Molecular epidemiology of feline bordetellosis in two animal shelters in California, USA

Effect of carbohydrates on the adhesion of Bordetella bronchiseptica to the respiratory epithelium in rabbits

This study proposes an ecological approach for preventing respiratory tract infections caused by Bordetella bronchiseptica in mammals using a mixture of carbohydrates. In an in vivo study, 51-day-old New Zealand rabbits were treated with a solution containing 1 × 107 CFUs of B. bronchiseptica and 250 μg of one of the following carbohydrates: N acetylglucosamine (GlcNAc), N acetylgalactosamine (GalNAc), alpha methyl mannose (AmeMan), alpha methyl glucose (AmeGlc) and sialic acid (Neu5AC). Positive (B. bronchiseptica) and negative (Physiological Saline Solution (PSS)) controls were included. Animals treated with GlcNAc or AmeGlc showed no clinical signs of infection and exhibited a significant reduction (p < 0.05) in the severity of microscopic lesions evaluated in the nasal cavity and lung compared with the positive controls. Additionally, the presence of bacteria was not detected through microbiological isolation or PCR in the lungs of animals treated with these sugars. Use of a mixture of GlcNAc and AmeGlc resulted in greater inhibition of microscopic lesions, with a significant reduction (p < 0.05) in the severity of these lesions compared to the results obtained using individual sugars. Furthermore, the bacterium was not detected through microbiological isolation, Polymerase Chain Reaction (PCR) or indirect immunoperoxidase (IIP) in this group.

A review of evidence-based management of infectious ocular surface disease in shelter-housed domestic cats

Infectious ocular surface disease (IOSD) is a common problem in shelter-housed domestic cats and has a widespread negative impact on animal welfare. While the common etiological agents are well-described, addressing IOSD in large groups of animals presents a management challenge to the clinician and logistical challenges to shelter employees. Treatments, diagnostics, and prevention strategies that are effective in privately owned or experimental animals may be impractical or ineffective in the shelter environment. This review article focuses on the relative prevalence of etiological agents in feline IOSD, practical diagnostic testing protocols, prevention strategies, and treatment of IOSD in shelter-housed cats. Discrepancies between experimental laboratory-based studies and clinical trials assessing therapeutics for treatment of feline herpes virus are highlighted. Further high-quality clinical trials are necessary to determine optimal preventative and therapeutic protocols for IOSD in shelter-housed cats.

Outbreak management of multidrug-resistant Bordetella bronchiseptica in 16 shelter-housed cats

CASE SERIES SUMMARY

This case series describes an outbreak of multidrug-resistant (MDR) Bordetella bronchiseptica in 16 shelter-housed cats with infectious respiratory disease. Four cats presented with acute dyspnea on the same day, each with a history of previous upper respiratory disease that had resolved with treatment. Early diagnostic testing and culture and sensitivity allowed for targeted antimicrobial therapy and environmental interventions. A case definition based on exposure and clinical signs identified 12 additional presumptive cases, including the likely index case. Comprehensive outbreak management included diagnostic testing, risk assessment, vaccination, use of isolation and quarantine, increased surveillance and review of biosecurity practices. The outbreak resolved in 26 days.

RELEVANCE AND NOVEL INFORMATION

Management of an MDR B bronchiseptica outbreak in shelter-housed cats has not been previously described. Along with standard population and environmental measures, early and appropriate use of necropsy, PCR and bacterial culture allowed rapid and appropriate use of effective, second-line antibiotics. Shelters are resource-challenged population centers. Veterinarians working in animal shelters can play an important role in helping to develop cost-efficient and effective antimicrobial stewardship practices for companion animal settings. Outbreak management expertise and funding for diagnostic testing, as well as application of the principles of antimicrobial stewardship, are essential components of shelter medicine practice.

Antimicrobial resistance profiles of bacteria associated with lower respiratory tract infections in cats and dogs in England

BACKGROUND

Bacterial lower respiratory tract infections (bLRTIs) are common and potentially life threatening in cats and dogs. Antibiotic treatment is often initiated before the diagnosis of bLRTI; therefore improved knowledge of the aetiology and antibiotic susceptibility patterns of these infections is essential to inform empiric antibiotic choices.

