Adverse events diagnosed within three days of vaccine administration in dogs

Retrospective evaluation of hypersensitivity reactions and anaphylaxis in dogs (2003-2014): 86 cases

OBJECTIVE

To characterize anaphylactic reactions in dogs, including clinical signs, severity, treatments, prognosis, and estimated incidence. To determine whether glucocorticoids influence clinical recovery and survival.

DESIGN

Retrospective study between January 1, 2003 and April 28, 2014.

SETTING

University teaching hospital.

ANIMALS

Eighty-six dogs treated for a type I hypersensitivity reaction. Nineteen dogs fulfilled the criteria for anaphylaxis, and 67 dogs had mild cutaneous reactions.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The estimated incidence was 0.04% for anaphylaxis and 0.15% for mild hypersensitivity reactions. The female:male ratio (2.3:1) was significantly higher (P = 0.032) compared to our source population (ratio of 1:1.158). Vaccines were the most frequent trigger for anaphylaxis (57.9%) and mild hypersensitivity reactions (28.4%). Seventy-four (86%) dogs had cutaneous signs, and 11 (57.9%) dogs with anaphylaxis had no cutaneous signs reported. Forty-two (48.8%) dogs received both an H1 antagonist and a glucocorticoid, 34 (39.5%) dogs received an H1 antagonist only, and 6 (6.9%) dogs received a glucocorticoid only. The majority of the dogs survived, and 1 was euthanized due to complications. Clinical signs associated with nonsurvival included respiratory signs (P = 0.006), particularly respiratory distress (P < 0.00001) and cyanosis (P < 0.00001), and circulatory shock (P = 0.005). The analysis of the interaction between etiology, clinical signs, treatment, and outcome did not show any association between pairs of variables.

CONCLUSIONS

In the current study, anaphylaxis had a relatively good prognosis, and cutaneous signs were not always present. Based on the present data, the use of glucocorticoids to treat mild type I hypersensitivity reactions and anaphylaxis in dogs was not associated with clinical improvement or survival.

Feline Injection-Site Sarcoma and Other Adverse Reactions to Vaccination in Cats

Vaccine-associated adverse events (VAAEs), including feline injection-site sarcomas (FISSs), occur only rarely but can be severe. Understanding potential VAAEs is an important part of informed owner consent for vaccination. In this review, the European Advisory Board on Cat Diseases (ABCD), a scientifically independent board of feline medicine experts, presents the current knowledge on VAAEs in cats, summarizing the literature and filling the gaps where scientific studies are missing with expert opinion to assist veterinarians in adopting the best vaccination practice. VAAEs are caused by an aberrant innate or adaptive immune reaction, excessive local reactions at the inoculation site, an error in administration, or failure in the manufacturing process. FISS, the most severe VAAE, can develop after vaccinations or injection of other substances. Although the most widely accepted hypothesis is that chronic inflammation triggers malignant transformation, the pathogenesis of FISS is not yet fully understood. No injectable vaccine is risk-free, and therefore, vaccination should be performed as often as necessary, but as infrequently as possible. Vaccines should be brought to room temperature prior to administration and injected at sites in which FISS surgery would likely be curative; the interscapular region should be avoided. Post-vaccinal monitoring is essential.

Clinical assessment of a point-of-care assay to determine protective vaccinal antibody titers to canine viral diseases

Guidelines recommend that dogs are vaccinated for canine distemper virus (CDV), canine parvovirus (CPV), and canine adenovirus (CAV) every 3 years. Alternatively, their antibody titers are measured and vaccines given when titers fall below a protective threshold. In this study, a point-of-care (POC) assay was compared to hemagglutination inhibition (for CPV) and virus neutralization (for CAV and CDV) assays to predict the need for revaccination Ninety-two dogs presented for vaccination were enrolled. The POC assay indicated protective titers against CDV in 79/80, CPV in 89/90, and CAV in 91/91 dogs with reference standard antibody measurements that were over a protective threshold. The sensitivity of the POC assay for to detect protective concentrations of CDV antibodies was 99% (95% confidence interval [CI 95%], 93.3-99.9%). Ten dogs were falsely considered protected against CDV by the POC assay with a specificity of 17% (CI 95%, 3.0-44.8%). The sensitivity of the POC assay for protective concentrations of CPV titers was 99% (CI 95%, 93.9-99.9%). The sensitivity of the POC assay to detect protective concentrations of CAV antibodies was 100% (CI 95%, 95.9-100%). Only classifying high-positive CDV and CPV titers on the POC assay as protective improved assay specificity to 100%, but sensitivity decreased to 51% and 76% respectively. This POC assay had a high sensitivity for the detection of protective antibody titers; however, some dogs were falsely categorized as protected, especially for CDV.

Proteomic analysis of canine vaccines

OBJECTIVE

To use proteomic analysis to identify qualitatively and quantitatively mammalian protein components of commercial veterinary vaccines against canine distemper, leptospirosis, borreliosis, and rabies.

SAMPLE

25 licensed veterinary vaccines (from 4 different manufacturers) against canine distemper and leptospirosis, borreliosis, and rabies (3-year and 1-year durations of immunity).

PROCEDURES

Duplicate samples from a single-lot vial of each vaccine were prepared by acetone precipitation and proteolysis with trypsin and Lys-C protease mix. Peptides mixtures (1 μg) were analyzed by liquid chromatography-tandem mass spectrometry using an Orbitrap Fusion Lumos mass spectrometer. Liquid chromatography-tandem mass spectroscopy data were searched against a Bos taurus protein database using MaxQuant to identify and quantify mammalian proteins in the vaccines. Identified proteins were classified by function and network analysis to visualize interactions.

RESULTS

The largest number of mammalian proteins was identified in 3-year rabies vaccines (median, 243 proteins; range, 184 to 339 proteins) and 1-year rabies vaccines (median, 193 proteins; range, 169 to 350 proteins). Borrelia and leptospirosis-distemper (L&D) vaccines had the lowest number of proteins. Rabies vaccines had the highest number of identified proteins in common (n = 316); 33 were unique to 1-year products and 44 were found in 3-year products. Borrelia and L&D vaccines had 16 and 22 uniquely identified proteins, respectively. The protein classifications were primarily modulators of protein-binding activity, enzymes, transfer-carrier proteins, cytoskeletal proteins, defense-immunity proteins, calcium-binding proteins, and extracellular matrix proteins.

CLINICAL RELEVANCE

This study demonstrates proteomics application to evaluate quality differences among different vaccines, identifying potential stimulants of desirable and undesirable immune responses.

Vasectomy and ovary-sparing spay in dogs: comparison of health and behavior outcomes with gonadectomized and sexually intact dogs

OBJECTIVE

To compare health and behavior outcomes for dogs that underwent vasectomy or ovary-sparing spay (hysterectomy) with sexually intact dogs or dogs that had undergone traditional castration or spay.

SAMPLE

6,018 dog owners responded to a web-based survey between November 3, 2021, and January 7, 2022.

