Rhinotracheitis Research Articles

Serosurvey of mountain lions in southern Arizona.

An understanding of the prevalence of diseases in free‐ranging populations of felids is limited, and there is even less known about the overall health and diseases of wild felids that inhabit or utilize urban areas. We collected serum samples from 9 radiocollared mountain lions (Puma concolor) in the mountains surrounding Tucson, Arizona, USA, from August 2005 to August 2008. We tested serum samples for evidence of exposure to 10 feline viruses: Feline Calicivirus (FCV), Feline Herpesvirus, Feline Enteric Coronavirus, Feline Syncytial Virus–Feline Foamy Virus, Feline Infectious Peritonitis, Feline Immunodeficiency Virus, Feline Panleukopenia Virus (FPLV), Feline Leukemia Virus, Canine Distemper Virus (CDV), and Toxoplasma gondii. The highest prevalences of exposure were: T. gondii (8/9), FPLV (7/9), and FCV (6/9). One male was seropositive for CDV, T. gondii, and FPLV. Mountain lions inhabiting smaller fragmented landscapes and urban areas have more contact with other felids and domesticated animals. Frequent contact among mountain lions, other felids, and domesticated animals can lead to higher risk of exposure and facilitate the spread of the disease from animal to animal. © 2012 The Wildlife Society.

Infectious feline herpesvirus detected in distant bone and tendon following mucosal inoculation of specific pathogen-free cats

Emerging evidence suggests that cats infected with feline herpesvirus-1 (FHV-1) may experience a brief viremic phase. The objective of this study was to determine whether natural routes of FHV-1 inoculation could result in viremic transmission of infectious virus to connective tissues (cortical bone, tendon). Three specific pathogen-free cats were experimentally inoculated with FHV-1 via a combined mucosal (oronasal, ocular) route. Cats were euthanized at the peak of clinical signs to aseptically harvest tissues (cortical bone, tendon, trachea/tongue) for co-culture with a susceptible cell line to promote spread of infectious virus. Viral infection of Crandall-Rees feline kidney cells was microscopically visualized by cytopathic effect (CPE). Additionally, co-culture DNA was extracted either at the point of CPE or 16 days of culture without evidence of CPE, to amplify FHV-1 glycoprotein B gene using real-time PCR. Infectious virus was detected in distant cortical bone (two cats, moderate to severe clinical signs) and tendon (one cat, severe clinical signs). Direct infection of mucosal (trachea, tongue) tissues also was confirmed in these two cats. In contrast, all co-cultured tissues from the third cat (mild clinical signs) were negative for FHV-1 by CPE and PCR. Results of this study demonstrated that early primary FHV-1 viremia may be distributed to distant connective tissues.

ANTIBODY RESPONSE TO VACCINES FOR RHINOTRACHEITIS, CALICIVIRAL DISEASE, PANLEUKOPENIA, FELINE LEUKEMIA, AND RABIES IN TIGERS (PANTHERA TIGRIS) AND LIONS (PANTHERA LEO)

This article presents the results of a study of captive tigers (Panthera tigris) and lions (Panthera leo) vaccinated with a recombinant vaccine against feline leukemia virus; an inactivated adjuvanted vaccine against rabies virus; and a multivalent modified live vaccine against feline herpesvirus, calicivirus, and panleukopenia virus. The aim of the study was to assess the immune response and safety of the vaccines and to compare the effects of the administration of single (1 ml) and double (2 ml) doses. The animals were separated into two groups and received either single or double doses of vaccines, followed by blood collection for serologic response for 400 days. No serious adverse event was observed, with the exception of abortion in one lioness, potentially caused by the incorrect use of the feline panleukopenia virus modified live vaccine. There was no significant difference between single and double doses for all vaccines. The recombinant vaccine against feline leukemia virus did not induce any serologic response. The vaccines against rabies and feline herpesvirus induced a significant immune response in the tigers and lions. The vaccine against calicivirus did not induce a significant increase in antibody titers in either tigers or lions. The vaccine against feline panleukopenia virus induced a significant immune response in tigers but not in lions. This report demonstrates the value of antibody titer determination after vaccination of nondomestic felids.