METHODS

A retrospective study of microbiological, cytological results and their drug susceptibilities from lower respiratory samples (n = 1989) processed in a UK commercial laboratory between 2002 and 2012 was carried out.

RESULTS

Thirty-nine per cent of feline samples and 50% of canine samples were positive for bacterial growth with most yielding a single organism (72 % and 69%, respectively). Bordetella bronchiseptica (20.2% from dogs and 2.3% from cats), Pasteurella spp. (23.2%, 31.8%), E. coli (16.2%, 13.6%) and Pseudomonas spp. (11.1%, 11.4%) were most frequently isolated from cytologically positive samples which contained intracellular bacteria (10%, 14%). Amoxycillin-clavulanate, cephalothin, cefovecin, oxytetracycline and trimethoprim/sulfamethoxazole showed modest in vitro activity against E. coli from dogs (approximately 70% susceptibility). Pseudomonas spp. were resistant to enrofloxacin (50%), ticarcillin (25%) and marbofloxacin (13%) but showed lower or zero resistance to aminoglycosides (approximately 7%) and ciprofloxacin (0%). Multi drug resistance (acquired resistance to three or more antimicrobial drug classes) was particularly common among E. coli isolates, with 23% from feline samples and 43% from canine samples.

CONCLUSION

Resistance to certain first-choice antibiotics was detected in bLRTIs highlighting the need for continued monitoring and sound evidence to inform decision-making in the management of these infections.

A retrospective study on the presence of selected infectious agents in lung samples of cats with pneumonia

The causative role of some infectious agents found in cases of feline pneumonia is under debate, because they are also part of the physiological microbiota of the respiratory tract of healthy animals. In this retrospective study, archived formalin-fixed and paraffin-wax-embedded lung samples of 69 severe and lethal cases of pneumonia in cats were examined by immunohistochemistry (IHC) for the detection of nine selected infectious agents: Pasteurella multocida, Bordetella bronchiseptica, Mycoplasma felis, M. gateae, Chlamydia felis, feline herpesvirus type 1, feline coronavirus, canine distemper virus, and Toxoplasma gondii. The intention was to elucidate their immediate involvement in pneumonia formation. Due to the cross-reactivity of the applied antibodies, a species-specific polymerase chain reaction (PCR) for both targeted Mycoplasma species was applied additionally. In the 42 cases (60.9%) positive for at least one pathogen, several agents were present in a high proportion of the samples (P. multocida - 34.8%, B. bronchiseptica - 29.0%), while others were present in a moderate (feline herpesvirus type 1 - 18.8%, M. gateae - 13.0%, M. felis - 10.1%) or low percentage (T. gondii - 1.4%). All samples were negative for C. felis, feline coronavirus and canine distemper virus. Mixed infections of up to four pathogens were more frequent than single infections. Mycoplasma preferably colonised lung tissue damaged by other pathogens because they never occurred as single infections. Pasteurella multocida, B. bronchiseptica, M. felis, feline herpesvirus type 1 and T. gondii showed abundant replication within lung lesions, thus suggesting a prominent role in pneumonia formation.

Aetiology of Canine Infectious Respiratory Disease Complex and Prevalence of its Pathogens in Europe