PROCEDURES

Participants were asked demographic questions and to provide information about 1 or more dogs (living or deceased). Options for reproductive status were as follows: sexually intact, castrated, spayed (ovariohysterectomy or ovariectomy), vasectomy, or ovary-sparing spay (hysterectomy). Participants were asked questions about orthopedic and other health problems, cancer, and problematic behavior. Logistic regression models, survival analyses, and descriptive statistics were used to assess relationships between reproductive status and outcomes.

RESULTS

Owners provided valid surveys for 6,018 dogs, including 1,056 sexually intact, 1,672 castrated, and 58 vasectomized male dogs and 792 sexually intact, 2,281 spayed, and 159 female dogs that had undergone ovary-sparing spay. Longer exposure to gonadal hormones, regardless of reproductive status, was associated with reduced odds of general health problems and both problematic and nuisance behaviors.

CLINICAL RELEVANCE

To our knowledge, this study provides the first data on health and behavior outcomes of vasectomy and ovary-sparing spay in dogs and is the first to compare these outcomes to sexually intact and gonadectomized dogs. It adds to accumulating data on the mixed benefits and risks of removing the gonads to prevent reproduction and emphasizes the importance of developing an informed, case-by-case assessment of each patient, taking into consideration the potential risks and benefits of spaying or neutering and alternative reproductive surgeries.

Potential Drivers for the Re-Emergence of Canine Leptospirosis in the United States and Canada

Canine leptospirosis is an important zoonotic disease in many countries. This review examines potential drivers for increased diagnoses of canine leptospirosis in the United States and Canada, using the epidemiologic triad of agent-environment-host as a template. Leptospira spp. are classified into more than 250 serovars, but in many laboratories only 6 are routinely tested for in serologic agglutination tests of canine sera. Leptospiral infections in dogs may potentially go undetected with unemployed or currently employed diagnostic methods. Disease transmission from infected reservoir hosts usually occurs via urine-contaminated environmental sources such as water. Direct contact between infected and susceptible individuals, environmental factors such as climate changes in temperature and/or rainfall, and increasing number and urbanization of reservoir hosts may greatly increase dog exposure risks. A dog's lifestyle may influence exposure risk to leptospirosis, but vaccination based on proper identification of circulating serogroups dramatically reduces post-exposure infections. Regrettably, resistance to vaccination by veterinarians and dog owners leaves a large number of dogs at risk for this zoonotic disease.

2022 AAHA Canine Vaccination Guidelines

These guidelines are an update and extension of previous AAHA peer-reviewed canine vaccination guidelines published in 2017. Vaccination is a cornerstone of canine preventive healthcare and one of the most cost-effective ways of maintaining a dog's health, longevity, and quality of life. Canine vaccination also serves a public health function by forming a barrier against several zoonotic diseases affecting dogs and humans. Canine vaccines are broadly categorized as containing core and noncore immunizing antigens, with administration recommendations based on assessment of individual patient risk factors. The guidelines include a comprehensive table listing canine core and noncore vaccines and a recommended vaccination and revaccination schedule for each vaccine. The guidelines explain the relevance of different vaccine formulations, including those containing modified-live virus, inactivated, and recombinant immunizing agents. Factors that potentially affect vaccine efficacy are addressed, including the patient's prevaccination immune status and vaccine duration of immunity. Because animal shelters are one of the most challenging environments for prevention and control of infectious diseases, the guidelines also provide recommendations for vaccination of dogs presented at or housed in animal shelters, including the appropriate response to an infectious disease outbreak in the shelter setting. The guidelines explain how practitioners can interpret a patient's serological status, including maternally derived antibody titers, as indicators of immune status and suitability for vaccination. Other topics covered include factors associated with postvaccination adverse events, vaccine storage and handling to preserve product efficacy, interpreting product labeling to ensure proper vaccine use, and using client education and healthcare team training to raise awareness of the importance of vaccinations.

Leptospirosis vaccination in dogs attending UK primary care practices: vaccine uptake and factors associated with administration

Background

Leptospirosis is a zoonotic disease that is found globally and affects most mammalian species. Vaccination of dogs against leptospirosis is an important approach to preventing clinical disease, or reducing disease severity, as well as reducing transmission of the infection to humans. Although it is generally considered to be a ‘core’ vaccine, there is limited information on the level of leptospirosis vaccine usage and factors associated with its usage in dogs in the UK. The study aimed to report the uptake of leptospirosis vaccination and factors associated with its usage in a cohort of dogs under primary veterinary care during a 12-month period.

Results

From a population of 905,543 dogs, 49% (95%CI 48.9–49.1%) had at least one leptospirosis vaccine administered during the 12 months of study. Adult dogs had reduced odds of receiving a leptospirosis vaccine when compared to dogs < 1 year old, with dogs > 8 years old having a greater than ten-fold reduction in odds (OR = 0.08, 95%CI 0.07–0.09). Odds of receiving a leptospirosis vaccine was increased in insured dogs when compared to uninsured dogs (OR = 1.22, 95%CI = 1.17–1.28). Neutered dogs had reduced odds of receiving a leptospirosis vaccine (OR = 0.87, 95%CI 0.83–0.91). Breed associations with receiving a leptospirosis vaccine varied. Several breeds were associated with increased odds of receiving a leptospirosis vaccine when compared to crossbreed dogs, including Border Terriers (OR = 1.49, 95%CI 1.42–1.57), Golden Retrievers (OR = 1.30, 95%CI = 1.24–1.37), Cocker Spaniels (OR = 1.27, 95%CI 1.23–1.31) and West Highland White Terriers (OR = 1.27, 95%CI 1.22–1.31). French Bulldogs (OR = 0.64, 95%CI = 0.62–0.67), Staffordshire Bull Terriers (OR = 0.79, 95%CI 0.78–0.82) and Pugs (OR = 0.91, 95%CI =0.88–0.95) had significantly reduced odds of receiving a leptospirosis vaccination during the study.

Conclusion

This work identified that almost half of the UK primary care attending population received a leptospirosis vaccine during the year. Several demographic variables were associated with leptospirosis vaccine administration, with age being particularly important. Both the proportion of uptake and factors associated with leptospirosis vaccine usage can be used as a benchmark for comparisons in the future. Additionally, an understanding of which populations have reduced odds of receiving a leptospirosis vaccine can potentially be used for initiatives to encourage owner vaccination uptake in these groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03382-6.

Use of preventive measures and serological screening tools for Leishmania infantum infection in dogs from Europe

Background

There are several screening tools for detecting Leishmania infantum infection in dogs and various preventive measures to protect against it. Some studies have investigated them, but not many have described their current use. The aim of this study was to investigate which preventive measures and serological screening tools for L. infantum infection were employed from 2012 to 2018 in dogs from different endemic European countries.

Methods

A set of electronic datasheets was completed for each dog from several veterinary centres. Classification of preventive measures included: (1) repellents, (2) vaccines and (3) immunomodulators. Classification of serological tests included the: (1) direct agglutination test (DAT), (2) enzyme-linked immunosorbent assay (ELISA), (3) indirect immunofluorescence (IFI), (4) rapid tests and (5) other assays. Dogs were also classified depending on their risk of exposure and living area.

