Malassezia dermatitis in dogs and cats.

Malassezia are members of the mycobiome of dogs and cats. In the presence of an underlying disease, these yeasts can proliferate, attach to the skin or mucosa to induce a secondary Malassezia dermatitis, otitis externa or paronychia. Since allergic dermatitis is one of the most common underlying causes, diagnostic investigation for allergy is often indicated. Cats may suffer from various other underlying problems, especially where Malassezia dermatitis is generalised. Malassezia dermatitis in dogs and cats is chronic, relapsing and pruritic. Direct cytology from dermatological lesions and the ear canal, showing "peanut-shaped" budding yeasts, facilitates a rapid and reliable diagnosis. Topical treatment includes antiseptic and antifungal azole-based products. Systemic treatment with oral antifungals is indicated only in severe or refractory disease. Identification and treatment of the underlying cause is essential for an optimal response. In this evidence-based narrative review, we discuss the clinical presentation of Malassezia dermatitis in dogs and cats, underlying comorbidities, and diagnostic considerations. Treatment is discussed in light of emerging evidence of antifungal resistance and the authors' clinical experience.

Epidemiology of Pathogenic Retroviruses and Domestic Cat Hepadnavirus in Community and Client-Owned Cats in Hong Kong.

Understanding the local epidemiology of feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) in Hong Kong will inform retrovirus prevention strategies. Domestic cat hepadnavirus (DCH), a novel hepatitis-B-like virus, is commonly detected among client-owned cats in Hong Kong, but community cats have not been studied. The aims of this study were to investigate the frequency and potential risk factors for (i) FeLV and FIV among community and client-owned cats and (ii) perform molecular detection of DCH among community cats in Hong Kong. Blood samples from 713 cats were obtained from client-owned (n = 415, residual diagnostic) and community cats (n = 298, at trap-neuter-return). Point-of-care (POC) testing for FeLV antigen and feline immunodeficiency virus (FIV) anti-p15 and p24 antibodies was performed. FeLV-positive samples were progressed to p27 sandwich enzyme-linked immunosorbent assay. Whole blood DNA was tested with qPCRs for FeLV U3 and gag, and nested PCRs where additional information was required. DCH qPCR was performed on a subset of community cats (n = 193). A single, regressive, FeLV infection was detected in a client-owned cat (1/415 FeLV U3 qPCR positive, 0.2%, 95% CI 0.0-1.3%). Five/415 client-owned cats tested presumably false FeLV-antigen positive (qPCR negative). No markers of FeLV infection were detected in community cats (0/298; 0%). FIV seroprevalence was much higher in community cats (46/298, 15.4%) than in client-owned cats (13/415, 3.1%) (p < 0.001). Mixed breed was a risk factor for FIV infection in client-owned cats. Neither sex nor age were associated with FIV infection. DCH DNA was detected in 34/193 (17.6%) community cats (median viral load 6.32 × 103 copies/reaction). FeLV infection is rare in Hong Kong, negatively impacting the positive predictive value of diagnostic tests. FeLV-antigen testing remains the screening test of choice, but confirmation of a positive result using FeLV qPCR is essential. FIV infection is common in community cats and the absence of a sex predisposition, seen previously in cats managed similarly, raises questions about virus-transmission dynamics in these groups. DCH infection is very common in Hong Kong, both in client-owned and community cats, highlighting the importance of understanding the pathogenic potential of this virus for cats.

Salmonella enterica subspecies enterica serotype Typhimurium induced pyelonephritis and suspected multifocal myositis in a cat.

Case summary: A 2-year-old male neutered domestic shorthair cat presented with an acute onset of muscular pain, ataxia and fever. Serological tests for Toxoplasma gondii IgM and IgG, cryptococcal antigen, feline immune deficiency virus antibody and feline leukaemia virus antigen were all negative. Brain and spinal MRI showed evidence of myositis and bilateral renal parenchymal abnormalities and pyelectasis. Salmonella enterica subspecies enterica serotype Typhimurium 1,4, [5],12:i:1,2 was isolated from urine and was susceptible to amoxycillin, amoxycillin-clavulanic acid, enrofloxacin and trimethoprim-sulfonamide. All clinical signs resolved after a 2-week treatment course with oral amoxycillin-clavulanate. A repeat urine culture 7 days after completing the antimicrobial course was negative. Relevance and novel information: Infection with Salmonella species is uncommon in cats and has not previously been reported in association with pyelonephritis or generalised myositis. The importance of performing urine culture in the initial diagnostic investigation of cats with pyrexia is highlighted in this case report.