The canine infectious respiratory disease complex (CIRDC) is an endemic worldwide syndrome involving multiple viral and bacterial pathogens. Traditionally, Bordetella bronchiseptica (Bb), canine adenovirus type 2 (CAV-2), canine distemper virus (CDV), canine herpesvirus (CHV) and canine parainfluenza virus (CPiV) were considered the major causative agents. Lately, new pathogens have been implicated in the development of CIRDC, namely canine influenza virus (CIV), canine respiratory coronavirus (CRCoV), canine pneumovirus (CnPnV), Mycoplasma cynos and Streptococcus equi subspecies zooepidemicus. To better understand the role of the different pathogens in the development of CIRDC and their epidemiological relevance in Europe, prevalence data were collected from peer-reviewed publications and summarized. Evidence of exposure to Bb is frequently found in healthy and diseased dogs and client-owned dogs are as likely to be infected as kennelled dogs. Co-infections with viral pathogens are common. The findings confirm that Bb is an important cause of CIRDC in Europe. CAV-2 and CDV recovery rates from healthy and diseased dogs are low and the most likely explanation for this is control through vaccination. Seroconversion to CHV can be demonstrated following CIRDC outbreaks and CHV has been detected in the lower respiratory tract of diseased dogs. There is some evidence that CHV is not a primary cause of CIRDC, but opportunistically re-activates at the time of infection and exacerbates the disease. The currently available data suggest that CIV is, at present, neither a prevalent nor a significant pathogen in Europe. CPiV remains an important pathogen in CIRDC and facilitates co-infection with other viral and bacterial pathogens. CnPnV and CRCoV are important new elements in the aetiology of CIRDC and spread particularly well in multi-dog establishments. M. cynos is common in Europe and is more likely to occur in younger and kennelled dogs. This organism is frequently found together with other CIRDC pathogens and is significantly associated with more severe respiratory signs. S. zooepidemicus infection is not common and appears to be a particular problem in kennels. Protective immunity against respiratory diseases is rarely complete, and generally only a reduction in clinical signs and excretion of pathogen can be achieved through vaccination. However, even vaccines that only reduce and do not prevent infection carry epidemiological advantages. They reduce spread, increase herd immunity and decrease usage of antimicrobials. Recommending vaccination of dogs against pathogens of CIRDC will directly provide epidemiological advantages to the population and the individual dog.

Pharmacokinetics of the amoxicillin-clavulanic acid combination after intravenous and oral administration in cats

The pharmacokinetic properties of amoxicillin (AMX) and clavulanic acid (CLV) were studied in healthy cats following single intravenous and oral dosage of 10 mg/kg of AMX and 2.5 mg/kg of CLV. The drug concentrations in plasma were determined by a high-performance liquid chromatographic-tandem mass spectrometry (LC-MS-MS) method validated for canine plasma and further subjected to noncompartmental analysis. After intravenous injection, no significant difference (p > 0.05) was found in the volume of distribution of these two compounds. In addition, AMX and CLV were both rapidly eliminated from plasma with a clearance of 0.453 and 0.921 L hr^-1  kg^-1 , respectively; however, a quicker elimination was observed for CLV (p < 0.01). After oral administration, both drugs were characterized by rapid absorption with an absorption half-life of 1.10 and 0.70 hr for AMX and CLV, respectively. Significant differences were observed between their absorption rates (p < 0.05). However, the oral bioavailabilities of AMX and CLV (75.57% and 98.15%, respectively) were not statistically different (p > 0.05). A total intravenous or oral dose at 12.5 mg/kg of AMX and CLV (4:1) is predicted to be effective for treating those bacterial species isolated from cats with a minimum inhibitory concentration (MIC) of ≤0.25 μg/ml for 12 hr, based on a time above the MIC (T > MIC) of 40%.

Epidemiological Evaluation of Dogs Rescued in the Fukushima Prefecture Following the Great East Japan Earthquakes of 2011

IntroductionDogs left behind in the restricted area by the Great East Japan Earthquakes of 2011 (Fukushima Prefecture, Japan) were initially rescued at a temporary first response shelter under chaotic conditions: poor housing and husbandry was maintained by unfamiliar/untrained staff, and lack of exercise was associated with deterioration of the mental and physical health of the impounded dogs. The objectives of this study were to report characteristics, disposition, and health status of dogs rescued in the Fukushima Prefecture, and to perform a retrospective epidemiological evaluation of factors associated with disposition and disease incidence at shelters.ProblemsThe problems addressed in this study were shelter-related health issues at the first response shelter and reasons for retained adoption at the secondary shelter that caused delayed closure of the shelter.

METHODS

A retrospective cohort study was performed with all dogs that were rescued from the restricted area in the Fukushima Prefecture. Kaplan-Meier time-to-event analysis was performed to estimate the median days to outcomes. A chi-square test of homogeneity was used to determine whether ownership status was associated with breed. Cox proportional hazards regression models were used to assess the association between time-to-adoption with ownership status, age, sex, and breed, the association between time to onset of diarrhea with age and breed, and between duration of diarrheic symptoms with the number of antibiotics and the number of medications.

