Feline Calicivirus In Cats Research Articles

Comparison of PCR, Nested PCR, and RT-LAMP for Rapid Detection of Feline Calicivirus Infection in Clinical Samples.

Feline calicivirus (FCV) is a highly contagious virus that causes upper respiratory tract disease, commonly known as cat flu. It is widely distributed worldwide and poses a major threat to feline health. Therefore, it is essential to find an efficient and rapid method for detecting FCV. In this study, the colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay, using neutral red as an indicator, was developed and validated to target the ORF2 gene of FCV for the first time. Additionally, the study compared the diagnostic abilities of polymerase chain reaction (PCR), nested PCR, and RT-LAMP assays for detecting FCV in clinical samples. The optimized RT-LAMP amplification was carried out at 56.3 °C. The technique visually detected FCV within 70 min, with a limit of detection of 14.3 × 101 copies/µL, and showed no cross-reactivity with other feline pathogens. Out of 54 oropharyngeal swab samples, 17 tested positive for FCV using both nested PCR and RT-LAMP, while only one tested positive using conventional PCR. The positivity rate was higher with nested PCR and RT-LAMP (31.48%) compared to conventional PCR (1.85%). Consequently, these results demonstrated the effectiveness of the colorimetric RT-LAMP assay developed in this study as an alternative for diagnosing FCV in cats.

Detection of Mycoplasma spp. and feline calicivirus in cats with ocular surface disease.

To survey the prevalence of pathogens in shelter-housed cats with active ocular surface disease (OSD). A total of 255 shelter-housed domestic cats with evidence of active OSD. No normal, unaffected cats were sampled. OSD scoring was performed on cats with active OSD. Combined oropharyngeal/conjunctival swabs were submitted for rt-PCR/PCR for feline herpesvirus (FHV-1), feline calicivirus (FCV), Chlamydia spp. (CHL), Bordetella bronchiseptica (BORD), and Mycoplasma spp. (MYC). Pathogens were detected as follows: 76.4% (195/255) MYC, 57.6% (147/255) FHV-1, 42.7% (109/255) FCV, 26.7% (68/255) CHL, and 5.5% (14/255) BORD. Monoinfections affected 21.1% (54/255) animals, with MYC being the most common monoinfection (12.5%, 32/255), followed by FHV-1 (4.7%, 12/255), followed by CHL (2.4%, 6/255), followed by FCV (1.6%, 4/255), with no animals having a BORD monoinfection. Dual infections affected 36.4% of animals (93/255), with MYC detected in 30.1% (77/255) dual infections and FCV detected in 12.9% (33/255) dual infections. Dual infections with MYC and FCV together were detected in 9.8% (25/255) animals. Many animals (35.3%, 90/255) were found to be affected by 3 or more pathogens, and 7.1% (18/255) animals had no pathogens detected. OSD scores were not influenced by any variable assessed, including the number and type of pathogens detected. MYC, FHV-1, FCV, and CHL were commonly detected in this group of animals with OSD. Both MYC and FCV (alone or in combination with each other) were detected in multiple animals with active OSD, supporting prior evidence that either may independently act as a primary ocular surface pathogen.

Molecular investigation of feline calicivirus in cats in Mosul city, Iraq

The study included 200 cats of different ages, genders, types of breeding, source, vaccination programs, and health status. They were examined clinically and traditionally and recorded clinical signs appearing on them, and swabs were collected from the eye's conjunctiva and the pharyngeal area. RNA was extracted from the swabs and then converted into a cDNA molecule to investigate viral nucleic acid from collected swabs. Then, the open reading template gene two was detected using the primer for this within the applied polymerase chain reaction technique. The Molecular method found the highest infection rate in the oropharyngeal compared with conjunctival swabs. It was found in the highest percentage of infection in the age group more than six months, and the rate of infection decreased with age and in cats outdoors management and imported ones. While nonvaccinated cats recorded the highest rate of infection with the feline calicivirus. In conclusion, feline calicivirus affected the cats in Mosul, Iraq.

High occurrence of felid alphaherpesvirus 1 and feline calicivirus in domestic cats from southern Brazil

ABSTRACT: Felid alphaherpesvirus 1 (FeHV-1) and feline calicivirus (FCV) affect cats worldwide. The aim of this study was to evaluate the frequency of occurrence of FeHV-1 and FCV in cats with clinical signs of respiratory, oral and/or ocular disease. Samples were collected from cats cared for in veterinary ambulatory and clinics and submitted to molecular detection and viral isolation. Of the 49 cats evaluated, 45 (92%) were positive for at least one of the viruses; 82% (40/49) were positive for FeHV-1 and 41% (20/49) for FCV. Of these, 31% (15/49) were coinfection cases. For FeHV-1, 45% (18/40) of the cats tested were positive from the collection of eye swab, and the same percentage (9/20) was obtained for the FCV by the oral swab. FeHV-1 and/or FCV were isolated in 35% (17/49) of the samples. The main clinical sign observed was ocular secretion in 71% (35/49) of cats, characterized as mild serous, purulent or serosanguineous, and in some cases associated with ocular injury and marked chemosis. Our findings demonstrate the high occurrence of FeHV-1 and FCV in domestic cats in southern Brazil and indicate that measures should be implemented to improve the diagnostic, prevention and management against of these important diseases.