Invasive fungal infections and oomycoses in cats 2. Antifungal therapy.

CLINICAL RELEVANCE: Invasive fungal infections (IFIs) and oomycoses (hereafter termed invasive fungal-like infections [IFLIs]) are characterised by penetration of tissues by fungal elements. The environment is the most common reservoir of infection. IFIs and IFLIs can be frustrating to treat because long treatment times are usually required and, even after attaining clinical cure, there may be a risk of relapse. Owner compliance with medication administration and recheck examinations can also decline over time. In addition, some antifungal drugs are expensive, have variable interpatient pharmacokinetic properties, can only be administered parenterally and/or have common adverse effects (AEs). Despite these limitations, treatment can be very rewarding, especially when an otherwise progressive and fatal disease is cured. AIM: In the second of a two-part article series, the spectrum of activity, mechanisms of action, pharmacokinetic and pharmacodynamic properties, and AEs of antifungal drugs are reviewed, and the treatment and prognosis of specific IFIs/IFLIs - dermatophytic pseudomycetoma, cryptococcosis, sino-orbital aspergillosis, coccidioidomycosis, histoplasmosis, sporotrichosis, phaeohyphomycosis, mucormycosis and oomycosis - are discussed. Part 1 reviewed the diagnostic approach to IFIs and IFLIs. EVIDENCE BASE: Information on antifungal drugs is drawn from pharmacokinetic studies in cats. Where such studies have not been performed, data from 'preclinical' animals (non-human studies) and human studies are reviewed. The review also draws on the wider published evidence and the authors' combined expertise in feline medicine, mycology, dermatology, clinical pathology and anatomical pathology. ABBREVIATIONS FOR ANTIFUNGAL DRUGS: AMB (amphotericin B); FC (flucytosine); FCZ (fluconazole); ISA (isavuconazole); ITZ (itraconazole); KCZ (ketoconazole); PCZ (posaconazole); TRB (terbinafine); VCZ (voriconazole).

Invasive Fungal Infections and Oomycoses in Cats: 1. Diagnostic approach.

CLINICAL RELEVANCE: In contrast to superficial fungal infections, such as dermatophytosis, invasive fungal infections (IFIs) are characterised by penetration of tissues by fungal elements. Disease can spread locally within a region or can disseminate haematogenously or via the lymphatics. The environment is the most common reservoir of infection. Since fungal spores are airborne, indoor cats are also susceptible to IFIs. Some environmental fungi are ubiquitous and present globally, while others are endemic or hyperendemic within specific geographic regions. Zoonotic pathogens include Microsporum canis, Sporothrix schenckii and Sporothrix brasiliensis. AIM: In the first of a two-part article series, the approach to the investigation of feline IFIs and oomycoses is reviewed. As well as tips for diagnosis, and information on the ecological niche and distribution of fungal pathogens, the review covers clinical presentation of the most common IFIs, including cryptococcosis, histoplasmosis, blastomycosis, coccidioidomycosis, sporotrichosis, phaeohyphomycosis, aspergillosis and dermatophytic pseudomycetoma, as well as the oomycoses pythiosis, lagenidiosis and paralagenidiosis. In Part 2, the spectrum of activity, mechanisms of action, pharmacokinetic and pharmacodynamic properties and adverse effects of antifungal drugs are reviewed, and the treatment and prognosis for specific IFIs and oomycoses are discussed. EVIDENCE BASE: The review draws on published evidence and the authors' combined expertise in feline medicine, mycology, dermatology, clinical pathology and anatomical pathology.

Reply to Piewbang et al. Domestic Cat Hepadnavirus Antigens in Lymphoma Tissues. Comment on "Beatty et al. Domestic Cat Hepadnavirus and Lymphoma. Viruses 2023, 15, 2294".

We are grateful to the authors for providing additional data to demonstrate the presence of domestic cat hepadnavirus in lymphoma tissues [...].

Domestic Cat Hepadnavirus and Lymphoma.

We write to comment on Piewbang C et al [...].

Babesia gibsoni Infection in a Cat with Immune-Mediated Haemolytic Anaemia and Thrombocytopenia.