Evaluation of cytologic findings in feline conjunctivitis

Cytologic examination of smears prepared from ocular swabs of conjunctiva from cats with conjunctivitis permits identification of the type of inflammation and possibly specific microorganisms. Results of studies of the diagnostic utility of cytology for detection of infectious causes of feline conjunctivitis have been inconsistent. The objectives of this study were to describe cytologic findings in cats with conjunctivitis and to compare those findings with results of PCR analysis for feline herpesvirus (FHV-1), Chlamydophila felis (C felis), and Mycoplasma felis (M felis). Conjunctival smears from 88 cats with conjunctivitis and 10 healthy control cats were stained with a Romanowsky stain and evaluated for the type of inflammation and evidence of an infectious agent. PCR analysis for FHV-1, C felis, and M felis was performed. Infectious agents identified by PCR analysis were FHV-1 in 9 cats (10%), C felis in 8 cats (9%), and M felis in 6 cats (7%). Inclusions interpreted as chlamydial inclusions were found in all cytologic smears from cats positive for C felis by PCR analysis and in 3 PCR-negative cats. Inclusions interpreted as Mycoplasma organisms were found in 3 of 6 cats that were PCR-positive for M felis and in 1 PCR-negative cat. FHV-1 inclusion bodies were not detected on cytologic examination. Cytologic examination can be diagnostic for C felis infection when many typical inclusions are present. Cytologic examination was unreliable in diagnosing M felis infection, and viral inclusions of FHV-1 were not found in specimens stained with Romanowsky stains.

Epidemiologically non-feasible singleton reactors at the final stage of BoHV1 eradication: Serological evidence of BoHV2 cross-reactivity

A voluntary marker-independent Bovine Herpesvirus 1 (BoHV1) eradication program started in 1986; in 1998 it changed to a compulsory one. Certification of free regions in European member states is based on Article 10 of directive 64/432/EEC. According to this rule Bavaria is listed as free of BoHV1 since October 2011. Surveillance of BoHV1-free dairy cattle farms is currently performed with quarterly bulk-milk testing. Non-negative bulk-milk results must be confirmed by blood tests in cattle older than nine months. An increased regional rate of non-negative bulk-milk samples and the subsequent detection of epidemiologically non-feasible singleton BoHV1-reactors by analysis of blood were observed at the final stage of eradication in southwest Bavaria.Nineteen case farms (734 animals) defined by singleton reactors born at least two years after certification of the farms as BoHV1-free, 23 negative control (NC) farms (NC I: 321 animals) from the same region, 11 NC-farms (NC II: 423 animals) from an already-certified Article 10 region in northeast Bavaria and two BoHV1-infected farms (264 animals) were analysed using BoHV1-, BoHV2- and Feline Herpesvirus 1 (FeHV1)-neutralisation tests (NTs), and three commercially available ELISAs supplied by Idexx Laboratories, B.V., The Netherlands: the CHEKIT™ Trachitest 2nd Gen. test for milk or serum (Trachitest), Herdchek™ gB- (gB-ELISA) and Herdchek™ gE-ELISA (gE-ELISA). Significantly increased levels of BoHV2 antibodies were observed on case farms compared to NC I or II farms. Additionally, reactivity by gB-ELISA and the Trachitest was significantly increased for animals with BoHV2 neutralising antibodies. Singleton BoHV1-reactors tested negative by gE-ELISA even if an elevated cut-off of 0.95±0.05 was applied. At this cut-off, the gE-ELISA was as sensitive and specific as the gB-ELISA.Comparative titration of milk samples from seropositive animals from a BoHV1-infected dairy cattle farm and from singleton BoHV1-reactors performed in CHEKIT™ Trachitest 2nd Gen. Milk revealed that the slopes of both groups were distinct; therefore, optimised cut-offs for bulk-milk testing to exclude singleton BoHV1-reactors are proposed.