RESULTS

Five-hundred and twenty-nine dogs were admitted to the Ihno and Miharu shelters (Fukushima Prefecture), including 179 that had detailed medical records. Seventy-six percent of dogs were mixed breed. Twenty-six percent of dogs had verified ownership, and almost 16% of dogs were reclaimed by their owners. Sixty-six percent of dogs developed diarrhea, and 17 different antibiotics were used to treat it. Using three or more different antibiotics was associated with prolonged signs of diarrhea. Dogs with verified ownership took longer for adoption than those without verified ownership. Breed and sex were not significantly associated with time to adoption. Age was associated with prolonged time to adoption.

CONCLUSION

To improve the welfare of dogs in disasters, responsible owner education, a well-organized registered volunteer training program for care of animals at shelters, proper disease management protocols, and enrichment strategies to prevent stress and disease in shelter setting are essential. TanakaA, Martinez-LopezB, KassP. Epidemiological evaluation of dogs rescued in the Fukushima Prefecture following the Great East Japan Earthquakes of 2011. Prehosp Disaster Med. 2018;33(5):478-583.

Epidemiological evaluation of cat health at a first-response animal shelter in Fukushima, following the Great East Japan Earthquakes of 2011

The Great East Japan Earthquakes of March 11, 2011 caused immense harm to the community and subsequent nuclear accident in Fukushima Prefecture extended the damage. Local residents were forced to evacuated without pets and the left behind animals were rescued from the restricted zone one month later. Unplanned animal rescue and unregulated sheltering caused secondary damage to animals such as disease epidemics at impounded animal shelter. The purpose of this study was to retrospectively evaluate the incidence of upper respiratory infection (URI) and diarrhea in cats at the first response animal shelter in Fukushima, and investigate factors affecting the duration of disease and determinants of treatments performed. Eighty percent and 59% of impounded cats developed URI, 71% and 54% of cats developed diarrhea, and 91% and 83% of cats had at least one disease in 2011 and 2012, respectively. Uses of multiple drug administration (more than five drugs) was associated with prolonged URI and diarrhea. Multiple antibiotics, antihistamines, interferon, and steroids were associated with relapse of and prolonged URI. Developing a standardized treatment protocol for commonly observed diseases at Japanese animal shelters to prevent and control diseases, to promote animal welfare, and protect public health in the face of future disasters is overdue.

Epidemiological evaluation of cats rescued at a secondary emergency animal shelter in Miharu, Fukushima, after the Great East Japan Earthquakes

The aims of this research were to report characteristics of rescued cats at a secondary emergency animal shelter in Fukushima prefecture, Japan, and evaluate how adoptability, stress level, upper respiratory infection (URI) syndrome incidence, and URI pathogen prevalence were associated with the cat's shelter intake source and shelter characteristics. All cats admitted to the Miharu shelter, Fukushima Prefecture from 2012 to 2014 were included in the study. The results demonstrate that in situ corticosteroid and antibiotic use were associated with cats subsequently developing upper respiratory infections (URI). Disease and cat behavior were unassociated with adoption. Cats in group housing had lower stress metrics than cats individually housed. Prevalences of URI pathogens exceeded 80%, but symptomatic cats were uncommon. Environmental enrichment and stress reduction strategies are important in controlling URI and reducing the need for corticosteroids and antibiotics in shelters. Preemptive protocols are important in preventing shelter admission of cats during disasters.

Prevalence of respiratory pathogens detected in dogs with kennel cough in Poland

Kennel cough is a multifactorial disease occurring all over the world; however, its epidemiology is still not fully understood. To the authors’ knowledge, no studies monitoring the occurrence of infectious agents responsible for kennel cough have been carried out in Poland. Therefore, the objective of our study was to determine which of the four pathogens most frequently isolated in other countries are predominant in north-eastern Poland. Swabs from the upper respiratory tract and tracheal lavage fluids from dogs (n = 40) exhibiting symptoms of this disease were analysed. Canine herpesvirus, canine parainfluenza virus, canine adenovirus type 2 andBordetella bronchisepticawere identified by polymerase chain reaction. At least one of the above-listed infectious agents was found in all dogs. The predominant pathogen within the area under our study, both in mono- and co-infections, was canine herpesvirus (32/40), whereas canine adenovirus type 2 occurred least frequently (4/40). The effectiveness of detection of selected pathogens from both types of study material was also compared. Tracheal lavage fluid was more suitable for the isolation of canine herpes virus, canine parainfluenza virus, andBordetella bronchiseptica. Swabs from the upper respiratory tract were more suitable for the isolation of canine adenovirus type 2.

