatial epidemiology and genetic diversity of SARS-CoV-2 and related coronaviruses in domestic and wild animals

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) showed susceptibility to diverse animal species. We conducted this study to understand the spatial epidemiology, genetic diversity, and statistically significant genetic similarity along with per-gene recombination events of SARS-CoV-2 and related viruses (SC2r-CoVs) in animals globally. We collected a number of different animal species infected with SARS-CoV-2 and its related viruses. Then, we retrieved genome sequences of SARS-CoV-2 and SC2r-CoVs from GISAID and NCBI GenBank for genomic and mutational analysis. Although the evolutionary origin of SARS-CoV-2 remains elusive, the diverse SC2r-CoV have been detected in multiple Rhinolophus bat species and in Malayan pangolin. To date, human-to-animal spillover events have been reported in cat, dog, tiger, lion, gorilla, leopard, ferret, puma, cougar, otter, and mink in 25 countries. Phylogeny and genetic recombination events of SC2r-CoVs showed higher similarity to the bat coronavirus RaTG13 and BANAL-103 for most of the genes and to some Malayan pangolin coronavirus (CoV) strains for the N protein from bats and pangolin showed close resemblance to SARS-CoV-2. The clustering of animal and human strains from the same geographical area has proved human-to-animal transmission of the virus. The Alpha, Delta and Mu-variant of SARS-CoV-2 was detected in dog, gorilla, lion, tiger, otter, and cat in the USA, India, Czech Republic, Belgium, and France with momentous genetic similarity with human SARS-CoV-2 sequences. The mink variant mutation (spike_Y453F) was detected in both humans and domestic cats. Moreover, the dog was affected mostly by clade O (66.7%), whereas cat and American mink were affected by clade GR (31.6 and 49.7%, respectively). The α-variant was detected as 2.6% in cat, 4.8% in dog, 14.3% in tiger, 66.7% in gorilla, and 77.3% in lion. The highest mutations observed in mink where the substitution of D614G in spike (95.2%) and P323L in NSP12 (95.2%) protein. In dog, cat, gorilla, lion, and tiger, Y505H and Y453F were the common mutations followed by Y145del, Y144del, and V70I in S protein. We recommend vaccine provision for pet and zoo animals to reduce the chance of transmission in animals. Besides, continuous epidemiological and genomic surveillance of coronaviruses in animal host is crucial to find out the immediate ancestor of SARS-CoV-2 and to prevent future CoVs threats to humans.

SARS-CoV-2 vaccine for domestic and captive animals: An effort to counter COVID-19 pandemic at the human-animal interface

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has already affected millions worldwide. The emergence of multiple SARS-CoV-2 variants may pose a significant threat to our efforts in controlling the pandemic. The impact of SARS-CoV-2 variants on the efficacy of available vaccines, therapeutics, and diagnostics is currently being investigated. SARS-CoV-2 has been implicated to be originated from animals due to cross-species jumping and raises zoonotic concerns due to the potential for reintroduction into the human populations via interspecies transmission between humans and animals. Natural SARS-CoV-2 infections have been reported in domestic animals (dog, cat, and ferret), captive animals (tiger, lion, snow leopard, puma, otter, and gorilla), and wild and farmed minks. Vaccination of domestic animals can prevent the possible introduction of SARS-CoV-2 into the feral population and subsequent transmission to wildlife. Although the need to vaccinate susceptible animal species, such as cats, minks, and great apes, might seem irrational from a public health standpoint, the successful elimination of SARS-CoV-2 will only be possible by controlling the transmission in all susceptible animal species. This is necessary to prevent the re-emergence of SARS-CoV-2 in the future.

