Feline Isolates Research Articles

Diagnostic ultrasonography and antimicrobial resistance of different pathogens associated with canine and feline lower urinary tract disorders

There is a significant issue concerning the dissemination of antimicrobial-resistant bacteria within companion animals. Urinary tract infections (UTIs) are a common problem in veterinary medicine for which empirical antibiotics are utilized. This study aimed to investigate the antimicrobial resistance of different uropathogens associated with UTIs in canine and feline cases. A total of 146 dogs and 162 cats suffered from lower urinary tract disorders were subjected to ultrasonographic and microbiological examination. Cystitis, urinary sediment, and cystic calculi are the most common ultrasonographic abnormalities associated with bacterial UTIs. Bacterial UTIs were obtained in 36.98 % and 25.92 % of cases in dogs and cats, respectively. A low rate of mixed infection was detected in canine cases (3.7 %). E. coli was the most prevalent pathogen isolated from 46.4 % and 66.7 % of canine and feline isolates, respectively followed by Proteus spp. in canine isolates (16.1 %) and Klebsiella spp. in feline isolates (14.3 %). Staphylococcus spp. was isolated from canine cases only with the detection of methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains at 3.6 %. The majority of the isolated strains were resistant to various antibiotic classes, particularly β-lactams. All gram-negative bacteria were susceptible to amikacin, whereas gram-positive strains exhibited 100 % sensitivity to nitrofurantoin and linezolid. Different bacterial species displayed low resistance to carbapenems and fluoroquinolones. Multi-drug resistance was reported in canine and feline strains at 64.3 % and 54.8 %, respectively. These findings prove the crucial necessity to restrict antibiotic consumption depending on urine culture and antibiotic sensitivity tests.

Unveiling genome plasticity and a novel phage in Mycoplasma felis: Genomic investigations of four feline isolates.

Mycoplasma felis has been isolated from diseased cats and horses, but to date only a single fully assembled genome of this species, of an isolate from a horse, has been characterized. This study aimed to characterize and compare the completely assembled genomes of four clinical isolates of M. felis from three domestic cats, assembled with the aid of short- and long-read sequencing methods. The completed genomes encoded a median of 759 ORFs (range 743-777) and had a median average nucleotide identity of 98.2 % with the genome of the available equid origin reference strain. Comparative genomic analysis revealed the occurrence of multiple horizontal gene transfer events and significant genome reassortment. This had resulted in the acquisition or loss of numerous genes within the Australian felid isolate genomes, encoding putative proteins involved in DNA transfer, metabolism, DNA replication, host cell interaction and restriction modification systems. Additionally, a novel mycoplasma phage was detected in one Australian felid M. felis isolate by genomic analysis and visualized using cryo-transmission electron microscopy. This study has highlighted the complex genomic dynamics in different host environments. Furthermore, the sequences obtained in this work will enable the development of new diagnostic tools, and identification of future infection control and treatment options for the respiratory disease complex in cats.

Colonization of methicillin-resistant Staphylococcus species in healthy and sick pets: prevalence and risk factors

BackgroundThe characterization of staphylococcal species that colonize pets is important to maintain animal health and to minimize the risk of transmission to owners. Here, the prevalence of Staphylococcus spp. and methicillin resistance was investigated in canine and feline isolates, and risk factors of staphylococcal colonization were determined. Pets were examined and separated into four groups: (1) healthy dogs, (2) healthy cats, and (3) dogs and (4) cats with clinical signs of bacterial infections of skin, mucous membranes, or wounds. Specimens were collected by a veterinary physician from six anatomic sites (external ear canal, conjunctival sacs, nares, mouth, skin [groin], and anus). In total, 274 animals (cats n = 161, dogs n = 113) were enrolled.ResultsStaphylococcus species were highly diverse (23 species; 3 coagulase-positive and 20 coagulase-negative species), with the highest variety in healthy cats (19 species). The most frequent feline isolates were S. felis and S. epidermidis, while S. pseudintermedius was the most prevalent isolate in dogs. Risk factors of staphylococcal colonization included the presence of other animals in the same household, medical treatment within the last year, and a medical profession of at least one owner. Methicillin resistance was higher in coagulase-negative (17.86%) compared to coagulase-positive (1.95%) staphylococci. The highest prevalence of methicillin-resistant CoNS colonization was observed in animals kept in homes as the most common (dogs and cats).ConclusionsThe association of methicillin-resistant CoNS colonization with animals most often chosen as pets, represents a high risk of transmission between them and owners. The importance of nosocomial transmission of CoNS was also confirmed. This information could guide clinical decisions during the treatment of veterinary bacterial infections. In conclusion, the epidemiologic characteristics of CoNS and their pathogenicity in pets and humans require further research.