Epidemiologic evaluation of multiple respiratory pathogens in cats in animal shelters

Upper respiratory tract infection (URI) propagates readily within cats in shelters and often results in euthanasia of affected cats. In a case-control evaluation of 573 cats in eight shelters in California in 2001 and 2002, the prevalence of feline calicivirus (FCV) was from 13 to 36%, feline herpesvirus (FHV) was from 3 to 38%, and prevalence of Bordetella bronchiseptica, Chlamydophila felis, and Mycoplasma species was from 2 to 14%. Cats with URI tended to be housed in isolation, dehydrated, and younger than cats without URI, and infected with FHV, Mycoplasma species, FCV, or C felis. Shelters differed in the prevalence of pathogens and many cats appeared positive for infection after about 1 week of sheltering. It is helpful for shelters to understand the risk factors associated with URI in order to evaluate the costs and benefits of treatment and improve their procedures to decrease the incidence of URI within their facilities. Antiherpetics and antimycoplasmal drugs may be beneficial for individual animal care. Results document the utility of comprehensive URI surveillance and herd management for specific pathogens typical in that shelter.

Comparison of ribotyping and sequence-based typing for discriminating among isolates of Bordetella bronchiseptica

PvuII ribotyping and MLST are each highly discriminatory methods for genotyping Bordetella bronchiseptica, but a direct comparison between these approaches has not been undertaken. The goal of this study was to directly compare the discriminatory power of PvuII ribotyping and MLST, using a single set of geographically and genetically diverse strains, and to determine whether subtyping based on repeat region sequences of the pertactin gene (prn) provides additional resolution. One hundred twenty-two isolates were analyzed, representing 11 mammalian or avian hosts, sourced from the United States, Europe, Israel and Australia. Thirty-two ribotype patterns were identified; one isolate could not be typed. In comparison, all isolates were typeable by MLST and a total of 30 sequence types was identified. An analysis based on Simpson's Index of Diversity (SID) revealed that ribotyping and MLST are nearly equally discriminatory, with SIDs of 0.920 for ribotyping and 0.919 for MLST. Nonetheless, for ten ribotypes and eight MLST sequence types, the alternative method discriminates among isolates that otherwise type identically. Pairing prn repeat region typing with ribotyping yielded 54 genotypes and increased the SID to 0.954. Repeat region typing combined with MLST resulted in 47 genotypes and an SID of 0.944. Given the technical and practical advantages of MLST over ribotyping, and the nominal difference in their SIDs, we conclude MLST is the preferred primary typing tool. We recommend the combination of MLST and prn repeat region typing as a high-resolution, objective and standardized approach valuable for investigating the population structure and epidemiology of B. bronchiseptica.

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

Background

Cats 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.

Results

Oropharyngeal, 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).

Conclusions

FCV 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 material

The online version of this article (doi:10.1186/s12917-015-0595-2) contains supplementary material, which is available to authorized users.

How well do vaccines for Bordetella bronchiseptica work in dogs? A critical review of the literature 1977-2014

Bordetella bronchiseptica (Bb) has long been causally associated with respiratory disease in dogs. Parenteral and intranasal vaccines for this pathogen have been in common use since their development in the late 1970s and early 1980s and recently a commercial oral Bb vaccine has become available. Overall, the literature (comprising experimental infection models and field studies) documents the efficacy of these vaccines in stimulating disease-sparing mucosal and systemic immune responses that can be associated with reduced growth of Bb in vivo. However, many of the published studies are limited by flaws in experimental design, most notably a failure to consider the biological and statistical implications of the 'pen effect'. Many questions related to the longevity of vaccine induced immunity against Bb and the impact of natural exposure on herd immunity remain unanswered.