Tick-borne haemoparasite Babesia gibsoni has been detected rarely in cats, in surveys of apparently healthy animals. In stored blood from a 6-year-old male-neutered domestic shorthair cat in Hong Kong, B. gibsoni DNA was detected retrospectively using PCR for Babesia spp. 18S rRNA and mitochondrial cytochrome B genes, followed by sequencing and basic local alignment search tool (BLAST) analysis. The cat presented with severe haemolytic anaemia and thrombocytopenia. The cat responded to supportive care and glucocorticoids and was clinically normal despite persistent subclinical thrombocytopenia until six months after presentation, when it succumbed to a fatal haemorrhagic episode. Necropsy revealed severe intestinal and pulmonary haemorrhage and hypocellular bone marrow with megakaryocytosis but no other causes of immune-mediated thrombocytopenia (IMTP) or immune-mediated haemolytic anaemia (IMHA). Blood stored on days 158 and 180 tested PCR negative for Babesia spp. This report demonstrates that geographic range of B. gibsoni detection in cats includes Hong Kong. The exclusion of other causes suggests that B. gibsoni might have potentially played a role in triggering immune-mediated disease in this case.

Dermatological Problems of Brachycephalic Dogs.

Brachycephalic dogs are not only affected by brachycephalic obstructive airway syndrome (BOAS), but are also frequently referred to veterinary dermatologists for skin conditions, with English bulldogs and pugs particularly over-represented. Some skin diseases, such as skin fold dermatitis, are directly associated with the abnormal anatomic conformation of brachycephalic dogs, while for others, such as atopic dermatitis and viral pigmented plaques, there is an underlying genetic basis or a general predisposition. Anatomic alterations associated with brachycephaly, leading to fold formation of the skin and stenosis of the ear canal, together with primary immunodeficiencies described in some breeds, favor the development of pyoderma, Malassezia dermatitis, and otitis externa/media. In addition, the frequently neglected but often lifelong dermatological problems of brachycephalic dogs are an important consideration when discussing genetic and medical conditions affecting the welfare of those dogs. Here we review the current state of knowledge concerning dermatological problems in brachycephalic dogs and combine it with clinical experience in the management of these challenging disorders.

Prevalence of Babesia and Ehrlichia in owned dogs with suspected tick-borne infection in Hong Kong, and risk factors associated with Babesia gibsoni.

Babesiosis and ehrlichiosis are the most clinically significant tick-borne infections in dogs. Although epidemiological investigations of these diseases have been performed in some Asian regions, little data is available in Hong Kong, where competent vector tick species are endemic. The objectives of this study were to determine the molecular prevalence of Ehrlichia canis and Babesia species (B. canis, B. gibsoni, B. vogeli) in owned dogs suspected of tick-borne infection in Hong Kong and to identify risk factors associated with B. gibsoni infection. Electronic records from the Veterinary Diagnostic Laboratory of City University of Hong Kong were searched to identify canine blood samples submitted for molecular testing of these pathogens by real time PCR between March 2018 and May 2021. Electronic patient records from the affiliated veterinary hospital were searched to identify a subset of tested dogs to investigate the potential risk factors for B. gibsoni infection using logistic regression models. Among 1508 tested dogs for all four pathogens of interest, Babesia spp. were detected in 435 (28.8%) and E. canis in 112 (7.4%). Babesia gibsoni was detected in 408 dogs while B. vogeli was detected in 27 dogs. Babesia canis was not detected in any dog. Co-infections of different combinations of B. gibsoni, B. vogeli and E. canis were present in 25 dogs. In multivariable logistic regression, mixed breed dogs were more likely to be infected with B. gibsoni than purebreds (P = 0.005), while dogs > 10 years of age were less likely to be infected than younger dogs (P = 0.019). Hematological abnormalities significantly associated with B. gibsoni infection included thrombocytopenia, neutropenia, or pancytopenia. Babesiosis caused by B. gibsoni is a common infection in owned dogs suspected of tick-borne infection in Hong Kong. The risk factors reported should be considered in diagnosing dogs suspected of infection with this agent. Furthermore, consideration for testing for B. gibsoni infection should be given if the results of a complete blood count show thrombocytopenia even in the absence of anemia, neutropenia or pancytopenia.