Comparative Genomic Analysis and Species Delimitation: A Case for Two Species in the Zoonotic Cestode Dipylidium caninum.

Dipylidium caninum (Linnaeus, 1758) is a common zoonotic cestode of dogs and cats worldwide. Previous studies have demonstrated the existence of largely host-associated canine and feline genotypes based on infection studies, differences at the 28S rDNA gene, and complete mitochondrial genomes. There have been no comparative genome-wide studies. Here, we sequenced the genomes of a dog and cat isolate of Dipylidium caninum from the United States using the Illumina platform at mean coverage depths of 45× and 26× and conducted comparative analyses with the reference draft genome. Complete mitochondrial genomes were used to confirm the genotypes of the isolates. Genomes of D. caninum canine and feline genotypes generated in this study, had an average identity of 98% and 89%, respectively, when compared to the reference genome. SNPs were 20 times higher in the feline isolate. Comparison and species delimitation using universally conserved orthologs and protein-coding mitochondrial genes revealed that the canine and feline isolates are different species. Data from this study build a base for future integrative taxonomy. Further genomic studies from geographically diverse populations are necessary to understand implications for taxonomy, epidemiology, veterinary clinical medicine, and anthelmintic resistance.

Genotyping and antifungal susceptibility testing of Sporothrix brasiliensis isolates from Southern Brazil

Sporotrichosis is an implantation mycosis caused by the dimorphic fungus Sporothrix and mostly involves cutaneous and subcutaneous tissues and the lymphatic vessels. Among more than 50 different species, only Sporothrix schenckii, Sporothrix globosa and Sporothrix brasiliensis are frequently reported to cause infections in humans. Sporothrix brasiliensis is remarkably virulent and has been spreading rapidly in Brazil and other Latin American countries. In this study, we aimed to determine the genetic relatedness and antifungal susceptibility of Sporothrix strains by analysing 89 isolates from humans and cats in Curitiba, Southern Brazil. Calmodulin sequencing identified 81 S. brasiliensis and seven S. schenckii isolates. Amplified fragment length polymorphism genotyping analysis showed feline and human isolates clustering together. In vitro susceptibility testing with seven antifungals demonstrated a broad activity against all tested S. brasiliensis isolates, with no significant differences in minimal inhibitory concentration (MIC) values between feline and human isolates. Resistance was solely observed in one human isolate against itraconazole and posaconazole, with MICs of ≥16 μg/mL against both antifungals. Whole genome sequencing (WGS) analysis on this isolate and two related susceptible isolates did not reveal any unique substitutions in resistance-associated genes, including cyp51, hmg and erg6, when compared to two related susceptible isolates. The novel antifungal olorofim exhibited excellent activity against this large isolate collection, with all isolates considered as susceptible. Altogether, we indicate zoonotic transmission based on genotyping and revealed a broad activity of seven common antifungals, including olorofim, against a large S. brasiliensis isolate collection.

Are γ-terpinene, 1,8-cineole, p-coumaric acid, and quercetin active against wild-type and non-wild-type Sporothrix brasiliensis to itraconazole?