Feline respiratory disease complex

Feline respiratory disease complex (FRDC) refers to the characteristic acute presentation of a contagious respiratory or ocular disease caused by one or multiple pathogens. Environmental and host factors impact the transmission, clinical presentation, preventive strategy, and treatment of affected cats. The FRDC is especially problematic in settings where large numbers of cats cohabit, including animal shelters, catteries, and semi-feral colonies. Although elimination of FRDC is an unrealistic goal, improved understanding can lead to strategies to minimize disease impact.

Lower respiratory tract infections in cats: reaching beyond empirical therapy

PRACTICAL RELEVANCE

Lower respiratory tract infections (LRTIs) in cats can be due to bacteria, parasites, fungi and viruses. This review details the practical investigation of these infections and highlights specific therapy where possible. The aim is to avoid the all-too-frequent temptation in practice to treat cats with lower respiratory tract signs empirically for feline bronchial disease (FBD)/asthma. This is potentially hazardous as immunosuppressive therapy for FBD/asthma could exacerbate disease due to a LRTI. Empirical treatment of suspected LRTI is also difficult to recommend given the wide range of potential pathogens.

CLINICAL CHALLENGES

Making a clinical ante-mortem diagnosis of LRTI in a cat can be challenging. Consistent historical, clinical, haematological and radiographic abnormalities are often lacking and findings may be non-specific. Astute clinical acumen, thorough investigation and high quality laboratory analysis are usually required for a diagnosis. Bronchoalveolar lavage, if feasible, and tests for lungworm should be routine in cats with lower respiratory tract signs. Lung fine needle aspiration may be useful in cases of diffuse or nodular pulmonary disease. Histopathology is rarely employed in ante-mortem investigations.

EVIDENCE BASE

The authors have reviewed a substantial body of literature to provide information on many of the reported bacterial, parasitic, fungal and viral pathogens, including some that occur in Asia. Attention has been given to specific therapy for each pathogen, with evidence-based comments when there is a deviation from routine recommendations.

Bordetella evades the host immune system by inducing IL-10 through a type III effector, BopN

The inflammatory response is one of several host alert mechanisms that recruit neutrophils from the circulation to the area of infection. We demonstrate that Bordetella, a bacterial pathogen, exploits an antiinflammatory cytokine, interleukin-10 (IL-10), to evade the host immune system. We identified a Bordetella effector, BopN, that is translocated into the host cell via the type III secretion system, where it induces enhanced production of IL-10. Interestingly, the BopN effector translocates itself into the nucleus and is involved in the down-regulation of mitogen-activated protein kinases. Using pharmacological blockade, we demonstrated that BopN-induced IL-10 production is mediated, at least in part, by its ability to block the extracellular signal-regulated kinase pathway. We also showed that BopN blocks nuclear translocation of nuclear factor κB p65 (NF-κBp65) but, in contrast, promotes nuclear translocation of NF-κBp50. A BopN-deficient strain was unable to induce IL-10 production in mice, resulting in the elimination of bacteria via neutrophil infiltration into the pulmonary alveoli. Furthermore, IL-10–deficient mice effectively eliminated wild-type as well as BopN mutant bacteria. Thus, Bordetella exploits BopN as a stealth strategy to shut off the host inflammatory reaction. These results explain the ability of Bordetella species to avoid induction of the inflammatory response.

Evaluation of pradofloxacin for the treatment of feline rhinitis

Forty humane society cats with suspected bacterial upper respiratory infections (URIs) were studied in order to compare amoxycillin and pradofloxacin for treatment of rhinitis and describe common pathogens. Nasal discharges were collected prior to random placement into one of three treatment groups. Cats failing to initially respond were crossed to the alternate drug. Drug toxicity was not noted. The organisms most frequently isolated or amplified pre-treatment were feline herpesvirus-1 (75%), Mycoplasma species (62.5%), Bordetella species (47.5%), Staphylococcus species (12.5%) and Streptococcus species (10.0%). No differences in clinical scores between groups over time were noted. Overall response rates for amoxycillin at 22 mg/kg, q12 h for seven doses (10/15 cats; 67%), pradofloxacin at 5 mg/kg, q24 h for seven doses (11/13 cats; 85%), and pradofloxacin at 10 mg/kg, q24 h for seven doses (11/12 cats; 92%) were not statistically significant. Results suggest that pradofloxacin can be a safe, efficacious therapy for some cats with suspected bacterial URI.

