Feline calicivirus is among the most common pathogenic microorganisms in upper respiratory tract disease (URTD) and oral lesions of cats. It leads to stomatitis, oral ulceration, ocular and nasal discharge, conjunctivitis, fever, lameness, anorexia, hypersalivation, pneumonia, respiratory distress, coughing, and depression in infected cats. This study aimed to determine the role of Feline calicivirus (FCV) in cats with the upper respiratory tract disease in the Diyarbakir region, Turkey, to provide treatment for infected cats and contribute to the disease prophylaxis. The study material consisted of 10 cats (control group) considered to be healthy according to the clinical examination and 20 cats with URTD that were not vaccinated against Feline calicivirus infection of different breeds, ages, and genders brought to Dicle University Veterinary Faculty Prof. Dr. Servet SEKIN Polyclinic with URTD. After routine clinical examinations of the animals, oral and conjunctival swabs and blood samples were taken. Hematological and biochemical analyzes of blood samples were performed. Swab samples were analyzed by the polymerase chain reaction (PCR) method for the diagnosis of the agent. Oral lesions, hypersalivation, ocular and nasal discharge, coughing, and breathing difficulties were seen in clinical examinations of cats with URTD. Feline calicivirus was detected in only one cat’s conjunctival swab sample in PCR analyses. As a result, we found that Feline calicivirus infection was present in cats with URTD in the Diyarbakir region, and 5% positivity was found in cats with clinical symptoms according to PCR analysis.

Feline calicivirus is among the most common pathogenic microorganisms in upper respiratory tract disease (URTD) and oral lesions of cats. It leads to stomatitis, oral ulceration, ocular and nasal discharge, conjunctivitis, fever, lameness, anorexia, hypersalivation, pneumonia, respiratory distress, coughing, and depression in infected cats. This study aimed to determine the role of Feline calicivirus (FCV) in cats with the upper respiratory tract disease in the Diyarbakir region, Turkey, to provide treatment for infected cats and contribute to the disease prophylaxis. The study material consisted of 10 cats (control group) considered to be healthy according to the clinical examination and 20 cats with URTD that were not vaccinated against Feline calicivirus infection of different breeds, ages, and genders brought to Dicle University Veterinary Faculty Prof. Dr. Servet SEKIN Polyclinic with URTD. After routine clinical examinations of the animals, oral and conjunctival swabs and blood samples were taken. Hematological and biochemical analyzes of blood samples were performed. Swab samples were analyzed by the polymerase chain reaction (PCR) method for the diagnosis of the agent. Oral lesions, hypersalivation, ocular and nasal discharge, coughing, and breathing difficulties were seen in clinical examinations of cats with URTD. Feline calicivirus was detected in only one cat's conjunctival swab sample in PCR analyses. As a result, we found that Feline calicivirus infection was present in cats with URTD in the Diyarbakir region, and 5% positivity was found in cats with clinical symptoms according to PCR analysis.

OBJECTIVE To determine whether exposure to UV germicidal irradiation (UVGI) reduces concentrations of viable aerosolized microorganisms (attenuated strains of common veterinary pathogens) in a simulated heating, ventilation, and air conditioning (HVAC) system. SAMPLE 42 air samples seeded with bacteriophage MS2 or attenuated strains of Bordetella bronchiseptica, feline calicivirus, feline herpesvirus-1, canine parvovirus, or canine distemper virus (6/microorganism) or with no microorganisms added (6). PROCEDURES A simulated HVAC unit was built that included a nebulizer to aerosolize microorganisms suspended in phosphate-buffered water, a fan to produce airflow, 2 UVGI bulb systems, and an impinger for air sampling. Ten-minute trials (3 with UVGI, 3 without UVGI, and 1 negative control) were conducted for each microorganism. Impingers collected microorganisms into phosphate-buffered water for subsequent quantification with culture-based assays. Results for samples yielding no target microorganisms were recorded as the assay's lower limit of detection. Statistical analysis was not performed. RESULTS The UVGI treatment resulted in subjectively lower concentrations of viable MS2, B bronchiseptica, and canine distemper virus (arithmetic mean ± SD log10 microorganism reduction, 2.57 ± 0.47, ≥ 3.45 ± 0.24, and ≥ 1.50 ± 0.25, respectively) collected from air. Feline herpesvirus-1 was detected in only 1 sample without and no samples with UVGI treatment. Feline calicivirus and canine parvovirus were not detectable in any collected samples. CONCLUSIONS AND CLINICAL RELEVANCE Results for some surrogates of veterinary pathogens suggested a potential benefit to supplementing manual disinfection practices with UVGI-based air cleaning systems in animal care environments. Further research is needed to investigate the utility of UVGI in operating HVAC systems.