In vitro assessment of the feline cell-mediated immune response against feline panleukopeniavirus, calicivirus and felid herpesvirus 1 using 5-bromo-2′-deoxyuridine labeling

In this study an in vitro assay was optimized to detect feline proliferating lymphocytes as an assessment for the cell-mediated immune response. For this purpose, 5-bromo-2′-deoxyuridine (BrdU) labeling was chosen because of its sensitivity and the possibility of further characterization of proliferating cells. The assay was optimized by selecting the best batch and concentration of fetal bovine serum, β-mercaptoethanol concentration, cell density, BrdU incubation time and antigen presenting cell type. Cats were vaccinated with the attenuated Nobivac vaccine Tricat and the peripheral blood lymphocyte proliferation responses were quantified upon in vitro restimulation with inactivated and infectious feline panleukopenia virus (FPV), feline calicivirus (FCV) and felid herpesvirus 1 (FeHV-1). Proliferation signals were detected with inactivated FeHV-1 in the CD8+ but not in the CD8− T lymphocyte population, with inactivated FCV and FPV in both CD8− and CD8+ T lymphocyte populations. Restimulation with infectious FCV caused significant proliferation in the CD8− T lymphocyte population only while infectious FPV and FeHV-1 seemed to suppress lymphocyte proliferation in both T cell populations. Additional IFN-γ quantification in the culture supernatant revealed a large correlation between the proliferation signals and IFN-γ production, indicating that BrdU labeling is a very reliable technique to assess and characterize feline lymphoproliferative responses to viral antigens in vitro.

Pharmacokinetics of famciclovir and penciclovir in tears following oral administration of famciclovir to cats: a pilot study

To validate a means of collecting tears from cats, develop an assay for quantifying famciclovir and penciclovir in tears, and to assess famciclovir and penciclovir concentrations and pharmacokinetics in the tears of cats being treated orally with famciclovir for suspected herpetic disease. Seven client-owned cats. Cats were treated orally with a median (range) dose of 40 (39-72) mg of famciclovir/kg three times daily for at least 24 h. At various time points following famciclovir administration, tear samples were collected using Schirmer tear test strips. Tear famciclovir and penciclovir concentrations were measured using liquid chromatography-mass spectrometry, and concentration-time profiles were analyzed noncompartmentally. The relationship between famciclovir dose and tear penciclovir concentration near its maximum was evaluated using least squares linear regression. Maximum tear famciclovir concentration of 0.305 μg/mL occurred at 2.64 h; elimination half-life was 2.28 h. Maximum tear penciclovir concentration (0.981 μg/mL) occurred 2.25 h following oral administration of famciclovir; elimination half-life was 2.77 h. A significant positive correlation was noted between famciclovir dose and tear penciclovir concentration at various time points between 0.5 and 3.75 h following drug administration (P = 0.025). Tear penciclovir concentration exceeded the concentration shown to have in vitro efficacy against feline herpesvirus (FHV-1) (0.304 μg/mL) in about half of samples collected. Oral administration of 40 mg of famciclovir/kg to cats resulted in a tear penciclovir concentration-time profile that approximated the plasma penciclovir concentration-time profile and frequently achieved a penciclovir concentration at the ocular surface likely to be effective against FHV-1.

Feline panleukopenia virus, feline herpesvirus-1 and feline calicivirus antibody responses in seronegative specific pathogen-free kittens after parenteral administration of an inactivated FVRCP vaccine or a modified live FVRCP vaccine.