Effect of vaccination on parvovirus antigen testing in kittens

OBJECTIVE

To determine the frequency and duration of feline panleukopenia virus (FPV) vaccine-induced interference with fecal parvovirus diagnostic testing in cats.

DESIGN

Prospective controlled study.

ANIMALS

Sixty-four 8- to 10-week-old specific-pathogen-free kittens.

PROCEDURES

Kittens were inoculated once with 1 of 8 commercial multivalent vaccines containing modified-live virus (MLV) or inactivated FPV by the SC or intranasal routes. Feces were tested for parvovirus antigen immediately prior to vaccination, then daily for 14 days with 3 tests designed for detection of canine parvovirus. Serum anti-FPV antibody titers were determined by use of hemagglutination inhibition prior to vaccination and 14 days later.

RESULTS

All fecal parvovirus test results were negative prior to vaccination. After vaccination, 1 kitten had positive test results with test 1, 4 kittens had positive results with test 2, and 13 kittens had positive results with test 3. Only 1 kitten had positive results with all 3 tests, and only 2 of those tests were subjectively considered to have strongly positive results. At 14 days after vaccination, 31% of kittens receiving inactivated vaccines had protective FPV titers, whereas 85% of kittens receiving MLV vaccines had protective titers.

CONCLUSIONS AND CLINICAL RELEVANCE

Animal shelter veterinarians should select fecal tests for parvovirus detection that have high sensitivity for FPV and low frequency of vaccine-related test interference. Positive parvovirus test results should be interpreted in light of clinical signs, vaccination history, and results of confirmatory testing. Despite the possibility of test interference, the benefit provided by universal MLV FPV vaccination of cats in high-risk environments such as shelters outweighs the impact on diagnostic test accuracy.

The 2006 American Association of Feline Practitioners Feline Vaccine Advisory Panel Report

Vaccination is a medical procedure, and the decision to vaccinate should be based on a risk-based assessment for each cat and each vaccine.

BopC is a novel type III effector secreted by Bordetella bronchiseptica and has a critical role in type III-dependent necrotic cell death

In Bordetella bronchiseptica, the functional type III secretion system (TTSS) is required for the induction of necrotic cell death in infected mammalian cells. To identify the factor(s) involved in necrotic cell death, type III-secreted proteins from B. bronchiseptica were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and electrospray ionization tandem mass spectrometry. We identified a 69-kDa secreted protein designated BopC. The gene encoding BopC is located outside of the TTSS locus and is also highly conserved in both Bordetella parapertussis and Bordetella pertussis. The results of a lactate dehydrogenase release assay and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assay demonstrated that BopC is required for necrotic cell death. It has been reported that tyrosine-phosphorylated proteins (PY) of host cells are dephosphorylated during B. bronchiseptica infection in a TTSS-dependent manner. We found that BopC is also involved in PY dephosphorylation in infected host cells. It appears that the necrotic cell death triggered by BopC occurs prior to the PY reduction in host cells, because Bordetella-induced cell death was not affected even in the presence of a dephosphorylation inhibitor. Furthermore, a translocation assay showed that the signal sequence for both secretion into culture supernatant and translocation into the host cell is located in 48 amino acid residues of the BopC N terminus. This report reveals for the first time that a novel type III effector, BopC, is required for the induction of necrotic cell death during Bordetella infection.

Assessment of infectious organisms associated with chronic rhinosinusitis in cats

OBJECTIVE

To determine detection rates for feline herpesvirus type 1 (FHV-1), Mycoplasma spp, fungi, and bacteria in flush samples and biopsy specimens from the nasal cavities of cats with and without chronic rhinosinusitis (CRS).

DESIGN

Prospective study.

ANIMALS

10 CRS-affected cats and 7 cats without signs of respiratory tract disease.

PROCEDURES

Nasal flush samples and biopsy specimens were collected from all cats for bacterial (aerobic and anaerobic), fungal, and mycoplasmal cultures; additional biopsy specimens were collected for virus isolation and polymerase chain reaction (PCR) assay (to detect FHV-1 DNA).

