Prevalence of natural feline coronavirus infection in domestic cats in Fujian, China.

Only few studies have investigated the prevalence of feline coronavirus (FCoV) infection in domestic cats in Fujian, China. This is the first study to report the prevalence rate of FCoV infection in domestic cats in Fujian, China, and to analyse the epidemiological characteristics of FCoV infection in the region. A total of 112 cat faecal samples were collected from animal hospitals and catteries in the Fujian Province. RNA was extracted from faecal material for reverse transcription polymerase chain reaction (RT-PCR). The prevalence rate of FCoV infection was determined, and its epidemiological risk factors were analysed. The overall prevalence of FCoV infection in the cats, was 67.9%. We did not observe a significant association between the age, sex, or breed of the cats included in the study and the prevalence rate of the viral infection. Phylogenetic analysis showed that the four strains from Fujian were all type I FCoV. This is the first study to analyse the prevalence and epidemiological characteristics of FCoV infection in domestic cats in Fujian, China, using faecal samples. The results of this study provide preliminary data regarding the prevalence of FCoV infection in the Fujian Province for epidemiological studies on FCoV in China and worldwide. Future studies should perform systematic and comprehensive epidemiological investigations to determine the prevalence of FCoV infection in the region.

AN OUTBREAK OF FELINE INFECTIOUS PERITONITIS IN THREE RELATED SAND CATS (FELIS MARGARITA) IN HUMAN CARE.

Feline infectious peritonitis (FIP) is a systemic disease in felid species caused by infection with mutated forms of feline coronavirus (FCoV), and outbreaks can devastate exotic felid populations in human care. Feline infectious peritonitis was diagnosed in three of four related juvenile sand cats (Felis margarita) from a single institution over a 6-wk period. Case 1 was a 7-mon-old male found deceased with no premonitory signs. Case 2, an 8-mon-old male (littermate to Case 1), and Case 3, a 6-mon-old male (from a different litter with identical parentage), were evaluated for lethargy and anorexia 1 mon after Case 1. Both exhibited transient anisocoria and progressive lethargy, anorexia, and dehydration despite antibiotic and supportive treatment. Approximately 1 wk after initial presentation, Case 2 was humanely euthanized, and Case 3 was found deceased. Necropsy findings included intrathoracic and/or intra-abdominal lymphadenopathy (3/3 cases), bicavitary effusion (2/3), multifocal tan hepatic and intestinal nodules (1/3), and multifocal yellow renal nodules (1/3). Histologically, all cats had severe pyogranulomatous vasculitis in multiple organs, and the presence of FCoV antigen was confirmed using immunohistochemical staining. Next-generation sequencing of the virus from Case 3's affected kidney demonstrated ∼93% homology to the UG-FH8 virus, a serotype 1 feline alphacoronavirus isolated from Denmark. Future research will focus on comparative viral genomic sequencing with the goals of identifying potential sources of FCoV infection and identifying features that may have contributed to the development of FIP in this species.

Role of Feline Coronavirus as Contributor to Diarrhea in Cats from Breeding Catteries.

(1) Background: Feline coronavirus infection (FCoV) is common in multi-cat environments. A role of FCoV in causing diarrhea is often assumed, but has not been proven. The aim of this study was to evaluate an association of FCoV infection with diarrhea in multi-cat environments. (2) Methods: The study included 234 cats from 37 catteries. Fecal samples were analyzed for FCoV RNA by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR). Potential co-infections were determined by applying a qPCR panel on different potential enteropathogens and fecal flotation. A fecal scoring system was used to categorize feces as diarrheic or non-diarrheic. (3) Results: Of the 234 cats included, 23 had diarrhea. The prevalence of FCoV infection was 87.0% in cats with and 58.8% in cats without diarrhea. FCoV infection was significantly associated with diarrhea (Odds Ratio (OR) 5.01; p = 0.008). In addition, presence of Clostridium perfringens α toxin (OR 6.93; p = 0.032) and feline panleukopenia virus (OR 13.74; p = 0.004) were associated with an increased risk of diarrhea. There was no correlation between FCoV load and fecal score. FCoV-positive cats with co-infections were not more likely to have diarrhea than FCoV-positive cats without co-infections (p = 0.455). (4) Conclusions: FCoV infection is common in cats from catteries and can be associated with diarrhea.