The emergence of itraconazole (ITZ)-resistant Sporothrix brasiliensis in feline and canine cases in southern Brazil has hampered the clinical cure of animal sporotrichosis, encouraging the search for therapeutic alternatives. The promising use of plants extracts from Lamiaceae family is known; however, there are no studies with its major compounds, as γ-terpinene (γTER), 1,8-cineole (1,8CIN), p-coumaric acid (pCOU), and quercetin (QUER). For the first time, we evaluated the antifungal, synergistic, cytotoxic activities and action mechanism of these compounds against S. brasiliensis. For this, 28 S. brasiliensis from cats (n = 24) and dogs (n = 4) and standard strains of S. brasiliensis and S. schenckii (n = 4) were tested by M38-A2 (CLSI), revealing non-wild-type (WT) isolates to ITZ on 54.2% (13/24) and 75% (03/04) of feline and canine isolates, respectively. Of the compounds, γTER stood out against all isolates (MIC/MFC 0.75 to > 3mg/ml; MIC50 3mg/ml). However, 1,8CIN, pCOU, and QUER showed little or no activity (MIC50 > 3mg/ml). Thus, γTER was selected for checkerboard assay, whose combination with ITZ showed synergistic (WT isolates) and indifferent (non-WT isolates) interaction. For action mechanism (sorbitol protection and ergosterol effect), γTER acted in membrane by complexing with fungal ergosterol and at the cell wall level, showing two possible pathways as antifungal target. Finally, cytotoxicity (MTT assay) showed that γTER was the safest compound on MDBK cells, even at a concentration of 3mg/ml (90.16%). Our findings support that γTER is a potent antifungal candidate for the control of sporotrichosis, including against non-WT S. brasiliensis.

Feline sporotrichosis caused by Sporothrix schenckii sensu stricto in Southern Thailand: phenotypic characterization, molecular identification, and antifungal susceptibility.

Feline sporotrichosis caused by the Sporothrix schenckii complex is a global subcutaneous mycosis, having higher prevalence in Latin America and Malaysia. However, its etiological agents have not been elucidated in Thailand, a neighboring country of Malaysia, where the cases are increasing. This study identified 38 feline isolates of S. schenckii from Southern Thailand, collected between 2018 and 2021, using phenotypic characterization and molecular identification using polymerase chain reaction (PCR)-sequencing of partial calmodulin (CAL) and ß-tubulin (Bt2) genes. Phenotypic characteristics proved that the isolates were S. schenckii sensu lato, with low thermotolerance. Based on partial CAL and Bt2-PCR sequencing, all isolates were identified as S. schenckii sensu stricto. Phylogenetic analyses revealed that the isolates were clustered with S. schenckii sensu stricto isolated from the cats in Malaysia. A low degree of genetic diversity was observed among the Thai feline isolates. The antifungal susceptibility of these isolates to antifungal agents, including itraconazole (ITC), ketoconazole (KTC), fluconazole (FLC), and amphotericin B (AMB), was investigated according to the M27-A3 protocol of the Clinical and Laboratory Standards Institute. Results showed low ITC, KTC, and AMB activities against S. schenckii sensu stricto isolates, with high minimum inhibitory concentration (MIC) ranges of 1-8, 1-8, and 2-16μg/ml, respectively, whereas FLC exhibited MICs of 64 and>64μg/ml. This study indicated that S. schenckii sensu stricto is the causative agent responsible for feline sporotrichosis in Southern Thailand. Their phenotypic characteristics and in vitro antifungal susceptibility profiles will help to improve our understanding of this mycosis in Thailand.

In-depth comparative analysis of Tritrichomonas foetus transcriptomics reveals novel genes linked with adaptation to feline host

Tritrichomonas foetus is a flagellated parasite able to infect cattle, cats, and pigs. Despite its prevalence, feline tritrichomonosis has received markedly less attention than venereal infection, and little information about the molecular mechanisms that participate in feline host infection is available. Through a bioinformatics approach, we integrated public transcriptomic data for three T. foetus isolates and explored the differences at transcript level with a focus on pathogenesis and adaptation processes, particularly for the feline isolate. Our analysis revealed higher abundance levels of predicted virulence factors, such as proteases and surface antigens. Additionally, by a comparative and expression analysis of T. foetus genes, we proposed putative virulence factors that could be involved in feline infection. Finally, we identified a great proportion of predicted transcription factors of the MYB protein family and, by a promoter analysis, we revealed that MYB-related proteins could participate in the regulation of gene transcription in T. foetus. In conclusion, this integrated approach is a valuable resource for future studies of host–pathogen interactions and identifying new gene targets for improved feline tritrichomonosis diagnosis and treatment.