Results

Information from 3762 dogs was gathered. Preventive measures were applied in 91.5% of dogs and the most frequently used were repellents (86.2%) followed by vaccines (39.8%) and Leisguard^® (15.3%). The different types of repellents (collar and spot-on) were used similarly. A combination of a vaccine and repellents was preferred in the high-risk group while the low-risk preferred a combination of Leisguard^® and a repellent (Chi-square test: X² = 88.41, df = 10, P < 0.001). Furthermore, all preventive measures were similarly used through the years except for repellents, which were predicted to have a small increase of use each year. Regarding serological screening tools, the most used were rapid and ELISA tests. Rapid tests, ELISA tests and DAT were used similarly through the years, but a significant change was found in the use of IFI and other assays whose use decreased a little each year.

Conclusions

Repellents were the preferred measure, while vaccines and Leisguard^® were second-line options. Some dogs were not treated by any measures, which highlights the need for dog owner education. Moreover, there seems to be a preference for rapid tests in the clinical setting to detect specific L. infantum antibodies while ELISA or IFI are less often employed. This underlines an increasing problem, as qualitative rapid tests have a variable diagnostic performance limiting the adequate diagnosis of seropositive dogs in endemic areas.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05251-5.

Agreement between In-Clinics and Virus Neutralization Tests in Detecting Antibodies against Canine Distemper Virus (CDV)

Core vaccinations and specific antibody titer evaluations are strongly recommended worldwide by all the vaccination guidelines. Virus neutralization (VN) is considered the gold standard for measuring antibody titer against canine distemper virus, but it is complex and time consuming, and the use of in-clinics tests would allow to obtain quicker results. The aim of this study was to evaluate the agreement of the commercial in-clinics VacciCheck test compared to VN. A total of 106 canine sera were analyzed using both methods. The best agreement was obtained using a protective threshold of ≥1:32. VacciCheck showed 95.5% sensitivity, 87.2% specificity, and 92.5% accuracy. The Cohen’s kappa coefficient between methods was 0.84 (CI 95% 0.73 to 0.95), revealing an optimal agreement between the two methods (p = 0.0073). The evaluation of discordant results reveal that most samples had less than 1.5 dilution difference, and that usually did not affect the classification as protected or non-protected. Results also suggest that, in dubious cases, especially when a protective result is expected, retesting is advisable. In conclusion, VacciCheck may be considered as a reliable instrument that may help the clinician in identifying the best vaccine protocol, avoiding unnecessary vaccination, and thus reducing the incidence of adverse effects.

Variability in non-core vaccination rates of dogs and cats in veterinary clinics across the United States

Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician's assessment of a pet's risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0-96% for canine influenza, and 0-94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.

Clinical characteristics of two-hundred thirty-two dogs (2006-2018) treated for suspected anaphylaxis in Perth, Western Australia

OBJECTIVE

To describe the clinical features of dogs treated for suspected anaphylaxis in Perth, Western Australia.

DESIGN

Single-centre observational case series with retrospective and prospective phases.

METHODS

This was a two-phase study of dogs with clinical suspicion of anaphylaxis presenting to the emergency service of a university teaching hospital. Dogs required evidence of, and appropriate treatment of, a type 1 hypersensitivity reaction as well as two or more organs affected (or cardiovascular signs alone) to be included. Phase 1 includes retrospective case series of 186 dogs (March 2006-December 2018). Phase 2 includes prospective descriptive case series of 46 dogs (October 2017-July 2018) focused on clinical signs.

RESULTS

In phase 1, 88 (47%) dogs had evidence of insect exposure prior to the acute event. One hundred forty (75%) dogs had dermatological signs, 141 (76%) had gastrointestinal signs and 129 (69%) had cardiovascular signs. Ninety-two (49%) dogs had vasoconstrictive shock (5 with bradycardia), 24 (13%) had vasodilatory shock, 8 (4%) had mixed vasodilatory and vasoconstrictive shock and 5 (3%) had unclassifiable shock. On focused abdominal ultrasound, 42 of 71 (59%) dogs had gallbladder wall oedema and 3 of 71 (4%) dogs had peritoneal free fluid. In phase 2, the distributions of insect exposure, organ dysfunction and sonographic abnormalities were similar to phase 1.

CONCLUSION

Dogs presenting with suspected anaphylaxis showed a broad range of presentations. Dermatological signs were absent in a proportion of dogs, vasoconstrictive shock was more frequent than vasodilatory and unique features of shock were identified. This study highlights the challenges of diagnosis based on presenting features alone.

[Prevention of canine parvovirosis - Part 3: Vaccine-associated adverse events]

Although nowadays vaccines, especially those against canine parvovirus (CPV), are considered to be safe, vaccine-associated adverse events (VAAEs) can occur in rare cases. Some VAAEs are mild and manifest shortly (within a few days) after vaccination (e. g. gastrointestinal signs, fever, reduced general condition, lymphadenopathy). These signs are likely a result of vaccine virus replication and indicate a good immune response. Anaphylactic reactions can also occur promptly following vaccine administration and might be life threatening. Affected dogs show clinical signs such as edema, salivation, vomiting, diarrhea, hypotension, and/or shock. Since it is often unclear which component of the vaccine carries responsibility for the anaphylactic reaction it is important to limit future vaccinations of these dogs to indispensable components only. When revaccination is unavoidable, e. g. because antibodies against CPV cannot be detected, combined vaccines should not be used and CPV (and other components, if needed) should preferably be vaccinated separately. Changing the vaccine manufacturer might also prevent further anaphylactic reactions. Finally, there are VAAEs occurring after a prolonged period of time. In dogs, it is discussed that autoimmune diseases, such as immune-mediated hemolytic anemia (IMHA), can be a consequence of excessive vaccination or in the least be triggered by vaccination. Numerous dogs with IMHA are reported to have a history of receiving a vaccination within a few weeks before the onset of clinical sings. In such dogs, further vaccinations should generally be avoided.

Preventive Health Care for Working Dogs

The goal of preventive care is to maintain and optimize health by averting preventable problems. Effective preventive care programs for working dogs must incorporate standard procedures applicable to dogs in general with additional elements pertinent to the more specific characteristics of breed, geographic location, living and working conditions, and physical and mental tasks required of the working dog. This article covers the basic essential preventive health guidelines for all working dogs as well as the specific breed, occupational, and regional considerations to be taken into account.

Prevalence of Neutralizing Antibodies to Canine Distemper Virus and Response to Vaccination in Client-Owned Adult Healthy Dogs

Re-vaccinations against canine distemper virus (CDV) are commonly performed in 3-year intervals. The study's aims were to determine anti-CDV antibodies in healthy adult dogs within 28 days of vaccination against CDV, and to evaluate factors associated with the presence of pre-vaccination antibodies and with the antibody response to vaccination. Ninety-seven dogs, not vaccinated within 1 year before enrollment, were vaccinated with a modified live CDV vaccine. A measurement of the antibodies was performed before vaccination (day 0), on day 7, and 28 after the vaccination by virus neutralization. A response to vaccination was defined as a ≥4-fold titer increase by day 28. Fisher's exact test was used to determine factors associated with a lack of antibodies and vaccination response. In total, 94.8% of the dogs (92/97; CI 95%: 88.2-98.1) had antibodies (≥10) prior to vaccination. A response to vaccination was not observed in any dog. Five dogs were considered humoral non-responders; these dogs neither had detectable antibodies before, nor developed antibodies after vaccination. Young age (<2 years) was significantly associated with a lack of pre-vaccination antibodies (p = 0.018; OR: 26.825; 95% CI: 1.216-1763.417). In conclusion, necessity of re-vaccination in adult healthy dogs should be debated and regular vaccinations should be replaced by antibody detection.