Molecular epidemiology of type I and II feline coronavirus from cats with suspected feline infectious peritonitis in China between 2019 and 2021.

Feline infectious peritonitis (FIP) is one of the deadliest diseases of cats in China. In this study, 120 ascitic fluid samples from FIP-suspected cats were collected from veterinary hospitals in 21 provinces in China between 2019 and 2021. One hundred nine samples were positive for feline coronavirus (FCoV), with no feline immunodeficiency virus infections and one feline leukemia virus infection (1/109, 0.92%). The prevalence of FCoV was significantly associated with age (p < 0.01) and was not highly associated with gender, breed, geographical location, or viral coinfection (p > 0.01). One unique strain, SD/202012/003, contained a six-nucleotide deletion in the spike gene. Sequence analysis showed that 94.68% (89/94) of the isolates had a mutation of methionine to leucine at position 1058 in the spike protein. The epidemiological data obtained of FCoV in this study may be beneficial for clinical monitoring of FCoV in China.

Prevalence and molecular characteristics of feline coronavirus in southwest China from 2017 to 2020.

Feline coronavirus (FCoV) is the causative agent of feline infectious peritonitis and diarrhoea in kittens worldwide. In this study, a total of 173 feline diarrhoeal faecal and ascetic samples were collected from 15 catteries and six veterinary hospitals in southwest China from 2017 to 2020. FCoV was detected in 80.35 % (139/173) of the samples using the RT-nPCR method; these included infections with 122 type I FCoV and 57 type II FCoV. Interestingly, 51 cases had co-infection with types I and II, the first such report in mainland China. To further analyse the genetic diversity of FCoV, we amplified 23 full-length spike (S) genes, including 18 type I and five type II FCoV. The type I FCoV and type II FCoV strains shared 85.5-98.7% and 97.4-98.9% nucleotide (nt) sequence identities between one another, respectively. The N-terminal domain (NTD) of 23 FCoV strains showed a high degree of variation (73.6-80.3 %). There was six type I FCoV strains with two amino acid insertions (159HL160) in the NTD. In addition, 18 strains of type I FCoV belonged to the Ie cluster, and five strains of type II FCoV were in the IIb cluster based on phylogenetic analysis. Notably, it was first time that two type I FCoV strains had recombination in the NTD, and the recombination regions was located 140-857 nt of the S gene. This study constitutes a systematic investigation of the current infection status and molecular characteristics of FCoV in southwest China.

FELINE CORONAVIRUS AND FELINE INFECTIOUS PERITONITIS IN NONDOMESTIC FELID SPECIES.

Feline coronavirus (FCoV) is reported worldwide and known to cause disease in domestic and nondomestic felid species. Although FCoV often results in mild to inapparent disease, a small subset of cats succumb to the fatal, systemic disease feline infectious peritonitis (FIP). An outbreak of FIP in Cheetahs (Acinonyx jubatus) in a zoological collection demonstrated the devastating effect of FCoV introduction into a naïve group of animals. In addition to cheetahs, FIP has been described in European wildcats (Felis silvestris), a tiger (Panthera tigris), a mountain lion (Puma concolor), and lion (Panthera leo). This paper reviews the reported cases of FIP in nondomestic felid species and highlights the surveys of FCoV in populations of nondomestic felids.

Feline infectious peritonitis (FIP) and coronavirus disease 19 (COVID-19): Are they similar?