Intraocular production of Toxoplasma gondii-specific antibody in cats has been estimated by comparing the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of total immunoglobulins in serum and aqueous humor (Goldmann-Witmer coefficient; aqueous antibody coefficient; C value). It has been proposed that in human beings, comparison of the ratio of T gondii-specific antibody in aqueous humor and serum with the ratio of antibodies against a nonocular pathogen in serum and aqueous humor is more accurate than methods using total immunoglobulin quantification. We developed an ELISA for detection of calicivirus-specific antibodies in the serum and aqueous humor of cats. By evaluating calicivirus-specific antibody concentrations in the aqueous humor of healthy and diseased cats, calicivirus was assessed as a nonintraocular pathogen. The ratio of T gondii-specific antibodies in the aqueous humor and serum and the ratio of calicivirus-specific antibodies in serum and aqueous humor were evaluated as a means of estimating intraocular T gondii-specific antibody production. A field strain of feline calicivirus was isolated, cultured, and purified. A calicivirus-specific IgG ELISA was developed for detection of feline calicivirus-specific IgG in serum and aqueous humor. Calicivirus-specific IgG was measured in the serum and aqueous humor from 3 groups of control cats. Results suggested that calicivirus is a nonintraocular pathogen in cats and that calicivirus IgG detected in aqueous humor is attributable to leakage across a damaged blood-ocular barrier. Intraocular production of T gondii-specific antibodies was estimated, using 2 formulas. The C value was calculated by multiplying the ratio of T gondii-specific IgM or IgG in aqueous humor and serum by the ratio of total immunoglobulins (using the corresponding IgM or IgG class) in serum and aqueous humor. The Ctc value (Toxoplasma-calicivirus Goldmann-Witmer coefficient) was calculated by multiplying the ratio of T gondii-specific IgM or IgG in aqueous humor and serum by the ratio of calicivirus-specific IgG in serum and aqueous humor. Serum and aqueous humor samples were obtained from 41 client-owned cats with uveitis, and T gondii-specific C values and Ctc values were calculated. Toxoplasma gondii-specific IgM or IgG C values of 10 or greater or T gondii-specific IgM or IgG Ctc values of 1 or greater were considered to be suggestive of intraocular T gondii-specific antibody production. Of the 41 cats, 20 (48.7%) had evidence of intraocular production of T gondii-specific antibody on the basis of either an IgM or IgG C value of 10 or greater. A Ctc value could not be calculated in 3 cats because calicivirus-specific IgG was not present in aqueous humor. Of the 38 cats for which Ctc values could be calculated, 25 (65.8%) had evidence of intraocular production of T gondii-specific antibody on the basis of either an IgM or IgG Ctc value of 1 or greater. The C values and Ctc values were in agreement for 75.9% of IgM containing samples and 75% of IgG containing samples. Sensitivity, specificity, predictive value of a positive test result, and predictive value of a negative test result for an IgM or IgG C value, when compared with the corresponding IgM or IgG Ctc value were determined. The results indicate that use of the C value for estimation of intraocular T gondii-specific antibody production will result in 28.6 (IgM) to 50% IgG) false-negative results and 12.5% (IgM and IgG) false-positive results, when compared with the Ctc value.

Feline panleukopenia virus (FPV), feline calicivirus (FCV), and feline herpesvirus type-1 (FHV-1) are major infectious pathogens in cats. We evaluated the immunogenicity of a new vaccine containing inactivated FPV, two FCVs, and FHV-1 in animals. An FPV, two FCVs, and an FHV-1 isolate were continuously passaged 70, 50, 80, and 100 times in CRFK cells. FP70, FC50, FC80, and FH100 were propagated and used as vaccine antigens. Two inactivated feline virus vaccines, feline rehydragel-adjuvanted vaccine (FRAV) and feline cabopol-adjuvanted vaccine (FCAV) were prepared and inoculated into mice and guinea pigs. Humoral immune responses were measured using hemagglutination inhibition (HI) for FPV and virus-neutralizing antibody (VNA) for two FCVs and FHV-1 tests. Serial passages in CRFK cells resulted in increase in titers of FPV and two FCVs but not FHV-1 The FCAV induced higher mean HI and VNA titers than the FRAV in guinea pigs; therefore, the FCAV was selected. Cats inoculated with FCAV developed a mean HI titer of 259.9 against FPV, and VNA titers of 64, 256, and 3.2 against FCV17D03, FCV17D283, and FHV191071, respectively. Therefore, cats inoculated with the FCAV showed a considerable immune response after receiving a booster vaccination.