Identification of feline calicivirus in cats with enteritis.

Feline calicivirus (FCV) is a major pathogen of cats associated with either respiratory disease or systemic disease, but its possible role as an enteric pathogen is neglected. Using RT-PCR, the RNA of FCV was identified in 25.9% (62/239) of stools of cats with enteritis and in 0/58 (0%) of cats without diarrhoea or other clinical signs. Isolates of enteric origin were obtained and a large 3.2-kb portion of the genome was sequenced, encompassing the 3' end of the RNA polymerase, the capsid protein precursor and the minor capsid protein. Also, the complete genome sequence of one such strain, the 160/2015/ITA, was determined. Upon sequence analysis, the enteric viruses were found to be genetically heterogeneous and to differ from each other and from isolates of respiratory origin. The enteric isolates were found to be more resistant to low pH conditions, to trypsin and to bile treatment than respiratory isolates. Overall, these findings are consistent with the hypothesis that some FCVs may acquire enteric tropism and eventually act as enteric pathogens. Whether this enteric tropism is maintained stably and whether it may affect, to some extent, the ability of the virus to trigger the classical and/or hypervirulent forms of disease should be assessed. Also, FCV should be included in the diagnostic algorithms of enteric diseases of cats to gain further information about FCV strains displaying enteric pathotype.

Prevalence of feline calicivirus in cats with odontoclastic resorptive lesions and chronic gingivostomatitis

Feline odontoclastic resorptive lesion (FORL) and feline chronic gingivostomatitis (FCGS) are two of the most common diseases of the feline oral cavity. While evidence is emerging that FCGS is caused by gingival inflammation initiated and perpetuated by the oral microbiota, little is known in this regard for FORL. Feline calicivirus (FCV) has been associated with the presence of FCGS and is thought to play a role in the initiation of this disease. In this study, the incidence of FCV was investigated in cats with FORL and FCGS, and compared to unaffected controls. FCV was detected by viral culture. The incidence of FCV was as follows: 6 (24.0%) of 24 control cats, 9 (22.5%) of 40 cats with FORL and 15 (60.0%) of 25 cats with FCGS were positive for FCV. There was a significant difference in FCV incidence between all the groups (p=0.003) but none between the control group and the FORL group. However, significant differences were observed in the incidence of FCV between control and FCGS (p=0.010) and between FORL and FCGS (p=0.006). It is concluded that although FCV may be associated with FCGS, it appears unlikely to play a role in FORL.

ДОСЛІДЖЕННЯ ТЕРАПЕВТИЧНОЇ ЕФЕКТИВНОСТІ ГІПЕРІМУННОЇ СИРОВАТКИ ПРОТИ КАЛІЦИВІРУСНОЇ ІНФЕКЦІЇ КОТІВ

In Ukraine, as elsewhere in the world, feline calicivirus is one of the most common infectious diseases of cats. The main reason is the continuous growth of infections in animal populations, and high recurrence interest of feline calicivirus in cats that have undergone treatment. In addition, nowadays, it is a chronic disease. Therefore, according to existing treatment regimens, there is a need to develop new, more effective, aimed at the elimination of the pathogen through the appointment of immunomodulators, antibiotics with simultaneous application of specific medicine, including hyperimmune serum against feline calicivirus.The article presents experimental data on the study of various schemes of complex treatment for feline calicivirus using Fosprenil, Tylozine and specific hyperimmune serum against feline calicivirus. Apart from antigenic reaction, medical hyperimmune serum show immunomodulatory properties. It is proved that the use of specific globulin at a dose of 2 ml per animal in the treatment of cats increases the effectiveness of therapy by 25% compared with the use of schemes that included only antibiotic and immune modulator. At the same time, it is known, that the use of globulin without antibiotics and immunomodulators does not show high therapeutic efficacy.

Feline calicivirus and other respiratory pathogens in cats with Feline calicivirus-related symptoms and in clinically healthy cats in Switzerland.