SARS-CoV-2 has radically changed our lives causing hundreds of thousands of victims worldwide and influencing our lifestyle and habits. Feline infectious peritonitis (FIP) is a disease of felids caused by the feline coronaviruses (FCoV). FIP has been considered irremediably deadly until the last few years. Being one of the numerous coronaviruses that are well known in veterinary medicine, information on FCoV could be of interest and might give suggestions on pathogenic aspects of SARS-CoV-2 that are still unclear. The authors of this paper describe the most important aspects of FIP and COVID-19 and the similarities and differences between these important diseases. SARS-CoV-2 and FCoV are taxonomically distant viruses, and recombination events with other coronaviruses have been reported for FCoV and have been suggested for SARS-CoV-2. SARS-CoV-2 and FCoV differ in terms of some pathogenic, clinical and pathological features. However, some of the pathogenic and immunopathogenic events that are well known in cats FIP seem to be present also in people with COVID-19. Moreover, preventive measures currently recommended to prevent SARS-CoV-2 spreading have been shown to allow eradication of FIP in feline households. Finally, one of the most promising therapeutic compounds against FIP, GS-441524, is the active form of Remdesivir, which is being used as one therapeutic option for COVID-19.

Prevalence of Feline Coronavirus Shedding in German Catteries and Associated Risk Factors.

The aim of this prospective study was to determine prevalence and potential risk factors of feline coronavirus (FCoV) shedding. Four consecutive fecal samples of 179 cats from 37 German breeding catteries were analyzed for FCoV ribonucleic acid (RNA) by real-time reverse transcriptase polymerase chain reaction (RT-qPCR). Prevalence of shedding was calculated using different numbers of fecal samples per cat (1-4) and different sampling intervals (5-28 days). Information on potential risk factors for FCoV shedding was obtained by a questionnaire. Risk factor analysis was performed using a generalized linear mixed model (GLMM). Most cats (137/179, 76.5%, 95% confidence interval (CI) 69.8-82.2) shed FCoV at least at once. None of the tested 37 catteries was free of FCoV. Prevalence calculated including all four (76.5%, 95% CI 69.8-82.2) or the last three (73.7%, 95% CI 66.8-79.7) samples per cat was significantly higher than the prevalence calculated with only the last sample (61.5%, 95% CI 54.2-68.3; p = 0.0029 and 0.0175, respectively). Young age was significantly associated with FCoV shedding while the other factors were not. For identification of FCoV shedders in multi-cat households, at least three fecal samples per cat should be analyzed. Young age is the most important risk factor for FCoV shedding.

Coronavirus Infections in Companion Animals: Virology, Epidemiology, Clinical and Pathologic Features.

Coronaviruses are enveloped RNA viruses capable of causing respiratory, enteric, or systemic diseases in a variety of mammalian hosts that vary in clinical severity from subclinical to fatal. The host range and tissue tropism are largely determined by the coronaviral spike protein, which initiates cellular infection by promoting fusion of the viral and host cell membranes. Companion animal coronaviruses responsible for causing enteric infection include feline enteric coronavirus, ferret enteric coronavirus, canine enteric coronavirus, equine coronavirus, and alpaca enteric coronavirus, while canine respiratory coronavirus and alpaca respiratory coronavirus result in respiratory infection. Ferret systemic coronavirus and feline infectious peritonitis virus, a mutated feline enteric coronavirus, can lead to lethal immuno-inflammatory systemic disease. Recent human viral pandemics, including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and most recently, COVID-19, all thought to originate from bat coronaviruses, demonstrate the zoonotic potential of coronaviruses and their potential to have devastating impacts. A better understanding of the coronaviruses of companion animals, their capacity for cross-species transmission, and the sharing of genetic information may facilitate improved prevention and control strategies for future emerging zoonotic coronaviruses. This article reviews the clinical, epidemiologic, virologic, and pathologic characteristics of nine important coronaviruses of companion animals.

Origin and transmission of Feline coronavirus type I in domestic cats from Northern Italy: a phylogeographic approach.