Most Dogs Are Not NATIVE Dogs

Studies of dogs have proliferated among canine scientists, aided in part by the logistical convenience of working with owned animals whose care is handled by others. These pet dogs are unlike most dogs that have lived in contemporary or prehistoric settings. In particular, many of the dogs studied by canine scientists are NATIVE dogs: (1) neutered, (2) alimented, (3) trained, (4) isolated, (5) vaccinated, and (6) engineered. The distinct genotypes and unusual environments of NATIVE dogs stand in contrast to the characteristics of dogs who have adapted to lives in other human communities and settings. For a holistic perspective on the evolution of dogs, it is helpful to study dogs in environments that share features of the settings in which dogs evolved.

Retrospective review of diphenhydramine versus diphenhydramine plus glucocorticoid for treatment of uncomplicated allergic reaction in dogs

OBJECTIVE

To report the outcome of treatment of uncomplicated allergic reactions in dogs with diphenhydramine vs diphenhydramine plus glucocorticoid and to determine the incidence rate of uncomplicated allergic reactions DESIGN: Retrospective study between January 1, 2012 and August 15, 2018.

SETTING

Privately owned, 24-hour emergency and specialty referral veterinary hospital.

ANIMALS

Eight hundred and eighty cases of dogs treated for uncomplicated allergic reaction with diphenhydramine alone or in combination with a glucocorticoid.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred ninety-nine dogs were treated with diphenhydramine alone, and 581 were treated with diphenhydramine plus Dex SP. There was no difference between the 2 groups for response to initial therapy, need for additional veterinary intervention after discharge, or persistent signs at follow-up. The cumulative incidence of emergency department presentation for uncomplicated allergic reaction in this hospital was 1.2%.

CONCLUSIONS

There was no difference in measured outcomes between dogs treated with diphenhydramine alone vs those treated with a glucocorticoid in addition to diphenhydramine in this population of dogs.

Early Life Vaccination of Companion Animal Pets

Development of the immune system of mammalian animal species parallels that of humans and involves the innate and adaptive (acquired) immune responses acting together with the thymus gland. Consequently, issues surrounding the adequacy and safety of vaccinations to protect pet animals from their relevant infectious diseases need to be addressed just as they are for humans. Pet animals, especially canines, also have unique needs because of the wide diversity of purebred and mixed breeds that vary greatly in size, type, temperament, and even maturation rates. Furthermore, pets in early life encounter a series of changes that can affect their development and induce stressors including parasite control, new homes and environment, novel foods, and the socialization that is essential at a time when vaccinations need to be given. While recognizing that this overall need is becoming more understood, current vaccination policy guidelines for companion animals are still only adhered to by about 40% of veterinarians worldwide. Clearly, vaccination of pets should no longer be considered as "one size fits all".

Adverse consequences of vaccination

The importance of adverse effects from vaccination must not be overstated. Vaccine benefits greatly exceed any risks from the procedure. Neither must they be minimized. Unnecessary vaccination must be discouraged. Hypersensitivity reactions to vaccine components are real and must be guarded against. Residual virulence, although a concern tends to be more a hypothetical than a real problem. Progressive improvements in animal vaccines have significantly reduced the chances of adverse effects occurring, although some issues persist. One such example is injection-site sarcomas in cats. Another issue is the influence of animal size on the prevalence of adverse events in dogs.

Risk of Development of Chronic Kidney Disease After Exposure to Borrelia burgdorferi and Anaplasma spp

Lyme disease is a multi-faceted illness caused by infection due to Borrelia burgdorferi. Acute kidney damage secondary to Lyme disease is well described but less so as a chronic event. The role of Anaplasma spp. and secondary kidney dysfunction is not known. A retrospective cohort study was performed to determine if dogs within a defined Lyme disease and anaplasmosis region with B. burgdorferi or Anaplasma spp. antibodies had an increased risk of chronic kidney disease (CKD). Patient exposure was defined as having a B. burgdorferi or Anaplasma spp. antibody positive result recorded at any point in the available patient history. CKD was defined as concurrent increased symmetric dimethylarginine and creatinine (Cr) for a minimum of 25 days with inappropriate urine specific gravity (USG). Patients were matched using propensity scoring to control for age, region, and breed. Contingency tables were used to compare dogs seropositive and not seropositive to B. burgdorferi and Anaplasma spp. and CKD outcome. For each comparison that was performed, statistical significance was defined by a P-value of <.025. The risk ratio of CKD for patients exposed to B. burgdorferi and Anaplasma spp. were found to be 1.43 (95% confidence interval [CI, 1.27, 1.61], P < .0001) and 1.04, (95% CI [0.87, 1.24], P = .6485), respectively. Results suggest in this cohort no increased risk for developing CKD when exposed to Anaplasma spp. but a significant increase in risk for developing CKD with exposure to B. burgdorferi.

Recommendations on vaccination for Latin American small animal practitioners: a report of the WSAVA Vaccination Guidelines Group

The World Small Animal Veterinary Association Vaccination Guidelines Group has produced global guidelines for small companion animal practitioners on best practice in canine and feline vaccination. Recognising that there are unique aspects of veterinary practice in certain geographical regions of the world, the Vaccination Guidelines Group undertook a regional project in Latin America between 2016 and 2019, culminating in the present document. The Vaccination Guidelines Group gathered scientific and demographic data during visits to Argentina, Brazil and Mexico, by discussion with national key opinion leaders, visiting veterinary practices and review of the scientific literature. A questionnaire survey was completed by 1390 veterinarians in five Latin American countries and the Vaccination Guidelines Group delivered continuing education at seven events attended by over 3500 veterinarians.

The Vaccination Guidelines Group recognised numerous challenges in Latin America, for example: (1) lack of national oversight of the veterinary profession, (2) extraordinary growth in private veterinary schools of undetermined quality, (3) socioeconomic constraints on client engagement with preventive health care, (4) high regional prevalence of some key infectious diseases (e.g. feline leukaemia virus infection, canine visceral leishmaniosis), (5) almost complete lack of minimal antigen vaccine products as available in other markets, (6) relative lack of vaccine products with extended duration of immunity as available in other markets, (7) availability of vaccine products withdrawn from other markets (e.g. Giardia vaccine) or unique to Latin America (e.g. some Leishmania vaccines), (8) accessibility of vaccines directly by pet owners or breeders such that vaccination is not delivered under veterinary supervision, (9) limited availability of continuing education in veterinary vaccinology and lack of compulsion for continuing professional development and (10) limited peer‐reviewed published scientific data on small companion animal infectious diseases (with the exception of leishmaniosis) and lack of support for such academic research.