Effect of Tritrichomonas foetus, Tf-31 (a cattle isolate) and Tff6 (a feline isolate) on TLR signaling pathway in cervical epithelial cells.

Abstract Bovine trichomonosis is caused by Tritrichomonas foetus, which is widely prevalent in 33 US states, and is a reportable disease due to potential huge economic losses to cattle industry. T. foetus also causes chronic large-bowel diarrhoea in cats, complicated not only by its chronicity but for its difficulty to treat, with few registered or effective products available. T. foetus persistently colonize the lower genital tract of bulls but usually do not cause either major clinical signs or inflammation while vaginal inflammation is a common disease of the dairy cows’ reproductive tract. Mechanisms of immune response to this pathogen are poorly studied. This study for the first time, reports the effect of T. foetus; Tf-31-cattle isolate and Tff6-cat isolate, on activation of toll-like receptors (TLRs) and inflammatory response in vaginal epithelial cells. The expression levels of serial effectors related to the TLRs-MyD88/NF-κB signaling pathway (TLR2, TLR4, MyD88, NF-κB, IL-1β, IL-6, TNF-α, and IL-10) were measured with real-time polymerase chain reaction (RT-PCR), ELISA, and Western blot analyses. Of the 6 cell-membrane TLRs tested, TLR2 and TLR4 were activated by cells, as noted by increased mRNA expression levels of TLR2 and TLR4 in both Tf31 and Tff6 treated cervical epithelial cells relative to control cells. ELISA assays showed up-regulation on IL-10, both in Tf-31 and Tff6 treated epithelial cells. Treatment with inhibitors of MyD88 signaling pathway abolished the upregulation of downstream cytokines. These data indicate that T. foetus isolates activate TLR-MyD88 signaling pathway to induce innate immune response. However, further detailed in vitro and in vivo studies are required to confirm these findings. Supported by Biology department

Bioisosteric modification on benzylidene-carbonyl compounds improved the drug-likeness and maintained the antifungal activity against Sporothrix brasiliensis.

Considering the emergence of antifungal resistance on Sporothrix brasiliensis, we aimed to assess new benzylidene-carbonyl compounds against feline-borne S. brasiliensis isolates. The compounds were designed as bioisosteres from previously reported benzylidene-ketones generating the p-coumaric (1), cinnamic (2), p-methoxycinnamic (3) and caffeic acid (4) analogues. The corresponding compounds were tested against feline isolates of S. brasiliensis with sensitivity (n=4) and resistance (n=5) to itraconazole (ITZ), following the M38-A2 protocol (CLSI, Reference method for broth dilution antifungal susceptibility testing of filamentous fungi M38-A2 Guideline, 2008). Eleven analogues showed activity against all fungal strains with minimum inhibitory concentrations (MIC) ≤1mg/ml (1a-d, 2e, 3b, 3e, 4, 4a and 5e) and fungicidal concentrations (MFC) ≤1mg/ml (1b, 1d, 3e and 4a), whereas 3 was the less active with both MIC and MFC values above 1mg/ml. Compound 3e (4-methoxy-N-butylcinnamamide) was the most potent (MICrange 0.08-0.16mg/ml; MFCrange 0.32-0.64mg/ml) from the set, suggesting a different role of the substituents in ester and amide derivatives. The designed compounds proved to be important prototypes with improved drug-likeness to achieve compounds with higher activity against ITZ-resistant S. brasiliensis.

Results of urinary bacterial cultures and antibiotic susceptibility testing of dogs and cats in the UK.