Feline coronavirus (FCoV) is responsible, along with an inadequate immune response of the host, for Feline infectious peritonitis (FIP), one of the most frequent and deadly infectious feline disease worldwide. This study analyzed the genetic characteristics of the spike (S) gene of 33 FCoVs circulating in Northern Italy between 2011 and 2015 in cats with or without FIP. In order to reconstruct the most probable places of origin and dispersion of FCoV among Italian cats, a phylogeographic approach was performed based on 106 FCoV S gene partial sequences from cats, including the 33 novel Italian sequences and 73 retrieved from public databases. Only FCoV type I was found in the Italian cats. The estimated mean evolutionary rate of FCoV was 2.4 × 10-2 subs/site/year (95% HPD: 1.3-3.7 × 10-2), confirming the high genetic variability in the circulating strains. All the isolates clustered in a unique highly significant clade that likely originated from USA between the 1950s and the 1970s, confirming the first descriptions of the disease in American cats. Our results suggest that from USA the virus likely entered Germany and thereafter spread to other European countries. Phylogeography showed that sequences segregated mainly by geographical origin. In the 2010s Italian sequences clustered in different subclades, confirming that different strains cocirculate in Italy. Further studies on archival samples and other genetic regions of FCoV are suggested in order to confirm the present results and to reconstruct a more in-depth detailed virus dispersion pattern for the definition of possible control measures.

Prevalence and mutation analysis of the spike protein in feline enteric coronavirus and feline infectious peritonitis detected in household and shelter cats in western Canada.

Feline infectious peritonitis (FIP) is a fatal disease for which no simple antemortem diagnostic assay is available. A new polymerase chain reaction (PCR) test has recently been developed that targets the spike protein region of the FIP virus (FIPV) and can identify specific mutations (M1030L or S1032A), the presence of which indicates a shift from feline enteric coronavirus (FeCV) to FIPV. This test will only be useful in the geographical region of interest, however, if the FIP viruses contain these mutations. The primary objective of this study was to determine the presence of the M1030L or S1032A mutations in FeCV derived from stool samples from a selected group of healthy cats from households and shelters and determine how many of these cats excrete FeCV. The secondary objective was to evaluate how often these specific FIPV mutations were present in tissue samples derived from cats diagnosed with FIP at postmortem examination. Feline enteric coronavirus (FeCV) was detected in 46% of fecal samples (86/185), all were FeCV type 1, with no difference between household or shelter cats. Only 45% of the FIPV analyzed contained the previously reported M1030L or S1032A mutations. It should be noted that, as the pathological tissue samples were opportunistically obtained and not specifically obtained for PCR testing, caution is warranted in interpreting these data.

La péritonite infectieuse féline (FIP) est une maladie fatale pour laquelle il n'existe pas de test diagnostique ante-mortem simple. Une nouvelle épreuve d'amplification en chaîne par la polymérase (PCR) a récemment été développée et qui vise la région de la protéine de spicule du virus FIP (FIPV) et peut identifier les mutations spécifiques (M1030L ou S1032A), la présence desquelles indique un glissement du coronavirus entérique félin (FeCV) vers le FIPV. Cette épreuve sera utile uniquement dans la région géographique d'intérêt, toutefois, si les virus FIP ont ces mutations. L'objectif premier de la présente étude était de déterminer la présence des mutations M1030L ou S1032A chez FeCV obtenu d'échantillons de fèces provenant d'un groupe sélectionné de chats en santé issus de maisonnée et refuges et de déterminer combien de ces chats excrètent FeCV. L'objectif secondaire était d'évaluer à quelle fréquence ces mutations spécifiques de FIPV étaient présentes dans des échantillons de tissu provenant de chats diagnostiqués avec FIP lors d'examen post-mortem. Le FeCV fut détecté dans 46 % des échantillons fécaux (86/185), tous de type FeCV 1, et aucune différence notée entre les chats de maisonnée ou de refuge. Seulement 45 % des FIPV analysés contenaient les mutations M1030L ou S1032A rapportées précédemment. Il faut noter que, étant donné que les échantillons de tissus pathologiques furent obtenus de manière opportuniste et non spécifiquement obtenus pour analyse par PCR, l'interprétation des résultats est à faire avec précaution.(Traduit par Docteur Serge Messier).