In this document, the Vaccination Guidelines Group summarises the findings of this project and assesses in evidence‐based fashion the scientific literature pertaining to companion animal vaccine‐preventable diseases in Latin America. The Vaccination Guidelines Group makes some recommendations on undergraduate and postgraduate education and academic research. Recognising that current product availability in Latin America does not permit veterinarians in these countries to vaccinate according to the global World Small Animal Veterinary Association guidelines, the Vaccination Guidelines Group makes a series of “pragmatic” recommendations as to what might be currently achievable, and a series of “aspirational” recommendations as to what might be desirable for the future. The concept of “vaccine husbandry” is addressed via some simple guidelines for the management of vaccine products in the practice. Finally, the Vaccination Guidelines Group emphasises the global trend towards delivery of vaccination as one part of an “annual health check” or “health care plan” that reviews holistically the preventive health care needs of the individual pet animal. Latin American practitioners should transition towards these important new practices that are now well embedded in more developed veterinary markets.

The document also includes 70 frequently asked questions and their answers; these were posed to the Vaccination Guidelines Group during our continuing education events and small group discussions and should address many of the issues surrounding delivery of vaccination in the Latin American countries. Spanish and Portuguese translations of this document will be made freely available from the on‐line resource pages of the Vaccination Guidelines Group.

Neutering in dogs and cats: current scientific evidence and importance of adequate nutritional management

Neutering or spaying is a commonly recommended veterinary procedure. However, veterinarians are often confronted with conflicting findings and differences in concepts regarding practice and proper nutritional management after the procedure. The objective of the present review was to bring to light the most recent literature, summarise it and discuss the findings focusing on the risks and benefits of neutering in dogs and cats, and to determine the appropriate nutritional management for these animals.

Imaging and pathological findings of intramedullary inflammatory pseudotumour in a miniature dachshund: a case report

Background

Inflammatory pseudotumours (IPTs) are distinctive lesions consisting of myofibroblastic spindle cells and a variety of inflammatory cells. The aetiology of IPTs is unknown. Reports of IPTs in veterinary medicine have been scarse. Moreover, only one case of intradural extramedullary IPT has been previously reported. In this report, we introduce the first known case of canine IPT, which occurred in the parenchyma of the spinal cord.

Case presentation

A 10-year-old female Miniature Dachshund presented with a 2-month-long history of progressively worsening ataxia and tetraparesis. Neurological examination was consistent with a lesion involving the cervical spinal cord. Magnetic resonance imaging revealed an intradural space-occupying lesion in the region of the fourth cervical vertebra. Dorsal laminectomy and resection of the mass were performed. Histopathological examination revealed the proliferation of immature spindle cells (fibroblasts/myofibroblasts and glial cells) and a highly cellular mixture of neutrophils, macrophages and lymphocytic cells. The mass was located in the parenchyma of the spinal cord and was diagnosed as an IPT occurring in the parenchyma of the spinal cord. No causative pathogen was detected. The dog’s symptoms improved, during the first month after surgery. However, neurological symptoms, such as laboured breathing and dysuria, subsequently worsened and the dog died 42 days after surgery.

Conclusions

The present study describes a canine case of IPT occurring in the parenchyma of the spinal cord. The diagnosis and determination of the site of the mass was difficult solely based on preoperative imaging in the present case. The outcome of this case was poorer than that observed in cases of canine extramedullary IPT and human intramedullary IPT, in which the patients exhibited recovery. The prognosis after surgical resection cannot be decided from the present case alone. However, patients should be monitored for potential serious complications and recurrence.

Detection of aluminum in lumbar spinal cord of sheep subcutaneously inoculated with aluminum-hydroxide containing products

The use of vaccines containing aluminum (Al) adjuvants is widespread in ovine production. Al adjuvants induce an effective immune-response but lead to the formation of post-vaccination granulomas from which Al can disseminate. This work aims to study the accumulation of Al in the central nervous system of sheep subcutaneously inoculated with Al-hydroxide containing products. Lumbar spinal cord and parietal lobe from 21 animals inoculated with 19 doses of Vaccine (n = 7), Adjuvant-only (n = 7) or phosphate-buffered saline as Control (n = 7) were analyzed with transversely heated graphite furnace atomic absorption spectroscopy and lumogallion staining for Al analytical measurements and Al tisular localization respectively. In the lumbar spinal cord, Al median content was higher in both the Adjuvant-only and Vaccine group (p = .001) compared with the Control group. Animals of the Adjuvant-only group showed the higher individual measurements in the lumbar spinal cord (14.36 μg/g and 7.83 μg/g). In the parietal lobe, Al median content tended to be higher in the Adjuvant-only group compared with Control group (p = .074). Except for three replicates of the Adjuvant-only group, Al content was always below 1 μg/g. In the lumbar spinal cord, lumogallion-reactive Al deposits were more abundant in the gray matter than in the white matter in both Vaccine (p = .034) and Adjuvant-only groups (p = .017) and Al deposits were mostly associated with glial-like cells (p = .042). In the parietal lobe, few Al deposits, which were sometimes related to blood vessels, were found. In sheep, Al-hydroxide adjuvants inoculated in the subcutaneous tissue selectively accumulate in the lumbar spinal cord.

Knowledge, attitudes, and practices among veterinarians during an outbreak of canine leptospirosis-Maricopa County, Arizona, 2017

Leptospirosis, caused by Leptospira spp., is a zoonotic bacterial disease important to both human and animal health. Six pathogenic serovars are currently known to commonly infect and cause disease in dogs in the United States. While canine leptospirosis infection is historically rare in Arizona (≤5 cases reported annually) (ADHS unpublished data) several clusters were reported in Maricopa County (MC) during February 2016-January 2017. Public health initiated an outbreak response and developed a knowledge, attitudes, and practices survey for veterinarians. The goals were to determine awareness and general attitudes about canine leptospirosis and to identify gaps in veterinarians' knowledge in treatment and prevention. We distributed a 40-question self-administered online survey to 1058 Arizona Veterinary Medical Association members, made available during February 9-May 15, 2017. We analyzed the results using Pearson's Chi-squared or Fisher's exact test; a P-value <0.05 was considered statistically significant. We analyzed 202 complete responses. Veterinarians from 10 (66%) of 15 Arizona counties were represented. MC practices were more likely to stock leptospirosis vaccine (80%) than other counties combined (58%) (P = 0.004). The average composite knowledge score was 24.4 out of 38 (range 12-37, median 24); 49% of respondents demonstrated higher knowledge as defined by authors, largely in identification of leptospirosis risk factors (86%) and routes of exposure (73%). Fewer than half (45%) of respondents correctly identified the length of time bacteria can be shed in dogs' urine. Eighty-one percent of respondents demonstrated lower knowledge about clinical signs associated with leptospirosis; only 47% of respondents identified eight clinical signs commonly associated with leptospirosis. Sixty-one percent of MC respondents agreed that leptospirosis is an important canine disease in their geographic area, while only 40% of other county respondents agreed (P=0.03). Seventy percent of respondents identified diagnostic testing options. The majority correctly selected infection-control practices in line with recommendations from 2 national clinical guidelines. More respondents would recommend leptospirosis vaccination if dogs traveled or lived in rural areas (87-96%) than if dogs attended day care or were boarded (63%). We identified opportunities for education, including the local epidemiology of leptospirosis, transmission prevention strategies, vaccine safety, testing, clinical identification, and emerging risk factors. Our findings will help guide the design of educational materials for small animal veterinarians in Arizona regarding recommendations for prevention of animal and human leptospirosis infections; these efforts could also shift the culture of reporting companion animal diseases to improve future One Health collaborations.