RESULTS

Aerobic bacteria were detected in flush samples from 5 of 7 control cats; culture of flush samples from CRS-affected cats yielded aerobic bacteria (9/10 cats), anaerobic bacteria (3/10), and Mycoplasma spp (2/10). No fungal organisms were isolated from any cat. Potential pathogens were isolated significantly more often from CRS-affected cats than from control cats. Bacterial culture of biopsy specimens yielded aerobic bacteria (2/7 control cats and 4/10 CRS-affected cats) and anaerobic bacteria (2/10 CRS-affected cats). Although FHV-1 was not detected in nasal biopsy specimens from control or CRS-affected cats, FHV-1 DNA was detected via PCR assay in specimens from 4 of 7 control cats and 3 of 10 CRS-affected cats.

CONCLUSIONS AND CLINICAL RELEVANCE

Compared with findings in control cats, anaerobic bacteria, Mycoplasma spp, and a variety of potentially pathogenic organisms were detected more commonly in samples from cats with CRS. In both groups, FHV-1 was detected via PCR assay as a nonviable organism or in noncultivable amounts.

Amplified fragment length polymorphism (AFLP) versus randomly amplified polymorphic DNA (RAPD) as new tools for inter- and intra-species differentiation within Bordetella

Automated amplified fragment length polymorphism (AFLP) and randomly amplified polymorphic DNA (RAPD) techniques with fluorescently labelled primers were used to track differences among isolates of the eight known species of the Bordetella genus. Eighty-one representative strains of these species from international and Polish bacterial collections were genotyped according to RAPD protocols using primer 1254 or 1247, and AFLP involving EcoRI/MseI or newly designed SpeI/ApaI restriction/ligation/amplification procedures. By comparing AFLP and RAPD data, it was concluded that the discriminatory power of AFLP is higher in comparison with RAPD for both intra- and inter-species differentiation of isolates of the Bordetella genus. The most precise level of inter-species discrimination and the highest level of intra-species discrimination of the Bordetella isolates of the eight species were observed in the AFLP EcoRI/MseI and SpeI/ApaI sets, respectively. Both techniques might provide alternative tools for the identification of Bordetella at the genomic species and strain levels, and thus may be valuable in human and veterinary diagnostics as well as in epidemiology. By applying the AFLP technique presented in this article, more precise data on the emergence of newly acquired and/or on expanded clones and transmission routes of isolates of the Bordetella genus in the human and animal environments might be obtained.

A placebo-controlled trial of two intranasal vaccines to prevent tracheobronchitis (kennel cough) in dogs entering a humane shelter

A placebo-controlled field trial was conducted to compare the effectiveness of intranasal (IN) vaccines containing Bordetella bronchiseptica and canine-parainfluenza virus, with (IN-BPA) or without (IN-BP) canine-adenovirus type 2, for prevention of kennel cough at a humane shelter. Dogs were examined on admission to the shelter and those without respiratory signs of disease were assigned daily, on a rotating basis, to receive one of three vaccines. We enrolled 972 healthy dogs. Dogs were monitored for up to 30 days post-vaccination for coughing and other clinical signs of respiratory disease. Thirty-three (10.7%; 95% confidence interval (CI): 7.2, 14.2) dogs in the IN-BP group, 36 (10.2%; 95% CI: 7.0, 13.4) dogs in the IN-BPA group, and 42 (13.5%; 95% CI: 9.7, 17.3) dogs in the IN-P group coughed spontaneously for ≥1 day within 30 days of vaccination (P=0.37). The IN-BP and IN-BPA vaccines were 20.7 and 24.4% effective, respectively, in reducing coughing compared with a placebo vaccine. The strongest prognostic factor for coughing (regardless of vaccine group) was the number of days spent at the shelter, with each additional day increasing the risk of coughing by 3% (95% CI: 0.5, 6.3). The low incidence of coughing in the shelter during this study precluded observation of differences in vaccine effectiveness. No differences in vaccine-associated adverse events (coughing, sneezing, nasal or ocular discharge) were noted during the first 3 days post-administration or thereafter.