Epidemiological investigation of feline infectious peritonitis in cats living in Harbin, Northeast China from 2017 to 2019 using a combination of an EvaGreen-based real-time RT-PCR and serum chemistry assays.

Feline infectious peritonitis (FIP) is caused by the FIP virus (FIPV), a highly virulent mutant form of feline coronavirus (FCoV). This disease is one of the most important infectious diseases in cats, and it is associated with high mortality, particularly among younger cats. In this study, we isolated a wild-type FIPV HRB-17 epidemic strain from the blood sample of household pet cat exhibiting the characteristic wet-form FIP symptoms, which has been confirmed further by animal infection. Further, we developed an EvaGreen-based real-time RT-PCR assay for the accurate detection of FCoV based on the amplification of the highly conserved FIPV N gene. Then, using a combination of the real-time RT-PCR approach and a serum chemistry assay, we performed an epidemiological survey of FIPV infection in cats living in Harbin City, Northeast China. The results indicated that the EvaGreen-based real-time RT-PCR assay can be used for screening FCoV infection in the affected cats at an analytical detection limit of 8.2 × 101 viral genome copies/µL, but could not effectively distinguish FIPVs from FECVs. Additionally, the results of the epidemiological survey investigating feline blood samples (n = 1523) collected between July 2017 to July 2019 revealed an FIPV prevalence of approximately 12% (189/1523). Maybe, the prevalence would be less than 12% due to the real-time RT-PCR assay could not accurately differentiate FIPV and FECV. Nevertheless, it still highlighted the severity of the FIP epidemic in cats and reiterated the urgent need to develop effective anti-FIP therapeutic agents and anti-FIPV vaccines. As pet cats are household animals, risk communication and continuous region-extended surveillance cat programs are recommended.

Feline coronavirus isolates from a part of Brazil: insights into molecular epidemiology and phylogeny inferred from the 7b gene.

The Feline coronavirus (FCoV) can lead to Feline infectious peritonitis (FIP), which the precise cause is still unknown. The theory of internal mutation suggests that a less virulent biotype of FCoV (FECV) would lead to another more pathogenic biotype (FIPV) capable of causing FIP. In this work, the 7b gene was amplified from 51 domestic cat plasma samples by semi-nested PCR and tested through phylogenetic and phylogeographical approaches. The 7b gene of Brazilian isolates displayed high conservation, a strong correlation between the geographic origin of the viral isolates and their genealogy, and its evolution was possibly shaped by a combination of high rates of nucleotide substitution and purifying selection.

Causes of death and euthanasia in domestic cats in the Santa Catarina plateau (1995-2015) / Causas de morte e eutanásia em felinos domésticos no Planalto de Santa Catarina (1995-2015)

Knowledge about the causes of death in felines constitutes important information to owners, veterinarians, and researchers, aiming at reducing the number of deaths in this species. In order to determine the main causes of death or euthanasia in cats in the Santa Catarina plateau, data from 1995 to 2015 available in necropsy files of the Laboratory of Animal Pathology (LAPA) of the State University of Santa Catarina (UDESC) were collected and evaluated. In that period, 1,728 cats were necropsied, mainly males (46.12%) and adults (50.11%). The mean ages at death for kittens, adults, and elderly were 5.07 months, 3.9 years, and 13.9 years, respectively. Of the 1,728 necropsy reports assessed, the cause of death was identified in 1,184 (68.52%) cases. The main cause of death was associated with infectious diseases (15.8%), with prevalence of feline infectious peritonitis (29.76%), followed by neoplasms (11.98%) with lymphoma (44.93%) and leukemia (16.91%) as the most common, and traumas (11.81%) mainly caused by motor vehicle accidents. These results show the need for owner awareness, as well as establishment of prophylaxis and vaccination programs, aimed at reducing the number of deaths and thus increasing life expectancy in the feline population.(AU)