Genomic investigation of a household SARS-CoV-2 disease cluster in Arizona involving a cat, dog, and pet owner

Arizona's COVID-19 and Pets Program is a prospective surveillance study being conducted to characterize how SARS-CoV-2 impacts companion animals living in households with SARS-CoV-2-positive individuals. Among the enrolled pets, we identified a SARS-CoV-2-infected cat and dog from the same household; both animals were asymptomatic but had close contact with the symptomatic and SARS-CoV-2-positive owner. Whole genome sequencing of animal and owner specimens revealed identical viral genomes of the B.1.575 lineage, suggesting zoonotic transmission of SARS-CoV-2 from human to at least one pet. This is the first report of the B.1.575 lineage in companion animals. Genetically linking SARS-CoV-2 between people and animals, and tracking changes in SARS-CoV-2 genomes is essential to detect any cross-species SARS-CoV-2 transmission that may lead to more transmissible or severe variants that can affect humans. Surveillance studies, including genomic analyses of owner and pet specimens, are needed to further our understanding of how SARS-CoV-2 impacts companion animals.

SARS-CoV-2 B.1.1.7 Variant Infection in Malayan Tigers, Virginia, USA

We report infection of 3 Malayan tigers with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.7 (Alpha) variant at a zoologic park in Virginia, USA. All tigers exhibited respiratory signs consistent with SARS-CoV-2 infection. These findings show that tigers are susceptible to infection with the SARS-CoV-2 B.1.1.7 variant.

SARS-CoV-2 Infection in One Cat and Three Dogs Living in COVID-19-Positive Households in Madrid, Spain

In this study, we describe SARS-CoV-2 infection dynamics in one cat and three dogs from households with confirmed human cases of COVID-19 living in the Madrid Community (Spain) at the time of expansion (December 2020 through June 2021) of the alpha variant (lineage B.1.1.7). A thorough physical exam and nasopharyngeal, oropharyngeal, and rectal swabs were collected for real-time reverse-transcription PCR (RT-qPCR) SARS-CoV-2 testing on day 0 and in successive samplings on days 7, 14, 21, and 47 during monitoring. Blood was also drawn to determine complete blood counts, biochemical profiles, and serology of the IgG response against SARS-CoV-2. On day 0, the cat case 1 presented with dyspnea and fever associated with a mild bronchoalveolar pattern. The dog cases 2, 3, and 4 were healthy, but case 2 presented with coughing, dyspnea, and weakness, and case 4 exhibited coughing and bilateral nasal discharge 3 and 6 days before the clinical exam. Case 3 (from the same household as case 2) remained asymptomatic. SARS-CoV-2 detection by RT-qPCR showed that the cat case 1 and the dog case 2 exhibited the lowest cycle threshold (Ct) (Ct < 30) when they presented clinical signs. Viral detection failed in successive samplings. Serological analyses revealed a positive IgG response in cat case 1 and dog cases 3 and 4 shortly after or simultaneously to virus shedding. Dog case 2 was seronegative, but seroconverted 21 days after SARS-CoV-2 detection. SARS-CoV-2 genome sequencing was attempted, and genomes were classified as belonging to the B.1.1.7 lineage.

Myocarditis and Subclinical-Like Infection Associated With SARS-CoV-2 in Two Cats Living in the Same Household in France: A Case Report With Literature Review

This report provides the first clinical, radiographic, echocardiographic, and biological description of SARS-CoV-2-associated myocarditis with a 6-month follow-up in a 5-year-old obese male domestic shorthair cat (Cat-1) presented for refractory congestive heart failure, with high cardiac troponin-I level (5.24 ng/ml), and a large lingual ulcer. The animal was SARS-CoV-2 positive on serology. The other cat living in the same household (Cat-2) never showed any clinical sign but was also confirmed SARS-CoV-2 positive on serology. Both cats were SARS-CoV-2 PCR negative. Cat-1 had closer contact than Cat-2 with their owner, who had been in close contact with a coworker tested PCR positive for COVID-19 (Alpha (B.1.1.7) variant) 4 weeks before Cat-1's first episode of congestive heart failure. A focused point-of-care echocardiography at presentation revealed for Cat-1 numerous B-lines, pleural effusion, severe left atrial dilation and dysfunction, and hypertrophic cardiomyopathy phenotype associated with focal pulmonary consolidations. Both myocarditis and pneumonia were suspected, leading to the prescription of cardiac medications and antibiotics. One month later, Cat-1 recovered, with normalization of left atrial size and function, and radiographic and echocardiography disappearance of heart failure signs and pulmonary lesions. An extensive literature review of SARS-CoV-2-related cardiac injury in pets in comparison with human pathology is discussed.