From the bluetongue vaccination campaigns in sheep to overimmunization and ovine ASIA syndrome

The use of vaccines has proven to be very effective in controlling and eradicating infectious diseases, both in veterinary and human medicine; however, vaccines can be also the source of an array of problems caused by procedures such as overimmunization. Bluetongue, an orbiviral disease that affects ruminants, is best controlled by the use of inactivated vaccines. During the last years of the past decade, these vaccines were applied all over Europe to control the spreading of the disease, a goal that was accomplished; however, at the same time, several adverse effects related to the vaccination were reported. Especially in sheep, this vaccination campaign brought out a new cachectic and neurologic disease with harmful consequences for the ovine industry. This disease is now recognized as the ovine version of the autoimmune/inflammatory syndrome induced by adjuvants (ASIA syndrome) and poses an immense challenge in veterinary medicine, immunology, and vaccinology.

Effects of sex and birth weight on non-specific health services use following whole-cell pertussis vaccination: a self-controlled case series analysis

Previous studies from low-resource countries have highlighted concerns surrounding non-specific effects of whole-cell pertussis vaccination, particularly in females. We sought to examine the effects of sex and birth weight on health services utilization following first exposure to whole-cell pertussis vaccine. Using a self-controlled case series design and by calculating relative incidence ratios (RIRs), we compared the relative incidence of emergency department visits and/or hospital admissions between sexes and between birth weight quintiles. Females had a higher relative incidence of events following vaccination compared to males (RIR = 1.13, 95% CI: 0.99, 1.30), which persisted after adjustment for birth weight (RIR = 1.12, 95% CI: 0.97, 1.28). We also observed a trend of increasing relative incidence of events over decreasing quintiles of birth weight; infants in the lowest quintile had a 26% higher relative event rate compared to the highest quintile, which was robust to adjustment for sex (Unadjusted RIR = 1.26, 95% CI: 1.01, 1.56; Adjusted RIR = 1.23, 95% CI: 0.99, 1.53). The risk of all-cause health services utilization immediately following vaccination, was elevated in female infants and infants having lower birth weight. Further study is warranted to determine if vaccine dosing should take infant weight into account.

Rabies: Current Preventive Strategies

Desensitization to rabies is a result of successfully eliminating canine rabies in the United States, which occurred in 2007; however, the need for mandatory rabies vaccination in pets remains. Rabies cases are rare in comparison with other vaccine-preventable diseases in companion animals; however, because it is a zoonotic disease with the highest case fatality rate of any infectious disease demands the establishment of strict laws for disease prevention. Preventive strategies include addressing current concerns in consideration of disease surveillance, appropriate vaccination recommendations, and local regulations protecting public health.

Validation of text-mining and content analysis techniques using data collected from veterinary practice management software systems in the UK

Electronic patient records from practice management software systems have been used extensively in medicine for the investigation of clinical problems leading to the creation of decision support frameworks. To date, technologies that have been utilised for this purpose such as text mining and content analysis have not been employed significantly in veterinary medicine. The aim of this research was to pilot the use of content analysis and text-mining software for the synthesis and analysis of information extracted from veterinary electronic patient records. The purpose of the work was to be able to validate this approach for future employment across a number of practices for the purposes of practice based research. The approach utilised content analysis (Prosuite) and text mining (WordStat) software to aggregate the extracted text. Text mining tools such as Keyword in Context (KWIC) and Keyword Retrieval (KR) were employed to identify specific occurrences of data across the records. Two different datasets were interrogated, a bespoke test dataset that had been set up specifically for the purpose of the research, and a functioning veterinary clinic dataset that had been extracted from one veterinary practice. Across both datasets, the KWIC analysis was found to have a high level of accuracy with the search resulting in a sensitivity of between 85.3-100%, a specificity of between 99.1-99.7%, a positive predictive value between 93.5-95.8% and a negative predictive value between 97.7-100%. The KR search, based on machine learning, was utilised for the clinic-based dataset and was found to perform slightly better than the KWIC analysis. This study is the first to demonstrate the application of content analysis and text mining software for validation purposes across a number of different datasets for the purpose of search and recall of specific information across electronic patient records. This has not been demonstrated previously for small animal veterinary epidemiological research for the purposes of large scale analysis for practice-based research. Extension of this work to investigate more complex diseases across larger populations is required to fully explore the use of this approach in veterinary practice.

The serological response in dogs inoculated with canine distemper virus vaccine at the acupuncture point governing vessel-14: A randomized controlled trial

The improvement of immunity to vaccination has historically focused on manipulation of antigen presentation rather than the host. Immune modulation by stimulating specific acupuncture points along the Meridian System has been practiced in Traditional Chinese Medicine. The purpose of this study was to quantitatively determine whether acupoint vaccination, in which vaccine is administered at an acupuncture point in dogs, has the potential to enhance the immune response. A randomized controlled trial was conducted to compare the effectiveness of acupoint vaccination versus a conventional method, based on humoral immune response in dogs given Canine Distemper Vaccine (CDV). One hundred client-owned dogs were admitted to the study with following characteristics: (1) passed a routine physical exam, (2) aged between 1 and 10 years old, (3) had no history of chronic disease, and (4) were not on immunomodulating medications. Dogs were randomly assigned to either the Acupuncture group inoculated at the acupoint Governing Vessel (GV)-14, or to the Control group inoculated conventionally at a non-acupuncture site. Mean changes from Day0 to Day14 of the response to CDV vaccination, measured by serum neutralization (SN) titers with log-transformation for reducing outlier effects, were compared between groups. No significant difference was found between groups in age, weight, or sex (all p >0.2). Both groups had significant increases of CDV SN titer post-vaccination (p < 0.001). The mean increase in Acupuncture group (0.72; SD = 0.79) was significantly greater than that of the Control group (0.36; SD = 0.67); p = 0.019. Inference on percentage of change in raw SN titer data further revealed that the effects in the Acupuncture group was significantly greater than the Control group (242% vs. 83%; p = 0.02). This study demonstrated that Acupoint vaccination at GV-14 resulted in a significantly elevated humoral immune response to CDV vaccine compared to Controls, which suggests the potential of acupoint vaccination to enhance the immune response.