O conhecimento a respeito da causa mortis em felinos é importante para que se construa um informativo para proprietários, médicos veterinários e pesquisadores, objetivando a redução no número de mortes na espécie. Com o intuito de determinar as principais causas de morte ou eutanásia em felinos domésticos no planalto catarinense foram avaliados os arquivos de registro das necropsias do período de 1995 a 2015 do Laboratório de Patologia Animal da Universidade do Estado de Santa Catarina. No período, foram necropsiados 1.728 felinos, principalmente machos (46,12%), adultos (50,11%). A idade média para filhotes foi de 5,07 meses, enquanto para adultos foi 3,9 anos e para idosos 13,9 anos. Das 1.728 necropsias de felinos, a enfermidade que levou o animal a morte foi determinada em 1.184 (68,52%). As doenças infecciosas foram a principal causa de morte (15,8%), dentre as quais a peritonite infecciosa felina (29,76%) foi a mais frequente; seguida das neoplasias (11,98%), sendo o linfoma (44,93%) e a leucemia (16,91%), as mais comuns; e dos traumatismos (11,81%), principalmente atropelamentos por veículos automotivos. Estes resultados refletem a necessidade da conscientização dos proprietários, bem como da instituição de programas de profilaxia e vacinação, visando a redução de mortes e o aumento na expectativa de vida para a população felina.(AU)

Seroepidemiological study of feline coronavirus (FCoV) infection in domiciled cats from Botucatu, São Paulo, Brazil / Estudo soroepidemiológico da infecção pelo coronavírus felino (FCOV) em gatos domiciliados de Botucatu, São Paulo, Brasil

Feline coronavirus (FCoV) is responsible for causing one of the most important infectious diseases of domestic and wild felids, the feline infectious peritonitis (FIP), which is an immune-mediated, systemic, progressive and fatal disease. FCoV is highly contagious, and infection is common in domestic feline populations worldwide. The present study aimed to determine the seropositivity of FCoV infection and its associated epidemiological variables (risk factors) in domiciled cats in Botucatu, São Paulo, Brazil. Whole blood samples (0.5-1mL) were collected from 151 cats, and sera were extracted by centrifugation. These sera were tested by an commercial enzyme-linked immunosorbent assay (ELISA) for the detection of IgG anti-FCoV antibodies. The assessed risk factors were age range, breed, gender, reproductive status, outdoor access and rearing mode (living alone or in a group). The seropositivity was 64.2% (97/151). There was no statistical significance for risk factors related to breed, gender or rearing mode. There were significant differences in seropositivity (p-values ≤0.05) for age range (p=0.0157), reproductive status (p=0.0074) and outdoor access (p=0.0001). This study verified a wide dissemination of FCoV in the studied population, with a higher than expected seropositivity for indoor cats. Among the risk factors, age range, reproductive status and outdoor access presented statistically significant differences, thus helping to establish an epidemiological profile of this population.(AU)

O coronavírus felino (FCoV) é responsável por causar uma das mais importantes doenças infecciosas que acometem os felinos domésticos e selvagens, a peritonite infecciosa felina (PIF), que é uma enfermidade imunomediada, sistêmica, progressiva e fatal. O FCoV é altamente contagioso e a infecção é comum nas populações de felinos domésticos por todo o mundo. O presente estudo objetivou determinar a soropositividade da infecção pelo FCoV e correlacionar variáveis epidemiológicas (fatores de risco) de gatos domiciliados de Botucatu, São Paulo, Brasil. Amostras de sangue total (0,5 a 1mL) foram colhidas de 151 gatos e os soros foram obtidos após centrifugação. Estes soros foram testados por um teste commercial de ELISA para detecção de anticorpos IgG anti-FCoV. Os fatores de risco avaliados foram faixa etária, raça, gênero, condição reprodutiva, acesso à rua e modo de criação (viver solitário ou em grupo). Observou-se uma soropositividade de 64,2% (97/151). Não houve significância estatística para os fatores de risco relacionados à raça, gênero e modo de criação. Houve significância estatística quanto a soropositividade (p-values ≤0,05) para os fatores de risco faixa etária (p=0,0157), condição reprodutiva (p=0,0074) e acesso à rua (p=0,0001). Através do presente estudo verificou-se que o FCoV está amplamente disseminado na população estudada, onde a soropositividade encontrada foi maior do que a esperada para gatos domiciliados. Dentre os fatores de risco, faixa etária, condição reprodutiva e acesso à rua apresentaram diferenças estatisticamente significativas, contribuindo assim, para se estabelecer um perfil epidemiológico desta população.(AU)