Infection with SARS-CoV-2 variant B.1.1.7 detected in a group of dogs and cats with suspected myocarditis

BACKGROUND

Domestic pets can contract severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; however, it is unknown whether the UK B.1.1.7 variant can more easily infect certain animal species or increase the possibility of human-to-animal transmission.

METHODS

This is a descriptive case series reporting SARS-CoV-2 B.1.1.7 variant infections in a group of dogs and cats with suspected myocarditis.

RESULTS

The study describes the infection of domestic cats and dogs by the B.1.1.7 variant. Two cats and one dog were positive to SARS-CoV-2 PCR on rectal swab, and two cats and one dog were found to have SARS-CoV-2 antibodies 2-6 weeks after they developed signs of cardiac disease. Many owners of these pets had developed respiratory symptoms 3-6 weeks before their pets became ill and had also tested positive for COVID-19. Interestingly, all these pets were referred for acute onset of cardiac disease, including severe myocardial disorders of suspected inflammatory origin but without primary respiratory signs.

CONCLUSIONS

These findings demonstrate, for the first time, the ability for pets to be infected by the B.1.1.7 variant and question its possible pathogenicity in these animals.

Near-Complete Genome of SARS-CoV-2 Delta (AY.3) Variant Identified in a Dog in Kansas, USA

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) descriptions of infection and transmission have been increasing in companion animals in the past year. Although canine susceptibility is generally considered low, their role in the COVID-19 disease cycle remains unknown. In this study, we detected and sequenced a delta variant (AY.3) from a 12-year-old Collie living with owners that previously tested positive for SARS-CoV-2. It is unclear if the dogs' symptoms were related to SARS-CoV-2 infection or underlying conditions. The whole genome sequence obtained from the dog sample had several unique consensus level changes not previously identified in a SARS-CoV-2 genome that may play a role in the rapid adaptation from humans to dogs. Within the spike coding region, 5/7 of the subconsensus variants identified in the dog sequence were also identified in the closest in-house human reference case. Taken together, the whole genome sequence, and phylogenetic and subconsensus variant analyses indicate the virus infecting the animal originated from a local outbreak cluster. The results of these analyses emphasize the importance of rapid detection and characterization of SARS-CoV-2 variants of concern in companion animals.

Lack of Evidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spillover in Free-Living Neotropical Non-Human Primates, Brazil

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent of coronavirus disease 2019 (COVID-19), is responsible for the worst pandemic of the 21st century. Like all human coronaviruses, SARS-CoV-2 originated in a wildlife reservoir, most likely from bats. As SARS-CoV-2 has spread across the globe in humans, it has spilled over to infect a variety of non-human animal species in domestic, farm, and zoo settings. Additionally, a broad range of species, including one neotropical monkey, have proven to be susceptible to experimental infection with SARS-CoV-2. Together, these findings raise the specter of establishment of novel enzootic cycles of SARS-CoV-2. To assess the potential exposure of free-living non-human primates to SARS-CoV-2, we sampled 60 neotropical monkeys living in proximity to Manaus and São José do Rio Preto, two hotspots for COVID-19 in Brazil. Our molecular and serological tests detected no evidence of SAR-CoV-2 infection among these populations. While this result is reassuring, sustained surveillance efforts of wildlife living in close association with human populations is warranted, given the stochastic nature of spillover events and the enormous implications of SARS-CoV-2 spillover for human health.