OBJECTIVE To identify associations between microbes and host genes in cats with feline chronic gingivostomatitis (FCGS), a debilitating inflammatory oral mucosal disease with no known cause, compared with healthy cats and cats with periodontitis (control cats). ANIMALS 19 control cats and 23 cats with FCGS. PROCEDURES At least 1 caudal oral mucosal swab specimen was obtained from each cat. Each specimen underwent unbiased metatranscriptomic next-generation RNA sequencing (mNGS). Filtered mNGS reads were aligned to all known genetic sequences from all organisms and to the cat transcriptome. The relative abundances of microbial and host gene read alignments were compared between FCGS-affected cats and control cats and between FCGS-affected cats that did and did not clinically respond to primary treatment. Assembled feline calicivirus (FCV) genomes were compared with reverse transcription PCR (RT-PCR) primers commonly used to identify FCV. RESULTS The only microbe strongly associated with FCGS was FCV, which was detected in 21 of 23 FCGS-affected cats but no control cats. Problematic base pair mismatches were identified between the assembled FCV genomes and RT-PCR primers. Puma feline foamy virus was detected in 9 of 13 FCGS-affected cats that were refractory to treatment and 5 healthy cats but was not detected in FCGS-affected cats that responded to tooth extractions. The most differentially expressed genes in FCGS-affected cats were those associated with antiviral activity. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that FCGS pathogenesis has a viral component. Many FCV strains may yield false-negative results on RT-PCR-based assays. Coinfection of FCGS-affected cats with FCV and puma feline foamy virus may adversely affect response to treatment.

The prevalence of the causative agents of feline upper respiratory tract disease (URTD) has been previously documented in many regions worldwide, but has yet to be reported in eastern Canada. The objectives of this study were to determine the prevalence of feline herpesvirus(-1) (FHV(-1)), feline calicivirus (FCV), Chlamydia felis (C. felis), and Bordetella bronchiseptica (B. bronchiseptica) in a population of shelter cats with clinical signs related to URTD on Prince Edward Island, Canada; to compare the prevalence of FHV(-1) and FCV as detected by polymerase chain reaction (PCR) and virus isolation (VI) in this population; and lastly, to determine whether factors, such as co-infections, time of year, concurrent feline leukemia virus (FeLV)- or feline immunodeficiency virus (FIV)-positive status, or clinical signs, were associated with prevalence of particular pathogens. Conjunctival, nasal mucosal, and oropharyngeal swabs were collected from 82 cats with clinical signs consistent with URTD. Samples were pooled in transport medium and PCR was used to detect FHV(-1), FCV, and C. felis and VI was also used to detect FHV(-1) and FCV. A separate swab was submitted for aerobic bacterial culture to detect B. bronchiseptica. Feline herpesvirus(-1) (FHV(-1)) was the most prevalent in this population, followed by C. felis, B. bronchiseptica, and FCV. Of the 4 cats that were positive for B. bronchiseptica, 3 were concurrently positive for FHV(-1). All positive B. bronchiseptica cultures were resistant to cefovecin. The prevalence for FHV(-1) was lowest in autumn (seasons P < 0.001) and was positively associated with the presence of nasal discharge (P = 0.018) and coughing (P = 0.043).

Objective: To determine whether 14-day topical ocular administration of high doses of feline recombinant interferon omega (FelFN) or human recombinant interferon alpha-2b (HulFN) solution improves clinical disease and decreases virus shedding in cats with naturally acquired viral keratoconjunctivitis. Animals: 36 cats with upper respiratory tract disease and ocular involvement. Procedures: Cats received 1 drop of FelFN solution (1 × 10(6) U/mL), HulFN solution (1 × 10(6) U/mL), or saline (0.9% NaCl) solution (12 cats/group) in each eye twice daily for 14 days (beginning day 1). Oropharyngeal and conjunctival swab samples were collected from each cat before (day 0) and on day 14 of treatment for virus isolation (VI) and real-time quantitative PCR (RT-qPCR) testing to detect feline herpesvirus-1 and feline calicivirus. Subjective clinical scores were recorded on days 0, 3, 7, 10, and 14. Results: The number of cats for which feline herpesvirus-1 was detected via VI or RT-qPCR assay was generally (albeit not always significantly) lower on day 14, compared with day 0 findings; however, findings on days 0 or 14 did not differ among groups. The number of cats for which feline calicivirus was detected via VI or RT-qPCR assay did not differ significantly between days 0 and 14 for any group. Clinical scores significantly decreased over the 14-day period but did not differ among groups. Conclusions and Clinical Relevance: In cats with naturally occurring viral keratoconjunctivitis, bilateral ocular administration of high doses of FelFN or HulFN twice daily for 14 days did not improve clinical disease or virus shedding, compared with treatment with saline solution.