Two groups of feline panleukopenia (FPV), feline calicivirus (FCV) and feline herpesvirus 1 (FHV-1) seronegative kittens (six cats per group) were administered one of two feline viral rhinotracheitis, calcivirus and panleukopenia (FVRCP) vaccines subcutaneously (one inactivated and one modified live) and the serological responses to each agent were followed over 49 days (days 0, 2, 5, 7, 10, 14, 21, 28, 35, 42, 49). While the kittens administered the modified live FPV vaccine were more likely to seroconvert on day 7 after the first inoculation than kittens administered the inactivated vaccine, all kittens had seroconverted by day 14. In contrast, FHV-1 serological responses were more rapid following administration of the inactivated FVRCP vaccine when compared with the modified live FVRCP vaccine. There were no statistical differences between the serological response rates between the two FVRCP vaccines in regard to FCV.

Effects of maternally-derived antibodies on serologic responses to vaccination in kittens.

The optimal vaccination protocol to induce immunity in kittens with maternal antibodies is unknown. The objective of this study was to determine the effects of maternally-derived antibody (MDA) on serologic responses to vaccination in kittens. Vaccination with a modified live virus (MLV) product was more effective than an inactivated (IA) product at inducing protective antibody titers (PAT) against feline panleukopenia virus (FPV). IA vaccination against feline herpesvirus-1 (FHV) and feline calicivirus (FCV) was more effective in the presence of low MDA than high MDA. Among kittens with low MDA, MLV vaccination against FCV was more effective than IA vaccination. A total of 15%, 44% and 4% of kittens had insufficient titers against FPV, FHV and FCV, respectively, at 17 weeks of age. Serologic response to vaccination of kittens varies based on vaccination type and MDA level. In most situations, MLV vaccination should be utilized and protocols continued beyond 14 weeks of age to optimize response by all kittens.

Evaluation of antiviral and cytotoxic activities of methanolic extract of S. grandiflora (Fabaceae) flowers

ObjectiveTo investigate the cytotoxicity and antiviral activity of methanolic extract of S. grandiflora flowers using different cell lines and viruses. MethodsThe methanolic flower extracts were prepared and evaluated for their antiviral and cytotoxic activities using viruses like herpes simplex-1 and 2, vaccinia, vesicular stomatitis, cox sackie, respiratory syncytical, feline corona, feline herpes, para influenza, reo-1, sindbis and punta toro viruses in different cell lines, like Hel, HeLa, Crandell Reus feline kidney and Vero cell cultures. ResultsAmong the viruses used the extract possessed strongest antiviral activity against herpes simplex 1 and 2, repiratory syncytical, para influenza, reo, sindbis, cox sackie and punta toro viruses that was (EC50=20 μg/mL and 45 μg/mL) and moderate activity for remaining viruses (EC50= 100 μg/mL). The antiviral activities assessed by calculating the selectivity index may be due to the presence of flavonoids in the extracts there by inhibit the virus cell fusion in the early and replication stages. The cytotoxicity effect was evaluated using MTT assay and the results revealed that the extracts exhibited cytotoxicity from the range of 20 to 100 μg/mL. ConclusionsPresent results confirmed that the S. grandiflora used as a good antimicrobial agent in future.

Herpesvirus dermatitis in two cats without facial lesions

Cats with feline herpesvirus (FeHV-1)-associated dermatitis typically present with ulcerative lesions on the rostral muzzle and nasal planum. This report describes FeHV-1 dermatitis in the flank region, in the absence of facial lesions. Clinicians should be aware of this unusual manifestation of FeHV-1 dermatitis to prevent potential misdiagnosis. A 12-year-old male castrated Bengal cat and a 3-year-old male castrated Siamese cat with plaques and ulcers in the flank region are described. Formalin-fixed biopsy samples were obtained from lesional skin. Histopathology and FeHV-1 immunohistochemistry were performed. Each sample had epidermal and follicular necrosis with a dense dermal infiltrate of eosinophils. Few to moderate numbers of intranuclear inclusion bodies were present in keratinocytes. The presence of FeHV-1 in the lesions was confirmed with immunohistochemistry. Feline herpesvirus-associated dermatitis should not be ruled out based on the location of the lesion, because a correct diagnosis is imperative for proper treatment. Future studies to assess the cause of lesions at this unusual site are warranted.