Evolutionary Dynamics and Epidemiology of Endemic and Emerging Coronaviruses in Humans, Domestic Animals, and Wildlife

Diverse coronavirus (CoV) strains can infect both humans and animals and produce various diseases. CoVs have caused three epidemics and pandemics in the last two decades, and caused a severe impact on public health and the global economy. Therefore, it is of utmost importance to understand the emergence and evolution of endemic and emerging CoV diversity in humans and animals. For diverse bird species, the Infectious Bronchitis Virus is a significant one, whereas feline enteric and canine coronavirus, recombined to produce feline infectious peritonitis virus, infects wild cats. Bovine and canine CoVs have ancestral relationships, while porcine CoVs, especially SADS-CoV, can cross species barriers. Bats are considered as the natural host of diverse strains of alpha and beta coronaviruses. Though MERS-CoV is significant for both camels and humans, humans are nonetheless affected more severely. MERS-CoV cases have been reported mainly in the Arabic peninsula since 2012. To date, seven CoV strains have infected humans, all descended from animals. The severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) are presumed to be originated in Rhinolopoid bats that severely infect humans with spillover to multiple domestic and wild animals. Emerging alpha and delta variants of SARS-CoV-2 were detected in pets and wild animals. Still, the intermediate hosts and all susceptible animal species remain unknown. SARS-CoV-2 might not be the last CoV to cross the species barrier. Hence, we recommend developing a universal CoV vaccine for humans so that any future outbreak can be prevented effectively. Furthermore, a One Health approach coronavirus surveillance should be implemented at human-animal interfaces to detect novel coronaviruses before emerging to humans and to prevent future epidemics and pandemics.

Detection of SARS-CoV-2 variant B.1.1.7 in a cat in Germany

Several non-variant of concern SARS-CoV-2 infections in pets have been reported as documented in the OIE and GISAID databases and there is only one fully documented case of an alpha variant of concern (VOC)(B.1.1.7) in the United States so far. Here, we describe the first case in a cat infected with the alpha SARS-CoV-2 variant in Germany. A cat suffering from pneumonia was presented to a veterinary practice. The pneumonia was treated symptomatically, but 16 days later the cat was presented again. Since the owner had been tested positive for a SARS-CoV-2 infection in the meantime, swab samples were taken from the cat and analyzed for SARS-CoV-2 specific nucleic acids. The various RT-qPCR analyses and whole-genome sequencing revealed the presence of the SARS-CoV-2 B.1.1.7 variant in this cat. This study shows that pets living in close contact with SARS-CoV-2 B.1.1.7 infected owners can contract this virus and also suffer from a respiratory disease. It is not clear yet whether onward transmissions to other cats and humans can occur. To minimize transmission risks, pet owners and veterinarians should comply to the hygienic rules published by OIE and others. It must be stated, that infections of cats with SARS-CoV-2 is still a rare event. Cats with clinical signs of a respiratory disease should be presented to a veterinarian, who will decide on further steps.

One Health Investigation of SARS-CoV-2 Infection and Seropositivity among Pets in Households with Confirmed Human COVID-19 Cases-Utah and Wisconsin, 2020

Approximately 67% of U.S. households have pets. Limited data are available on SARS-CoV-2 in pets. We assessed SARS-CoV-2 infection in pets during a COVID-19 household transmission investigation. Pets from households with ≥1 person with laboratory-confirmed COVID-19 were eligible for inclusion from April-May 2020. We enrolled 37 dogs and 19 cats from 34 households. All oropharyngeal, nasal, and rectal swabs tested negative by rRT-PCR; one dog's fur swabs (2%) tested positive by rRT-PCR at the first sampling. Among 47 pets with serological results, eight (17%) pets (four dogs, four cats) from 6/30 (20%) households had detectable SARS-CoV-2 neutralizing antibodies. In households with a seropositive pet, the proportion of people with laboratory-confirmed COVID-19 was greater (median 79%; range: 40-100%) compared to households with no seropositive pet (median 37%; range: 13-100%) (p = 0.01). Thirty-three pets with serologic results had frequent daily contact (≥1 h) with the index patient before the person's COVID-19 diagnosis. Of these 33 pets, 14 (42%) had decreased contact with the index patient after diagnosis and none were seropositive; of the 19 (58%) pets with continued contact, four (21%) were seropositive. Seropositive pets likely acquired infection after contact with people with COVID-19. People with COVID-19 should restrict contact with pets and other animals.