Circulation and genetic diversity of Feline coronavirus type I and II from clinically healthy and FIP-suspected cats in China.

Feline infectious peritonitis (FIP) is a fatal infectious disease of wild and domestic cats, and the occurrence of FIP is frequently reported in China. To trace the evolution of type I and II feline coronavirus in China, 115 samples of ascetic fluid from FIP-suspected cats and 54 fecal samples from clinically healthy cats were collected from veterinary hospitals in China. The presence of FCoV in the samples was detected by RT-PCR targeting the 6b gene. The results revealed that a total of 126 (74.6%, 126/169) samples were positive for FCoV: 75.7% (87/115) of the FIP-suspected samples were positive for FCoV, and 72.2% (39/54) of the clinically healthy samples were positive for FCoV. Of the 126 FCoV-positive samples, 95 partial S genes were successfully sequenced. The partial S gene-based genotyping indicated that type I FCoV and type II FCoV accounted for 95.8% (91/95) and 4.2% (4/95), respectively. The partial S gene-based phylogenetic analyses showed that the 91 type I FCoV strains exhibited genetic diversity; the four type II FCoV strains exhibited a close relationship with type II FCoV strains from Taiwan. Three type I FCoV strains, HLJ/HRB/2016/10, HLJ/HRB/2016/11 and HLJ/HRB/2016/13, formed one potential new clade in the nearly complete genome-based phylogenetic trees. Further analysis revealed that FCoV infection appeared to be significantly correlated with a multi-cat environment (p < 0.01) and with age (p < 0.01). The S gene of the three type I FCoV strains identified in China, BJ/2017/27, BJ/2018/22 and XM/2018/04, exhibited a six nucleotide deletion (C4035 AGCTC4040 ). Our data provide evidence that type I and type II FCoV strains co-circulate in the FIP-affected cats in China. Type I FCoV strains exhibited high prevalence and genetic diversity in both FIP-affected cats and clinically healthy cats, and a multi-cat environment and age (<6 months) were significantly associated with FCoV infection.

Clinical and laboratory features of cats with feline infectious peritonitis--a retrospective study of 231 confirmed cases (2000-2010).

OBJECTIVES: The objectives of this study were to review signalment, clinical signs and laboratory features in a large number of naturally occurring cases of feline infectious peritonitis (FIP), and to evaluate potential changes in diagnostic criteria for FIP and compare findings in cats with and without effusion. METHODS: The medical records of 231 cats with confirmed FIP that presented to the Clinic of Small Animal Medicine of the Ludwig-Maximilian University of Munich, Germany, were reviewed for signalment, history, and clinical and laboratory parameters. Age, sex and breed distribution of the cats were compared with the clinic population. RESULTS: Male sex and young age were significantly correlated with FIP. Neutering status was not associated with FIP. No breed predisposition was observed and the majority of cats presented were domestic shorthair and mixed breed. Microcytosis of peripheral erythrocytes was found in 35.1% of cats, of which 42.4% did not have concurrent anaemia. Band neutrophilia was documented in 44.3% (81/183), of which 35.8% did not have mature neutrophilia. Lymphopenia, observed significantly more often with effusion, was documented in only 26.8% of cats without effusion. Hyperbilirubinaemia also occurred significantly more often in cats with vs without effusion. While serum total protein was increased in only 17.5% of cats, hyperglobulinaemia was documented in 89.1%. Nearly 85.0% of cats had an albumin-to-globulin (A:G) ratio <0.8, while 67.8% had an A:G ratio <0.6. CONCLUSIONS AND RELEVANCE: Microcytosis was common and can increase suspicion of FIP in the presence of other typical clinical and laboratory abnormalities. The low prevalence of lymphopenia in cats without effusion suggests that this is not a useful parameter in non-effusive FIP. The frequent occurrence of a left shift in the absence of a mature neutrophilia complicates the differentiation of effusive FIP and septic peritonitis. Globulins and A:G ratio were of higher diagnostic value than hyperproteinaemia.