ObjectivesBacterial urinary tract infections are a common diagnosis in small animal practice and antibiotics are often administered empirically. The aim of this study was to investigate the aetiology and antibiotic resistance of uropathogens in dogs and cats in the UK.Materials and MethodsRetrospective study of uroculture and antibiotic susceptibility testing results (n=808) by disk diffusion processed at a veterinary pathology laboratory between 2011 and 2012.ResultsSignificant bacteriuria was detected in 18.4% of samples from dogs and 10.0% from cats, most of which (>90%) yielded a single organism. Escherichia coli was the most prevalent bacterial species (54.7% and 55.6% of feline and canine isolates, respectively) followed by Proteus mirabilis in dog samples (22.7%) and Enterococcus spp. in cat samples (23.2%). Approximately a third of E. coli isolates were resistant to ampicillin but resistance was much lower among Enterococcus spp. and P. mirabilis. Resistance to amoxicillin‐clavulanic acid also seemed to be emerging, particularly in E. coli (almost 20% resistant). In contrast, resistance to trimethoprim‐sulfamethoxazole for uropathogens remained <13% except for P. mirabilis (19.4%). Overall, fluoroquinolones showed the best in vitro activity (resistance mostly below 10% for enrofloxacin and marbofloxacin).Clinical SignificanceOur results provide evidence of the emergence of resistance to antibiotics commonly used to treat bacterial urinary tract infections. Continued monitoring of the patterns of antibiotic resistance in uropathogens is needed to assess the adequacy of recommendations on the empiric therapy of these infections.

S. pseudintermedius and S. aureus lineages with transmission ability circulate as causative agents of infections in pets for years

BackgroundStaphylococcus pseudintermedius (SP) and Staphylococcus aureus (SA) are common colonizers of companion animals, but they are also considered opportunistic pathogens, causing diseases of diverse severity. This study focused on the identification and characterization of 33 coagulase-positive staphylococci isolated from diseased pets (28 dogs and five cats) during 2009–2011 in a veterinary hospital in Spain in order to stablish the circulating lineages and their antimicrobial resistance profile.ResultsTwenty-eight isolates were identified as SP and five as SA. Nine methicillin-resistant (MR) isolates (27%) carrying the mecA gene were detected (eight MRSP and one MRSA). The 55% of SP and SA isolates were multidrug-resistant (MDR). MRSP strains were typed as ST71-agrIII-SCCmecII/III-(PFGE) A (n=5), ST68-agrIV-SCCmecV-B1/B2 (n=2), and ST258-agrII-SCCmecIV-C (n=1). SP isolates showed resistance to the following antimicrobials [percentage of resistant isolates/resistance genes]: penicillin [82/blaZ], oxacillin [29/mecA] erythromycin/clindamycin [43/erm(B)], aminoglycosides [18–46/aacA-aphD, aphA3, aadE], tetracycline [71/tet(M), tet(K)], ciprofloxacin [29], chloramphenicol [29/catpC221], and trimethoprim-sulfamethoxazole [50/dfrG, dfrK]. The dfrK gene was revealed as part of the radC-integrated Tn559 in two SP isolates. Virulence genes detected among SP isolates were as follow [percentage of isolates]: siet [100], se-int [100], lukS/F-I [100], seccanine [7], and expB [7]. The single MRSA-mecA detected was typed as t011-ST398/CC398-agrI-SCCmecV and was MDR. The methicillin-susceptible SA isolates were typed as t045-ST5/CC5 (n=2), t10576-ST1660 (n=1), and t005-ST22/CC22 (n=1); the t005-ST22 feline isolate was PVL-positive and the two t045-ST45 isolates were ascribed to Immune Evasion Cluster (IEC) type F. Moreover, the t10576-ST1660 isolate, of potential equine origin, harbored the lukPQ and scneq genes. According to animal clinical history and data records, several strains seem to have been acquired from different sources of the hospital environment, while some SA strains appeared to have a human origin.ConclusionsThe frequent detection of MR and MDR isolates among clinical SP and SA strains with noticeable virulence traits is of veterinary concern, implying limited treatment options available. This is the first description of MRSA-ST398 and MRSP-ST68 in pets in Spain, as well the first report of the dfrK-carrying Tn559 in SP. This evidences that current transmissible lineages with mobilizable resistomes have been circulating as causative agents of infections among pets for years.