Vaccination and Associated Adverse Events in Dogs Previously Treated for Primary Immune-Mediated Hemolytic Anemia

This study described the rate of vaccine reactions in a population of dogs receiving vaccines after diagnosis of primary immune-mediated hemolytic anemia (IMHA). A secondary objective was to describe the time elapsed between vaccination and initial diagnosis of IMHA. A medical record search identified cases meeting criteria for primary IMHA. Owners and referring veterinarians were surveyed regarding vaccination of the dog following diagnosis. Referring veterinarians were surveyed regarding vaccination prior to diagnosis of IMHA. A completed survey was returned in 44 cases. Twenty-two dogs received vaccinations after diagnosis, and 22 dogs did not. The median time elapsed between vaccination and initial diagnosis was 280 days. No dog was vaccinated within 30 days of diagnosis. Two of the following possible reactions were noted out of 22 dogs vaccinated: vomiting and urticarial eruption in a dog administered a rabies and canine distemper vaccine, and recurrent anemia in a dog administered a rabies vaccine. The rate of vaccine reactions was higher than previously reported, although the time period evaluated was longer than in previous studies. The relationship between initial vaccination and development of IMHA, and between vaccination and vaccine reaction, in this population is uncertain and may reflect coincidence or differences in susceptibility.

Safety Analysis of Leishmania Vaccine Used in a Randomized Canine Vaccine/Immunotherapy Trial

In Leishmania infantum-endemic countries, controlling infection within dogs, the domestic reservoir, is critical to public health. There is a need for safe vaccines that prevent canine progression with disease and transmission to others. Protective vaccination against Leishmania requires mounting a strong, inflammatory, Type 1 response. Three commercially available canine vaccines on the global veterinary market use saponin or inflammatory antigen components (Letifend) as a strong pro-inflammatory adjuvant. There is very little information detailing safety of saponin as an adjuvant in field trials. Safety analyses for the use of vaccine as an immunotherapeutic in asymptomatically infected animals are completely lacking. Leishmania infantum, the causative agent of canine leishmaniasis, is enzootic within U.S. hunting hounds. We assessed the safety of LeishTec^® after use in dogs from two different clinical states: 1) without clinical signs and tested negative on polymerase chain reaction and serology or 2) without clinical signs and positive for at least one Leishmania diagnostic test. Vaccine safety was assessed after all three vaccinations to quantify the number and severity of adverse events. Vaccinated animals had an adverse event rate of 3.09%, whereas placebo animals had 0.68%. Receiving vaccine was correlated with the occurrence of mild, site-specific, reactions. Occurrence of severe adverse events was not associated with having received vaccine. Infected, asymptomatic animals did not have a higher rate of adverse events. Use of vaccination is, therefore, likely to be safe in infected, asymptomatic animals.

Another Look at the "Dismal Science" and Jenner's Experiment

The follow-up to Jenner's experiment, routine vaccination, has reduced more disease and saved more vertebrate lives than any other iatrogenic procedure by orders of magnitude. The unassailability of that potentially provocative cliché has been ciphered in human medicine, even if it is more difficult in our profession. Most public relations headaches concerning vaccines are a failure to communicate, often resulting in overly great expectations. Even in the throes of a tight appointment schedule remembering and synopsizing (for clients), some details of the dismal science can make practice great again.

Evaluation of the efficacy of the Japanese rabies RC-HL strain vaccine in domestic dogs using past and present data: Prediction based on logistic regression and meta-analysis

Japan is one of the few rabies-free countries or territories (under the OIE standard) which still implement the policy of mandatory vaccination of domestic dogs. Under the Rabies Prevention Law enacted since 1950, pet owners in Japan are obliged to vaccinate their dogs every year. However, the national vaccination rate is estimated to average 42% over the past decade. Given this low owner compliance, there is debate over whether or not the mandatory vaccination policy should be maintained and if it were to be maintained, whether the yearly booster requirement is necessary or not. Data on 144 companion dogs vaccinated with the Japanese rabies RC-HL strain vaccine were analysed using multiple logistic regression. An extensive literature review was conducted and five previous vaccination studies were selected for meta-analysis. Results of logistic regression indicate that the proportion of dogs having a satisfactory antibody level lasting for 12 months (P_protected₁₂) with only one vaccination was 74.7% (95% prediction interval (PI): 51.4%-90.5%). By contrast, P_protected₁₂ for dogs vaccinated 2-4 times and 5 times or more was estimated as 96.6% (95%PI: 83.1%-99.3%) and 98.7% (95%PI: 96.9%-99.6%), respectively. Moreover, P_protected for 36 months would drop to 33.4% (95%PI: 11.4%-71.6%) for dogs vaccinated only once, while it would be 83.0% (95% PI: 39.4%-97.1%) and 93.0% (95%PI: 59.7%-99.2%) for dogs vaccinated 2-4 times and 5 times or more, respectively. The pooled P_protected for at least 12 months from meta-analysis was estimated as 83.8% (95%CI: 66.1%-97.5%) for dogs vaccinated only once, while it was estimated as 94.7% (95%CI: 87.7%-99.1%) for dogs vaccinated at least twice. Therefore, the yearly booster requirement of the current mandatory vaccination policy in Japan is reasonable in terms of its frequency. However, there is potential for future policy amendment to one that requires less frequent boosters, i.e. a booster is required within one year after primary vaccination and then every two to three years.

Clinical, serological and echocardiographic examination of healthy field dogs before and after vaccination with a commercial tetravalent leptospirosis vaccine

Background

Leptospirosis is a re-emerging bacterial zoonosis caused by spirochetes of the genus Leptospira. Severe disease has been reported in dogs in Europe despite vaccination with bivalent Leptospira vaccines. Recently, a tetravalent canine Leptospira vaccine (Nobivac® L4) was licenced in Europe. The goal of this study was to investigate clinical signs, microscopic agglutination test (MAT) titres, haematology, blood biochemistry, cardiac (c) Troponin I levels and echocardiography before and after vaccination with this tetravalent vaccine. Forty-eight healthy dogs were prospectively enrolled and vaccinated twice, 3–4 weeks apart (T0 and T1). Before vaccination (T0) and 16–31 days after the second vaccination (T2), MAT (n = 48), haematology (n = 48), blood biochemistry (n = 36) and cTroponin I measurements (n = 29) were performed, and MAT was repeated 347–413 days after the second vaccination (T3, n = 44). Echocardiography was performed before the first and second vaccination (T0 and T1, n = 24).

Results

Mild and transient clinical signs within 5 days following the first and second vaccination occurred in 23% and 10% of the dogs, respectively. Before the first vaccination (T0), all dogs showed negative MAT titres for the tested serovars except for Canicola (50% with titres 100–400). At T2, positive MAT titres to the serovars Canicola (100%), Australis (89%), Grippotyphosa (86%), Bratislava (60%), Autumnalis (58%), Copenhageni (42%), Pomona (12%), Pyrogenes (8%) and Icterohaemorrhagiae (2%) were found. Median to high titres (≥ 400) were most common to the serovar Canicola (92%) and less common to the serovars Australis (41%), Grippotyphosa (21%), Bratislava (12%), Autumnalis (4%), Pyrogenes (4%) and Pomona (2%). At T3, positive MAT titres (titre range: 100–400) were found in 2–18% of the dogs to serovars of the vaccine serogroups and in 2–18% of the dogs to the non-vaccine serovars Pomona, Autumnalis, Pyrogenes and Ballum. Haematology, blood biochemistry, cTroponin I levels and echocardiography results did not change significantly following vaccination.