True versus False Parasite Interactions: A Robust Method to Take Risk Factors into Account and Its Application to Feline Viruses

BackgroundMultiple infections are common in natural host populations and interspecific parasite interactions are therefore likely within a host individual. As they may seriously impact the circulation of certain parasites and the emergence and management of infectious diseases, their study is essential. In the field, detecting parasite interactions is rendered difficult by the fact that a large number of co-infected individuals may also be observed when two parasites share common risk factors. To correct for these “false interactions”, methods accounting for parasite risk factors must be used.Methodology/Principal FindingsIn the present paper we propose such a method for presence-absence data (i.e., serology). Our method enables the calculation of the expected frequencies of single and double infected individuals under the independence hypothesis, before comparing them to the observed ones using the chi-square statistic. The method is termed “the corrected chi-square.” Its robustness was compared to a pre-existing method based on logistic regression and the corrected chi-square proved to be much more robust for small sample sizes. Since the logistic regression approach is easier to implement, we propose as a rule of thumb to use the latter when the ratio between the sample size and the number of parameters is above ten. Applied to serological data for four viruses infecting cats, the approach revealed pairwise interactions between the Feline Herpesvirus, Parvovirus and Calicivirus, whereas the infection by FIV, the feline equivalent of HIV, did not modify the risk of infection by any of these viruses.Conclusions/SignificanceThis work therefore points out possible interactions that can be further investigated in experimental conditions and, by providing a user-friendly R program and a tutorial example, offers new opportunities for animal and human epidemiologists to detect interactions of interest in the field, a crucial step in the challenge of multiple infections.

Synthesis, characterization and antiviral evaluation of 1,3-Thiazolidine-4-one derivatives bearing L-Valine side chain

ABSTRACT: 1,3-Thiazolidine-4-ones have been known to possess anti-HIV and anti-HCV activity as they are, respectively, HIV-1 non-nucleoside reverse transcriptase inhibitors and HCV NS5B RNA-dependent RNA-polymerase inhibitors. Some novel 1-[2-(benzoylamino)- 3-methylbutyryl]-4-alkyl/arylalkylthiosemicarbazides, 2-[2-(benzoylamino)-3-methylbutyrylhydrazono]- 3-alkyl-/arylalkyl- 5-non substituted/methyl-1,3-thiazolidinones, were synthesized and evaluated for their antiviral activity. Antiviral activity of the synthesized compounds were screened against various types of viruses (Feline Corona Virus (FIPV), Feline Herpes Virus, HSV-1(KOS), HSV-1(TK-KOS ACVr), HSV-2(G), Vaccinia virus, Vesicular stomatitis virus, Varicella- ZosterVirus TK+VZV, Varicella-ZosterVirus TK-VZV, Cytomegalovirus, Respiratory syncytial virus, Coxsackie B4 virus, Parainfluenza-3 virus, Reovirus-1, Sindbis virus and Punta Toro virus) in CRFK, HEL, HeLa and Vero cell cultures. Anti-HIV and cytotoxicity data were also obtained with the compounds using the strains HIV-1 (IIIB) and HIV-2 (ROD) in an MT-4/MTT based assay. None of the tested compounds showed antiviral activity at subtoxic concentrations. For all the synthesized compounds anti-HCV NS5B RdRp activity was not observed at the concentration of 100 μM which was the highest concentration tested. KEYWORDS: 4-Thiazolidinones, L-valine, anti-HIV activity, anti-HCV activity.