Multilocus analysis reveals further genetic differences between Tritrichomonas foetus from cats and cattle

Tritrichomonas foetus isolates from feline and bovine origin has been previously shown to carry a certain degree of genetic heterogeneity. Here, novel candidate molecular markers were developed by means of multilocus sequence typing of the gap2 gene (encoding for T. foetus glyceraldehyde-3-phosphate dehydrogenase), ITS region, the TR7/TR8 variable-length repeat and microsatellite genotyping. These markers were used to characterize T. foetus field isolates from bulls and domestic cats and to compare phylogenetically with the following ATCC isolates: T. foetus isolated from cattle and pig (syn. Tritrichomonas suis), Tritrichomonas mobilensis, Tetratrichomonas gallinarum and Pentatrichomonas hominis. Among them, TFMS10 and TFMS7 were found to be the most polymorphic markers. Moreover, an 809 bp fragment of the gap2 gene was successfully amplified from all the trichomonads included in this study and the sequence analysis revealed differences between T. foetus porcine and feline genotypes and T. mobilensis in comparison to the bovine T. foetus ATCC isolate. The TR7/TR8 repeat pattern was not reproducible, being only consistent the fragments of approximately 110 and 217 bp. Sequence analysis of the latter revealed the existence of 3 SNPs resulting in 98.6 % homology between bovine and feline isolates. A search for similar sequences was carried out to develop a Restriction Length Fragment Polymorphism analysis. A 503 bp region, named TF1, revealed the existence of two BbvI restriction enzyme sites that were able to generate different length fragments for T. foetus feline and bovine isolates. Finally, the neighbour-joining analyses showed that T. foetus porcine genotype clusters together with bovine genotype, whereas T. mobilensis and the feline genotype form a separate cluster.

Temporally separated feline calicivirus isolates do not cluster phylogenetically and are similarly neutralised by high-titre vaccine strain FCV-F9 antisera in vitro.

ObjectivesFeline calicivirus (FCV) is a highly variable and globally important feline pathogen for which vaccination has been the mainstay of control. Here, we test whether the continued use of FCV-F9, one of the most frequently used vaccine strains globally, is driving the emergence of vaccine-resistant viruses in the field.MethodsThis study made use of two representative panels of field isolates previously collected from cats visiting randomly selected veterinary practices across the UK as part of separate cross-sectional studies from 2001 and 2013/2014. Phylogenetic analysis and in vitro virus neutralisation tests were used to compare the genetic and antigenic relationships between these populations and FCV-F9.ResultsPhylogenetic analysis showed a typically radial distribution dominated by 52 distinct strains, with strains from both 2001 and 2013/2014 intermingled. The sequence for FCV-F9 appeared to be integral to this phylogeny and there were no significant differences in the genetic distances within each studied population (intra-population distances), or between them (inter-population distances), or between each population and FCV-F9. A 1 in 8 dilution neutralised 97% and 100% of the 2001 and 2013/14 isolates, respectively, and a 1 in 16 dilution neutralised 87% and 75% of isolates, respectively. There was no significant difference either in variance between the FCV-F9 neutralising titres for the two populations, or in the distribution of neutralisation titres across the two populations.Conclusions and relevanceAlthough FCV is a highly variable virus, we found no evidence for a progressive divergence of field virus from vaccine strain FCV-F9, either phylogenetically or antigenically, with FCV-F9 antisera remaining broadly and equally cross-reactive to two geographically representative and temporally separated FCV populations. We suggest this may be because the immunodominant region of the FCV capsid responsible for neutralisation may have structural constraints preventing its longer term progressive antigenic evolution.