BackgroundCats with feline calicivirus (FCV)-related symptoms are commonly presented to veterinary practitioners. Various clinical manifestations have been attributed to FCV, i.e. upper respiratory tract disease (URTD), oral ulcerations, gingivostomatitis, limping syndrome and virulent systemic disease. Additionally, healthy cats can shed FCV. The aims of this study were 1) to investigate the frequency of FCV in cats with FCV-related symptoms and in healthy cats in Switzerland, 2) to assess risk and protective factors for infection, such as signalment, housing conditions, vaccination, and co-infection with URTD-associated pathogens, and 3) to address the association between clinical symptoms and FCV infection.ResultsOropharyngeal, nasal and conjunctival swabs were collected in 24 veterinary practices from 200 FCV-suspect and 100 healthy cats originating from 19 cantons of Switzerland. The samples were tested for FCV using virus isolation and reverse-transcription real-time quantitative polymerase chain reaction (qPCR) and for feline herpesvirus-1 (FHV-1), Mycoplasma felis, Chlamydophila felis, Bordetella bronchiseptica using real-time qPCR. Within the two populations (FCV-suspect/healthy), the observed PCR prevalences were: FCV 45 %/8 %, FHV-1 20 %/9 %, C. felis 8 %/1 %, B. bronchiseptica 4 %/2 %, M. felis 47 %/31 % and any co-infections thereof 40 %/14 %. Based on multivariable regression models amongst FCV-suspect cats (odds ratio [95 % confidence interval]), co-infection with M. felis (1.75 [0.97; 3.14]), group housing (2.11 [1.02; 4.34]) and intact reproductive status (1.80 [0.99; 3.28]) were found to be risk factors for FCV infection. In healthy cats, intact reproductive status (22.2 [1.85; 266.7]) and group housing (46.4 [5.70; 377.7]) were found to be associated with FCV infection. Based on an univariable approach, FCV-suspect cats were found to be significantly less often FCV-positive when vaccinated (0.48 [0.24; 0.94]). Oral ulcerations, salivation, gingivitis and stomatitis, but not classical signs of URTD were significantly associated with FCV infection (all p < 0.001).ConclusionsFCV was detected in less than half of the cats that were judged FCV-suspect by veterinary practitioners. For a clinical diagnosis, FCV-related symptoms should be revisited. FCV infection was present in some healthy cats, underlining the importance of asymptomatic carriers in FCV epidemiology. To reduce FCV-related problems in multi-cat environments, reduction of group size in addition to the generally recommended vaccination are advocated.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-015-0595-2) contains supplementary material, which is available to authorized users.

Determination of Feline calicivirus in cats in Ahvaz district, Southwest of Iran by RT-PCR (a preliminary study)

Feline calicivirus (FCV) is a highly infectious respiratory pathogen of domestic cats with a widespread distribution. In order to assess how FCV circulates in feral and household cats, we have carried out the first study on the FCV detection in Ahvaz district from December 2008 to November 2009. Oropharyngeal, nasal and ocular swabs of one hundred cats (70 feral and 30 household) were evaluated by reverse transcription polymerase chain reaction (RT-PCR) procedure for the detection of FCV. The influence of sex, age, social status and clinical signs on the probability of infection was analyzed using statistical Fisher’s exact test. Overall, feline calicivirus was detected in 4/100 (4%) of sampled cats; 13.3% of the household cats were FCV positive compared to 0% of feral cats. According to several factors including younger cats (under 6 months of age), multiple cat household and clinical findings, differences were significant (p 0.05). To the best of our knowledge, this is the first report indicating the presence of FCV in cats in Iran. Due to low prevalence of FCV infection and the fact that feral cats live solitarily, it was concluded that this viral infection don’t spread readily within feral populations. However special measures are recommended to avoid infection of susceptible and unvaccinated cats.

Vaccine efficacy of recombinant feline herpesvirus type 1 expressing immunogenic proteins of feline calicivirus in cats.

We previously constructed a recombinant feline herpesvirus type 1 (FHV1), C7301dlTK-Cap, which contains an entire open reading frame encoding the capsid protein of feline calicivirus (FCV) F4 strain in the deleted locus of the thymidine kinase (TK) deficient mutant (C7301dlTK) of FHV1. In this report, we carried out in vivo experiments to assess the vaccine efficacy of the recombinant C7301dlTK-Cap against FCV and FHV1 infections in cats. As a result, two vaccinations with the C7301dlTK-Cap by intraocular, intranasal and oral routes protected cats to a significant degree against subsequent virulent challenges with both parent FCV F4 and FHV1 C7301 strains. The results are applicable for the further development of a new genetically engineered polyvalent vaccine for cats.

Recombinant feline herpesvirus type 1 expressing immunogenic proteins inducible virus neutralizing antibody against feline calicivirus in cats

In this study, an entire open reading frame encoding the capsid protein of feline calicivirus (FCV) F4 strain was inserted into the deletion locus (SmaI site) of the thymidine kinase (TK) deficient mutant (C7301dlTK) of feline herpesvirus type 1 (FHV-1) and the resulting recombinant virus was designated as C7301dlTK-Cap. Expression of the FCV antigens by C7301dlTK-Cap was confirmed by indirect immunofluorescence assay and immunoblot analysis. To assess whether the recombinant virus can induce virus neutralizing (VN) antibody against FCV in the natural host, three cats were inoculated intranasally and orally with C7301dlTK-Cap (two cats) or C7301dlTK (one cat). As a result, sera collected from cats inoculated with the C7301dlTK-Cap possessed VN antibody against FCV. This recombinant virus is expected as a new polyvalent recombinant vaccine against FHV-1 and FCV infections.