Low Prevalence of SARS-CoV-2 Antibodies in Canine and Feline Serum Samples Collected during the COVID-19 Pandemic in Hong Kong and Korea.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people worldwide since its emergence in 2019. Knowing the potential capacity of the virus to adapt to other species, the serological surveillance of SARS-CoV-2 infection in susceptible animals is important. Hong Kong and Seoul are two of Asia's most densely populated urban cities, where companion animals often live in close contact with humans. Sera collected from 1040 cats and 855 dogs during the early phase of the pandemic in Hong Kong and Seoul were tested for SARS-CoV-2 antibodies using an ELISA that detects antibodies against the receptor binding domain of the viral spike protein. Positive sera were also tested for virus neutralizing antibodies using a surrogate virus neutralization (sVNT) and plaque reduction neutralization test (PRNT). Among feline sera, 4.51% and 2.54% of the samples from Korea and Hong Kong, respectively, tested ELISA positive. However, only 1.64% of the samples from Korea and 0.18% from Hong Kong tested positive by sVNT, while only 0.41% of samples from Korea tested positive by PRNT. Among canine samples, 4.94% and 6.46% from Korea and Hong Kong, respectively, tested positive by ELISA, while only 0.29% of sera from Korea were positive on sVNT and no canine sera tested positive by PRNT. These results confirm a low seroprevalence of SARS-CoV-2 exposure in companion animals in Korea and Hong Kong. The discordance between the RBD-ELISA and neutralization tests may indicate possible ELISA cross-reactivity with other coronaviruses, especially in canine sera.

Domestic Cat Hepadnavirus: Molecular Epidemiology and Phylogeny in Cats in Hong Kong.

Domestic cat hepadnavirus (DCH) is an emerging virus related to the hepatitis B virus (HBV). The pathogenic potential of DCH in cats remains to be established. The molecular prevalence of DCH varies widely in the regions investigated so far. The aim of this study was to determine the prevalence, load, and risk factors for DCH detection among cats in Hong Kong, and to generate molecular and epidemiological data on the DCH strains circulating in cats in Hong Kong. DCH DNA was detected using DCH-specific qPCR in 57/513 (11.1%) residual diagnostic blood samples from owned cats. The median viral load was 8.85 × 103 copies/mL of whole blood (range for the 5th to the 95th percentile, 3.33 × 103 to 2.2 × 105 copies per mL). Two outliers had higher viral loads of 1.88 × 107 copies/mL and 4.90 × 109 copies/mL. DCH was detected in cats from 3 months to 19 years of age. Sex, age, neuter status, breed, or elevated serum alanine aminotransferase were not statistically associated with DCH DNA detection. On phylogenetic analysis based on 12 complete genome sequences, the Hong Kong DCH viruses clustered in Genotype A with viruses from Australia and Asia (clade A1), distinct from viruses from Europe (clade A2). Sequence analysis found that DCH has similar epsilon and direct repeat regions to human HBV, suggesting a conserved method of replication. Based on our findings, the DCH strains circulating in Hong Kong are a continuum of the Asiatic strains.

Domestic Cat Hepadnavirus and Pathogenic Retroviruses; A Sero-Molecular Survey of Cats in Santiago, Chile.

Cat ownership is common in Chile, but data on the regional prevalence of infectious agents are limited. A sero-molecular survey of 120 client- or shelter-owned domestic cats in greater Santiago was performed. Whole blood DNA was tested for the novel hepatitis-B-like virus, domestic cat hepadnavirus (DCH) by conventional PCR (cPCR) and quantitative PCR (qPCR), and for feline leukaemia virus (FeLV) by qPCR. Point-of-care serology for FeLV p27 antigen and antibodies recognising feline immunodeficiency virus (FIV) p15 and p24 was performed. DCH DNA was detected in the serum of 2/120 cats (1.67%). Sequencing and phylogenetic analysis showed that the DCH detected in Chile occupies a position outside the main clustering of DCH in the near-complete genome tree. Progressive (antigen-positive, provirus-positive) and regressive (antigen-negative, provirus-positive) FeLV infections were identified in 6/120 (5%) and 9/120 (7.5%) of cats. A total of 2/120 (1.7%) cats had dual FeLV/FIV infection, and another 2 cats had FIV infection alone. This study shows that the global footprint of DCH includes South America with a low molecular frequency in Chile, similar to that reported in the USA. Progressive FeLV infection is relatively common in urban Chile, and male cats are at greater risk than females. Testing and control measures for pathogenic retroviruses are indicated. The potential impact of FeLV, FIV and DCH on Chile's wildcat species is worthy of further investigation.