PSI-25 development of local Kansas E. coli UTI antibiograms to improve antimicrobial stewardship in companion animal medicine

Abstract Urinary tract infections are common in dogs, but rare in cats. Antimicrobial susceptibility testing of urine isolates is required to determine optimal antimicrobial therapy, but empirical antimicrobial guidelines are needed while culture is pending or if testing is declined. Antibiograms are summaries of local susceptibility trends that assist clinicians in selecting empirical antimicrobial therapy. Antibiograms were developed from E. coli feline (N = 138) and canine (N = 640) urinary isolates submitted by the KSU Veterinary Health Center and private veterinary practices from 2013–2017. Results showed a high prevalence of resistance among feline isolates to amoxicillin-clavulanate (99.3%, S ≤ 0.25) and ampicillin (99.3%, S ≤ 0.25), but lower prevalence among canine isolates (amoxicillin/clavulanate 7.7% S ≤ 8), ampicillin 46.7%, S ≤ 8). Resistance to other antimicrobials was uncommon, with no antimicrobial agents demonstrating resistance above 6% in feline isolates, or above 14% in canine isolates. Canine isolates from private veterinary practices had increased resistance as compared with KSU isolates to orbifloxacin (9.5% vs 0.1%) and pradofloxaxin (9.4% vs 0.1%). Application of different breakpoints and differences in antibiotic exposures may explain the disparity of Beta-Lactam resistance between cats and dogs. Different use patterns between hospitals may explain the disparity between fluoroquinolone resistance. These findings emphasize the need for definitive urine culture and susceptibility testing in pets with UTIs, so that appropriate and effective antimicrobial therapy can be prescribed. Veterinary clinicians in Kansas can use these antibiogram results in addition to following stewardship guidelines to maximize successful UTI therapy for veterinary patients and minimize development of antimicrobial resistance for the One Health community.

Adenovirus Isolated From a Cat Is Related to Human Adenovirus 1.

An adenovirus (AdV) has been isolated from the rectal swab of a domestic cat (Felis catus) and named feline adenovirus (FeAdV) isolate. It replicates and causes cytopathological effects in many human, feline, other mammalian cell lines that have both Coxsackie-adenovirus-receptor and integrins. Its antigens cross-react with anti-human adenovirus antibodies in immunofluorescence and immunocytochemistry assays. Electron microscopy revealed typical extracellular icosahedral particles and pseudo arrays inside cells. Sequence analysis of hexon and fiber genes indicates that this virus might belong to human adenovirus (HAdV) C species and might be a variant of type 1. In the fiber protein, three altered amino acids occur in the shaft; four altered residues are found in the knob region as compared to a European HAdV might be type 1 isolate (strain 1038, D11). One alteration affects amino acid 442 forming an RGS motif in an alanine rich region that might be an alternative way to bind integrins with subsequent internalization. Substitutions in the hexon sequence are silent. As compared to published HAdV sequences, the fiber is related to the original American prototype and recently described Taiwanese HAdV 1 isolates, but the hexon sequences are related to adenovirus isolates from France, Germany, Japan, and Taiwan. Serology carried out on FeAdV infected M426 cells indicates a prevalence of IgG in 80% of domestic cats in Delaware, United States. FeAdV isolate seems to be a recently recognized virus with possible pathogenic effects and, simultaneous human and feline infections are possible. Further molecular and biological characterization of this feline adenovirus isolate, as well as studies on both human and feline epidemiology and pathomechanisms, especially in endangered big cats, are warranted. FeAdV might have further practical advantages. Namely, it could be utilized in both human and feline AIDS research, developed into diagnostic tools, and gene therapy vectors in the near future.

Virulence gene profiling and ompA sequence analysis of Pasteurella multocida and their correlation with host species

This study describes the prevalence of capsule biosynthesis genes, LPS genotypes, virulence associated genes and the analysis of the outer membrane protein (ompA) sequence of Pasteurella multocida isolates (n = 180) from different locations in Hungary, from various host species, including humans. When combining capsular types with LPS genotypes, eight capsule - LPS genotype combinations were detected. A: L3 was the most dominant in bovine and porcine isolates, A: L1 in feline and human isolates, while D: L3 was the most common among strains from small ruminants. The P. multocida toxin encoding gene toxA was highly prevalent among small ruminant and porcine strains, while in human, feline and bovine isolates it could not be detected. Combination of the tested virulence associated genes (hgbA, nanH, hgbB, tbpA, pfhA, hsf1, hsf2, tadD, ptfA) classified our P. multocida isolates into 13 different virulence gene profiles (VGPs). These VGPs showed an association with host species. Analysis of the ompA sequence data confirmed this distribution by host species, which may indicate that host adaptation is taking place. The typing scheme used in this study may be useful in epidemiological investigations.