Isolation and identification of feline calicivirus and feline herpesvirus in Southern Brazil

Feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1) are the two primary causes of upper respiratory tract disease in cats. The aim of this study was to demonstrate the distribution of FCV and FHV-1 among the feline population of several counties in Rio Grande do Sul State, Brazil. To this end, conjunctival and nasal swabs were collected from 302 cats from different locations, including households, breeding catteries, veterinary clinics, animal hospitals and experimental research facilities. The samples were collected between July 2006 to June 2009. The virus isolation was performed in CRFK cells and, subsequently, the identification was confirmed by PCR. FCV, FHV-1, or both were isolated from 55 cats from 28 different locations. FCV alone was isolated from 52.7% (29/55) of the animals that tested positively, FHV-1 alone was isolated from 38.2% (21/55) of the animals that tested positively, and co-infection were detected in 9.1% (5/55) of the animals that tested positively. Virus detection was more prevalent in cats that were less than 1 year old, among animals that shared a living space with other cats, and females. FCV and FHV-1 were isolated from vaccinated cats. In addition, both viruses were isolated from cats that showed no signs of disease. The results suggest that a carrier state is common for both viruses in the evaluated population. A search for other causes of respiratory disease in that population is necessary; and further studies relating to the molecular characterization of viruses and vaccine efficacy are also necessary.

Prevalence of Herpesvirus Type 1 Conjunctivitis in Domestic Cats in Timiș County, Romania

A survey of feline herpesvirus type 1 (FHV-1) conjunctivitis, in domestic cats fromTimiAŸ County area in Westhern Romania was conducted in between Ianuary and September 2011, andresults were compared the with results in other countries, published by other researchers, investigatedby immunofluorescent antibody assay (IFA). The positive rate of FHV-1 conjunctivitis in domesticcats was 25%. Seroprevalence of FHV-1 in studied domestic cats, with clinical signs was 45%.

Feline calicivirus: a neglected cause of feline ocular surface infections?

To investigate the prevalence of feline calicivirus (FCV) infection in relation to ocular surface lesions in cats with upper respiratory tract diseases (URTD). Ninety-nine cats with ocular surface infection and symptoms or recent history of URTD were examined at various rescue shelters and hospitals. A complete general and ophthalmic examination was performed including Schirmer tear test, slit-lamp biomicroscopy, fluorescein and lissamine green staining. Clinical and ocular symptoms were scored and recorded. Conjunctival samples were collected using a cytobrush, and nucleic acid extraction using RT-PCR was carried out to analyze for the presence of various infectious agents. RT-PCR detected either FCV, feline herpes virus type 1 (FHV-1), Chlamydophila felis or Mycoplasma spp. in 63/99 samples. 30/63 samples were positive for FCV, 23/63 for C. felis, 21/63 for Mycoplasma spp., and 16/63 for FHV-1. Out of the 30 FCV-positive samples, 11 were positive only for FCV and in 19 samples FCV was seen in combination with other agents. FCV infection was highest in animals examined at the rescue centers and in the age group of 0-2 months. Erosive conjunctivitis was an important ocular finding. Oral ulcers were detected in all FCV-infected cats. Results indicate that FCV is highly prevalent in cats with URTD either as a sole infectious agent or in combination with other pathogens and therefore is a potential cause for ocular surface lesions during the URTD.

Feline herpesvirus 1 infections in a domestic cat population in Ahvaz, Iran.

Summary Feline herpesvirus 1 (FeHV-1) and feline calicivirus (FCV), associated with upper respiratory tract disease, are highly prevalent in cats worldwide. With the aim of investigating the importance of FeHV-1 in a population of cats, samples were taken in a hospital in Ahvaz, south-west Iran, between June 2007 and June 2008. Oropharyngeal, nasal and ocular swabs were collected from 65 domestic cats, including 52 stray and 13 household animals and were tested for the presence of FeHV-1 DNA by polymerase chain reaction (PCR). The overall prevalence rate of FeHV-1 was 35.38%. There was a statistically significant association between the prevalence rate of FeHV-1 and the presence of respiratory signs. High prevalence of FeHV-1 infection strengthens the importance of applying hygienic and preventive measures in cats in the study area.