Brachycephalic obstructive airway syndrome: much more than a surgical problem.

Brachycephalic obstructive airway syndrome (BOAS) is a chronic, lifelong, debilitating, primarily obstructive airway disease which adversely affects the quality of life of many popular dog breeds. Respiratory restriction in bulldog breeds, pugs and Boston terriers frequently co-exist with pathologies of the gastrointestinal tract. In addition, many brachycephalic dogs that appear clinically normal are, in fact suffering from chronic hypoxia and its systemic consequences. Concurrent gastroesophageal reflux-associated conditions, sleep disorders and systemic hypertension further impact the welfare of affected dogs. Acceptance of BOAS and associated clinical signs as being 'normal for the breed' is common amongst owners. While surgical correction of the upper airway is the mainstay of treatment, the provision of subsequent, frequently lifelong medical management is equally important for the maintenance of an acceptable quality of life, at least for some affected patients. Here we review the current knowledge concerning brachycephaly, combine it with shared clinical experience in the management of this debilitating condition, and discuss ethical considerations and the responsibility of veterinarians to contribute public education and to support appropriate breed standards for animals under our care.

Faecal virome of the Australian grey-headed flying fox from urban/suburban environments contains novel coronaviruses, retroviruses and sapoviruses.

Bats are important reservoirs for viruses of public health and veterinary concern. Virus studies in Australian bats usually target the families Paramyxoviridae, Coronaviridae and Rhabdoviridae, with little known about their overall virome composition. We used metatranscriptomic sequencing to characterise the faecal virome of grey-headed flying foxes from three colonies in urban/suburban locations from two Australian states. We identified viruses from three mammalian-infecting (Coronaviridae, Caliciviridae, Retroviridae) and one possible mammalian-infecting (Birnaviridae) family. Of particular interest were a novel bat betacoronavirus (subgenus Nobecovirus) and a novel bat sapovirus (Caliciviridae), the first identified in Australian bats, as well as a potentially exogenous retrovirus. The novel betacoronavirus was detected in two sampling locations 1375 km apart and falls in a viral lineage likely with a long association with bats. This study highlights the utility of unbiased sequencing of faecal samples for identifying novel viruses and revealing broad-scale patterns of virus ecology and evolution.

Malassezia: Zoonotic Implications, Parallels and Differences in Colonization and Disease in Humans and Animals.

Malassezia spp. are commensals of the skin, oral/sinonasal cavity, lower respiratory and gastrointestinal tract. Eighteen species have been recovered from humans, other mammals and birds. They can also be isolated from diverse environments, suggesting an evolutionary trajectory of adaption from an ecological niche in plants and soil to the mucocutaneous ecosystem of warm-blooded vertebrates. In humans, dogs and cats, Malassezia-associated dermatological conditions share some commonalities. Otomycosis is common in companion animals but is rare in humans. Systemic infections, which are increasingly reported in humans, have yet to be recognized in animals. Malassezia species have also been identified as pathogenetic contributors to some chronic human diseases. While Malassezia species are host-adapted, some species are zoophilic and can cause fungemia, with outbreaks in neonatal intensive care wards associated with temporary colonization of healthcare worker's hands from contact with their pets. Although standardization is lacking, susceptibility testing is usually performed using a modified broth microdilution method. Antifungal susceptibility can vary depending on Malassezia species, body location, infection type, disease duration, presence of co-morbidities and immunosuppression. Antifungal resistance mechanisms include biofilm formation, mutations or overexpression of ERG11, overexpression of efflux pumps and gene rearrangements or overexpression in chromosome 4.

Low Intrahost and Interhost Genetic Diversity of Carnivore Protoparvovirus 1 in Domestic Cats during a Feline Panleukopenia Outbreak.