Highly Pathogenic Avian Influenza A(H5N6) in Domestic Cats, South Korea.

In December 2016, highly pathogenic avian influenza (HPAI) infection with systemic pathologic lesions was found in cats in South Korea. Genetic analyses indicated that the feline isolates were similar to HPAI H5N6 viruses isolated in chicken farms nearby. This finding highlights the need for monitoring of domestic mammals during HPAI outbreaks.

Characterization, distribution, antimicrobial resistance and resistance risk factors in staphylococci isolated from cats from 2001 to 2014.

Relatively few studies have been published describing the patterns of staphylococcal isolation and antimicrobial resistance over time in cats. The objective of this retrospective study was to determine the frequency, location, characteristics and antimicrobial resistance profiles of staphylococci isolated by the Louisiana Animal Disease Diagnostic Laboratory between the years 2001 and 2014. All feline staphylococcal isolates were classified phenotypically. Isolates corresponding to known or possibly pathogenic species (Staphylococcus intermedius group (SIG) and Staphylococcus aureus (SA)) as well as Staphylococcus epidermidis (SE) and non‐speciated coagulase‐negative staphylococci (CNS) were further evaluated to determine antimicrobial resistance patterns. A total of 519 staphylococci were isolated. The largest percentage of isolates was CNS, representing 39.3% of the total, while SIG, SE, SA and non‐speciated coagulase positive staphylococci (CPS) represented 18.1%, 10.2%, 8.3% and 7.3%, respectively. Methicillin resistance (MR) was identified in 57.1% of SA and 20.5% of SIG. Resistance to 3 or more antimicrobial classes (multidrug resistance; MDR) was demonstrated in 54.5% of SA and 23.9% of SIG. The prevalence of MDR increased over time in both SIG and SA, while the prevalence of MR increased over time in SIG. An increase in mean antimicrobial resistance score over time was seen in SIG. This study demonstrates a high and increasing prevalence of MDR in SIG and SA, as well as increasing prevalence of MR in SIG isolated from cats.

Prevalence and genotypes of Giardia lamblia from stray dogs and cats in Guangdong, China.

Giardia lamblia is a worldwide zoonotic intestinal parasite that infects humans and a wide range of mammals including dogs and cats, causing giardiasis with diarrhea. To investigate the infection and distribution of G. lamblia genotypes from stray dogs and cats in Guangdong, China according to different districts, gender and ages, fecal samples were collected and examined by microscopy, and all isolates were genotyped by PCR amplification using beta-giardin (bg) and triose phosphate isomerase (tpi) genes as molecular markers. The results showed that the prevalence of dogs and cats was 10.8% (57/527) and 5.8% (6/104), respectively. Sixty-one samples were detected by microscopy and 63 were amplified and successfully sequenced by the PCR. Based on the phylogenetic analysis, 25 canine isolates (24 assemblages AI and 1 assemblage D) were genotyped by tpi gene and 57 canine isolates (26 assemblages AI, 18 assemblages C and 13 assemblages D) genotyped by bg gene; 6 feline isolates were identified as assemblage AI by tpi gene, and as 3 assemblages AI and 3 assemblages F by bg gene. The dominant genotypes were assemblage AI in younger dogs (assemblage C in adult dogs) and assemblage C in male dogs (assemblage AI in female dogs). Mixed genotype infections were found in different age and gender groups. The results indicated that G. lamblia from stray dogs and cats in Guangdong province had a zoonotic potential with assemblage AI as the prevalent genotype. The different risk factors (age and sex) may have an impact on the infection of different genotypes.