The antiviral activity of six South African plants traditionally used against infections in ethnoveterinary medicine

Viral infections remain a major threat to humans and animals and there is a crucial need for new antiviral agents especially with the development of resistant viruses. The hexane, dichloromethane, acetone and methanol extracts of six plant species selected for their traditional use against infections were tested for in vitro antiviral activity against canine distemper virus (CDV), canine parainfluenza virus-2 (CPIV-2), feline herpesvirus-1 (FHV-1) and lumpy skin disease virus (LSDV). All extracts were tested for their cytotoxicity using a colorimetric tetrazolium-based (MTT) assay and were tested for antiviral efficacy at concentrations below CC50 values on the various cell types used in this study. The antiviral activity of extracts was tested using virucidal and attachment assays. In the virucidal assay, extracts were incubated with virus prior to infection. The most potent inhibition was observed with the acetone and methanol extracts of Podocarpus henkelii against CDV and LSDV, which inhibited replication of the viruses by >75% at 3μg/ml with selectivity index (SI) values ranging between 12 and 45. Excellent activity was also found with the hexane extracts of Plumbago zeylanica and Carissa edulis against CDV, with the extracts reducing viral-induced CPE by 50% and 75% respectively. The hexane extract of C. edulis had moderate activity against FHV-1 with EC50<70μg/ml and SI value <2. Only the acetone extract of P. henkelii moderately inhibited replication of LSD virus in the attachment assay, with low activity in other extracts. Of the four extracts with significant antiviral activity, two were prepared from P. henkelii. Therefore, future work will focus on isolating and characterizing the substance(s) responsible for bioactivity in extracts of this species.

The in vitro effects of proxymetacaine, fluorescein, and fusidic acid on real‐time PCR assays used for the diagnosis of Feline herpesvirus 1 and Chlamydophila felis infections

To investigate the possible inhibition of qPCR assays used for the diagnosis of ocular infections in cats by proxymetacaine, fluorescein, and fusidic acid, which are commonly used in veterinary ophthalmology. Fluorescein, proxymetacaine, and fusidic acid were tested for possible inhibition of a triplex qPCR assay designed to detect Chlamydophila felis, Feline herpesvirus 1 (FHV-1), and the feline 28S ribosomal DNA (28S rDNA) gene by comparing threshold cycle (C(t) ) values of samples with and without the three products. A second experiment was carried out to measure the effects of various dilutions of fusidic acid. No statistically significant differences were detected between the C. felis, FHV-1, and 28S rDNA C(t) values with and without proxymetacaine or fluorescein. However, there was a statistically significant increase in FHV-1 (P < 0.01), C. felis (P < 0.01), and 28S rDNA (P < 0.05) C(t) values when fusidic acid was used. When dilutions of fusidic acid were tested, the results revealed that only the 1:2 dilution caused a statistically significant increase (P < 0.01) in the FHV-1 Ct values. Proxymetacaine and fluorescein did not interfere with our qPCR assays for the detection of C. felis and FHV-1. The presence of fusidic acid caused a small inhibitory effect of doubtful clinical significance. In vivo studies are required to establish the clinical relevance of this study and to confirm our findings.

Detection of protective antibody titers against feline panleukopenia virus, feline herpesvirus-1, and feline calicivirus in shelter cats using a point-of-care ELISA

Serum antibody titers are a useful measurement of protection against infection (feline panleukopenia virus [FPV]) or clinical disease (feline herpesvirus-1 [FHV] and feline calicivirus [FCV]), and their determination has been recommended as part of disease outbreak management in animal shelters. The objective of this study was to determine the sensitivity, specificity, and inter-observer and inter-assay agreement of two semi-quantitative point-of-care assays for the detection of protective antibody titers (PAT) against FPV, FHV and FCV in shelter cats. Low sensitivity for FPV antibodies (28%) rendered a canine point-of-care assay inappropriate for use in cats. The feline point-of-care assay also had low sensitivity (49%) and low negative predictive value (74%) for FPV PAT detection, but was highly accurate in the assessment of FHV and FCV PAT. Improvements in accuracy and repeatability of FPV PAT determination could make this tool a valuable component of a disease outbreak response in animal shelters.