Molecular epidemiological study of feline coronavirus strains in Japan using RT-PCR targeting nsp14 gene.

BACKGROUND: Feline infectious peritonitis is a fatal disease of cats caused by infection with feline coronavirus (FCoV). For detecting or genotyping of FCoV, some RT-PCR plus nested PCR techniques have been reported previously. However, referring to the whole genome sequences (WGSs) registered at NCBI, there are no detection methods that can tolerate the genetic diversity among FCoV population. In addition, the quasispecies nature of FCoV, which consists of heterogeneous variants, has been also demonstrated; thus, a universal method for heteropopulations of FCoV variants in clinical specimens is desirable. RESULTS: To develop an RT-PCR method for detection and genotyping of FCoV, we performed comparative genome analysis using WGSs of 32 FCoV, 7 CCoV and 5 TGEV strains obtained from NCBI. As the PCR target, we focused on the nsp14 coding region, which is highly conserved and phylogenetically informative, and developed a PCR method targeting nsp14 partial sequences. Among 103 ascites, 45 pleural effusion and 214 blood specimens from clinically ill cats, we could detect FCoV in 55 (53.4%), 14 (31.1%) and 19 (8.9%) specimens using the present method. Direct sequencing of PCR products and phylogenetic analysis allowed discrimination between type I- and II-FCoV serotypes. Our nsp14 amino acid sequence typing (nsp14 aa ST) showed that the FCoV clone with sequence type (ST) 42, which was the most predominant genotype of WGS strains, was prevalent in domestic cats in Japan. CONCLUSIONS: Our nsp14 PCR scheme will contribute to virus detection, epidemiology and ecology of FCoV strains.

A retrospective clinical and epidemiological study on feline coronavirus (FCoV) in cats in Istanbul, Turkey.

The presence of antibodies to feline coronavirus (FCoV) and feline immunodeficiency virus (FIV), together with feline leukemia virus (FeLV) antigen was investigated in 169 ill household and stray cats attending a veterinary surgery in Istanbul in 2009-14. The estimated FCoV and FIV seroprevalence (95% confidence intervals) were 37% (30-45%) and 11% (6-16%), respectively and FeLV prevalence was 1% (0-3%). FCoV seroprevalence increased until 2 years of age, was highest in 2014 and among household cats living with other cats and with outdoor access, and was lower in FIV seropositive compared to seronegative cats. Symptoms typically associated with wet feline infectious peritonitis (FIP) including ascites, abdominal distention or pleural effusion, coupled in many cases with non-antibiotic responsive fever, were observed in 19% (32/169) of cats, and 75% (24/32) of these cats were FCoV seropositive. FCoV seropositivity was also associated with a high white blood cell count, high plasma globulin, low plasma albumin and low blood urea nitrogen. The percentage of FCoV seropositive and seronegative cats that died in spite of supportive veterinary treatment was 33% (21/63) and 12% (13/106), respectively. These results indicate that FCoV is widespread and has a severe clinical impact in cats from Istanbul. Moreover, the incidence of FCoV infections could be rising, and in the absence of effective vaccination cat owners need to be made aware of ways to minimize the spread of this virus.