Feline panleukopenia (FPL), a highly contagious and frequently fatal disease of cats, is caused by Feline parvovirus (FPV) and Canine parvovirus (CPV). We characterised the diversity of these Carnivore protoparvovirus 1 variants in 18 faecal samples collected from domestic cats with FPL during an outbreak, using targeted parvoviral DNA metagenomics to a mean depth of >10,000 × coverage per site. All samples comprised FPV alone. Compared with the reference FPV genome, isolated in 1967, 44 mutations were detected. Ten of these were nonsynonymous, including 9 in nonstructural genes and one in VP1/VP2 (Val232Ile), which was the only one to exhibit interhost diversity, being present in five sequences. There were five other polymorphic nucleotide positions, all with synonymous mutations. Intrahost diversity at all polymorphic positions was low, with subconsensus variant frequencies (SVF) of <1% except for two positions (2108 and 3208) in two samples with SVF of 1.1−1.3%. Intrahost nucleotide diversity was measured across the whole genome (0.7−1.5%) and for each gene and was highest in the NS2 gene of four samples (1.2−1.9%). Overall, intrahost viral genetic diversity was limited and most mutations observed were synonymous, indicative of a low background mutation rate and strong selective constraints.

Hepadnavirus DNA Is Detected in Canine Blood Samples in Hong Kong but Not in Liver Biopsies of Chronic Hepatitis or Hepatocellular Carcinoma.

Chronic hepatitis and hepatocellular carcinoma (HCC) caused by the hepadnavirus hepatitis B virus (HBV) are significant causes of human mortality. A hepatitis-B-like virus infecting cats, domestic cat hepadnavirus (DCH), was reported in 2018. DCH DNA is hepatotropic and detectable in feline blood or serum (3.2 to 12.3%). Detection of HBV DNA has been reported in sera from 10% of free-roaming dogs in Brazil, whereas 6.3% of sera from dogs in Italy tested positive for DCH DNA by real-time quantitative PCR (qPCR). If DCH, HBV, or another hepadnavirus is hepatotropic in dogs, a role for such a virus in the etiology of canine idiopathic chronic hepatitis (CH) or HCC warrants investigation. This study investigated whether DCH DNA could be detected via qPCR in blood from dogs in Hong Kong and also whether liver biopsies from dogs with confirmed idiopathic CH or HCC contained hepadnaviral DNA using two panhepadnavirus conventional PCRs (cPCR) and a DCH-specific cPCR. DCH DNA was amplified from 2 of 501 (0.4%) canine whole-blood DNA samples. A second sample taken 6 or 7 months later from each dog tested negative in DCH qPCR. DNA extracted from 101 liver biopsies from dogs in Hong Kong or the USA, diagnosed by board-certified pathologists as idiopathic CH (n = 47) or HCC (n = 54), tested negative for DCH DNA and also tested negative using panhepadnavirus cPCRs. This study confirms that DCH DNA can be detected in canine blood by qPCR, although at a much lower prevalence than that reported previously. We identified no evidence to support a pathogenic role for a hepadnavirus in canine idiopathic CH or HCC.

The enteric virome of cats with feline panleukopenia differs in abundance and diversity from healthy cats.

Feline panleukopenia (FPL) is a severe, often fatal disease caused by feline panleukopenia virus (FPV). How infection with FPV might impact the composition of the entire eukaryotic enteric virome in cats has not been characterized. We used meta-transcriptomic and viral particle enrichment metagenomic approaches to characterize the enteric viromes of 23 cats naturally infected with FPV (FPV-cases) and 36 age-matched healthy shelter cats (healthy controls). Sequencing reads from mammalian infecting viral families largely belonged to the Coronaviridae, Parvoviridae and Astroviridae. The most abundant viruses among the healthy control cats were feline coronavirus, Mamastrovirus 2 and Carnivore bocaparvovirus 3 (feline bocavirus), with frequent coinfections of all three. Feline chaphamaparvovirus was only detected in healthy controls (6 out of 36, 16.7%). Among the FPV-cases, in addition to FPV, the most abundant viruses were Mamastrovirus 2, feline coronavirus and C. bocaparvovirus 4 (feline bocaparvovirus 2). The latter and feline bocaparvovirus 3 were detected significantly more frequently in FPV-cases than in healthy controls. Feline calicivirus was present in a higher proportion of FPV-cases (11 out of 23, 47.8%) compared to healthy controls (5 out of 36, 13.9%, p = 0.0067). Feline kobuvirus infections were also common among FPV-cases (9 out of 23, 39.1%) and were not detected in any healthy controls (p < .0001). While abundant in both groups, astroviruses were more frequently present in FPV-cases (19 out of 23, 82.6%) than in healthy controls (18 out of 36, p = .0142). The differences in eukaryotic virome composition revealed here indicate that further investigations are warranted to determine associations between enteric viral co-infections on clinical disease severity in cats with FPL.