Report of One-Year Prospective Surveillance of SARS-CoV-2 in Dogs and Cats in France with Various Exposure Risks: Confirmation of a Low Prevalence of Shedding, Detection and Complete Sequencing of an Alpha Variant in a Cat

Despite the probable zoonotic origin of SARS-CoV-2, only limited research efforts have been made to understand the role of companion animals in SARS-CoV-2 epidemiology. According to recent serological prevalence studies, human-to-companion animal transmission is quite frequent, which led us to consider that the risk of SARS-CoV-2 transmission from animal to human, albeit negligible in the present context, may have been underestimated. In this study, we provide the results of a prospective survey that was conducted to evaluate the SARS-CoV-2 isolation rate by qRT-PCR in dogs and cats with different exposure risks and clinical statuses. From April 2020 to April 2021, we analyzed 367 samples and investigated the presence of SARS-CoV-2 RNA using qRT-PCR. Only four animals tested positive, all of them being cats. Three cats were asymptomatic and one presented a coryza-like syndrome. We describe in detail the infection in two cats and the associated clinical characteristics. Importantly, we obtained SARS-CoV-2 genomes from one infected animal and characterized them as Alpha variants. This represents the first identification of the SARS-CoV-2 Alpha variant in an infected animal in France.

First Detection of SARS-CoV-2 B.1.1.7 Variant of Concern in an Asymptomatic Dog in Spain

Natural SARS-CoV-2 infection in pets has been widely documented during the last year. Although the majority of reports suggested that dogs’ susceptibility to the infection is low, little is known about viral pathogenicity and transmissibility in the case of variants of concern, such as B.1.1.7 in this species. Here, as part of a large-scale study on SARS-CoV-2 prevalence in pets in Spain, we have detected the B.1.1.7 variant of concern (VOC) in a dog whose owners were infected with SARS-CoV-2. The animal did not present any symptoms, but viral loads were high in the nasal and rectal swabs. In addition, viral isolation was possible from both swabs, demonstrating that the dog was shedding infectious virus. Seroconversion occurred 23 days after the first sampling. This study documents the first detection of B.1.1.7 VOC in a dog in Spain and emphasizes the importance of performing active surveillance and genomic investigation on infected animals.

SARS-CoV-2 B.1.1.7 variant of concern detected in a pet dog and cat after exposure to a person with COVID-19, USA

As part of a longitudinal household transmission study of pets living with persons with COVID‐19 in Texas, two pets were confirmed to be infected with the SARS‐CoV‐2 B.1.1.7 variant of concern (VOC). The pets were a dog and a cat from the same household, sampled two days after their owner tested positive for COVID‐19. The oral, nasal and fur swabs for both pets tested positive for SARS‐CoV‐2 by qRT‐PCR and consensus whole‐genome sequences from the dog and cat were 100% identical and matched the B.1.1.7 VOC. Virus was isolated from the cat's nasal swab. One month after initial detection of infection, the pets were re‐tested twice at which time only the fur swabs (both pets) and oral swab (dog only) remained positive, and neutralizing antibodies for SARS‐CoV‐2 were present in both animals. Sneezing by both pets was noted by the owner in the weeks between initial and follow‐up testing. This study documents the first detection of B.1.1.7. in companion animals in the United States, and the first genome recovery and isolation of B.1.1.7 variant of concern globally in any animal.