Conclusions

Clinical signs following vaccination with Nobivac® L4 were transient and mild in all cases. Seroconversion differed considerably among individual dogs and among the vaccine serogroups.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-017-1056-x) contains supplementary material, which is available to authorized users.

Incidence rates and risk factors for owner-reported adverse events following vaccination of dogs that did or did not receive a Leptospira vaccine

OBJECTIVE

To determine incidence rates (IRs) and potential risk factors for owner-reported adverse events (AEs) following vaccination of dogs that did or did not receive a Leptospira vaccine.

DESIGN

Observational, retrospective cohort study.

ANIMALS

130,557 dogs.

PROCEDURES

Electronic records of mobile veterinary clinics from June 2012 to March 2013 were searched to identify dogs that received ≥ 1 vaccine in a given visit. Signalment data, vaccinations received, medications administered, and owner-reported clinical signs consistent with AEs that developed ≤ 5 days after vaccination were recorded. Associations between potential risk factors and owner-reported AEs were evaluated by logistic regression analysis.

RESULTS

The IR/10,000 dogs for owner-reported postvaccination AEs was 26.3 (95% CI, 23.6 to 29.2), whereas that for dogs that received a Leptospira vaccine alone or with other vaccines was 53.0 (95% CI, 42.8 to 64.9). Significant factors for increasing or decreasing risk of AEs were as follows: receiving a Leptospira vaccine (adjusted OR, 2.13), age at vaccination 1 to < 7 or ≥ 7 years (vs a referent of < 6 months; adjusted OR, 0.54 and 0.44, respectively), and weight 13.6 to < 22.7 kg (30 to < 50 lb) and 22.7 to < 45.5 kg (50 to 100 lb [vs a referent of < 4.5 kg {10 lb}]; adjusted OR, 0.48 and 0.55, respectively). Hypersensitivity reactions were rare (IR, 6.5/10,000 dogs), and IRs for these events did not differ significantly between dogs vaccinated with or without a Leptospira component.

CONCLUSIONS AND CLINICAL RELEVANCE

The overall IR for owner-reported postvaccination AEs was low. Results suggested vaccination against Leptospira (an organism that can cause fatal disease) is safe in the majority of cases, slightly increasing the risk of owner-reported AEs but not associated with a significant increase in hypersensitivity reactions, compared with other vaccinations administered.

Green synthesis and evaluation of silver nanoparticles as adjuvant in rabies veterinary vaccine

Background

Green synthesis of nanoparticles by plant extracts plays a significant role in different applications. Recently, several studies were conducted on the use of nanoparticles as adjuvant. The main aim of this study was to evaluate green synthesized silver nanoparticles (AgNPs) as adjuvant in rabies veterinary vaccine and compare the results with the existing commercially available alum adjuvant.

Materials and methods

In the current study, AgNPs were prepared by the reduction of aqueous silver nitrate by leaf extract of Eucalyptus procera. The formation of AgNPs was confirmed by ultraviolet (UV)–visible spectrophotometer, scanning electron microscopy, dynamic light scattering, and X-ray diffraction analysis. Then, different amounts of AgNPs (200 µg, 400 µg, 600 µg, and 800 µg) were added to 1 mL of inactivated rabies virus. The loaded vaccines (0.5 mL) were injected intraperitoneally into six Naval Medical Research Institute mice in each group on days 1 and 7. On the 15th day, the mice were intracerebrally challenged with 0.03 mL of challenge rabies virus (challenge virus strain-11, 20 lethal dose [20 LD₅₀]), and after the latency period of rabies disease in mice (5 days), the mice were monitored for 21 days. Neutralizing antibodies against rabies virus were also investigated using the rapid fluorescent focus inhibition test method. The National Institutes of Health test was performed to determine the potency of optimum concentration of AgNPs as adjuvant. In vitro toxicity of AgNPs was assessed in L929 cell line using MTT assay. In addition, in vivo toxicity of AgNPs and AgNPs-loaded vaccine was investigated according to the European Pharmacopeia 8.0.

Results

AgNPs were successfully synthesized, and the identity was confirmed by UV–visible spectrophotometry and X-ray diffraction analysis. The prepared AgNPs were spherical in shape, with an average size of 60 nm and a negative zeta potential of −14 mV as determined by dynamic light scattering technique. The highest percentage of viability was observed at 15 mg/kg and 20 mg/kg of AgNPs-loaded vaccine concentrations after injecting into the mice. The calculated potencies for alum-containing vaccine and AgNPs-loaded vaccine (dose 15 mg/kg) were 1.897 and 1.303, respectively. MTT assay demonstrated that alum at the concentration of 10 mg/mL was toxic, but AgNPs were not toxic. The in vivo toxicity also elucidated the safety of AgNPs and AgNPs-loaded vaccine in mice and dogs, respectively.

Conclusion

In the current study, for the first time, the adjuvanticity effect of green synthesized AgNPs on veterinary rabies vaccine potency with no in vivo toxicity was elucidated according to the European Pharmacopeia 8.0.

European consensus statement on leptospirosis in dogs and cats

Leptospirosis is a zoonotic disease with a worldwide distribution affecting most mammalian species. Clinical leptospirosis is common in dogs but appears to be rare in cats. Both dogs and cats, however, can shed leptospires in the urine. This is problematic as it can lead to exposure of humans. The control of leptospirosis, therefore, is important not only from an animal but also from a public health perspective. The aim of this consensus statement is to raise awareness of leptospirosis and to outline the current knowledge on the epidemiology, clinical features, diagnostic tools, prevention and treatment measures relevant to canine and feline leptospirosis in Europe.

Use of serologic tests to predict resistance to Canine distemper virus-induced disease in vaccinated dogs

The objective of the current study was to determine whether detection of Canine distemper virus (CDV)-specific serum antibodies correlates with resistance to challenge with virulent virus. Virus neutralization (VN) assay results were compared with resistance to viral challenge in 2 unvaccinated Beagle puppies, 9 unvaccinated Beagle dogs (4.4-7.2 years of age), and 9 vaccinated Beagle dogs (3.7-4.7 years of age). Eight of 9 (89%) unvaccinated adult dogs exhibited clinical signs after virus challenge, and 1 (13%) dog died. As compared to adult dogs, the 2 unvaccinated puppies developed more severe clinical signs and either died or were euthanized after challenge. In contrast, no clinical signs were detected after challenge of the 9 adult vaccinated dogs with post-vaccination intervals of up to 4.4 years. In vaccinated dogs, the positive and negative predictive values of VN assay results for resistance to challenge were 100% and 0%, respectively. Results indicate that dogs vaccinated with modified live CDV can be protected from challenge for ≤4.4 years postvaccination and that detection of virus-specific antibodies is predictive of whether dogs are resistant to challenge with virulent virus. Results also indicate that CDV infection in unvaccinated dogs results in age-dependent morbidity and mortality. Knowledge of age-dependent morbidity and mortality, duration of vaccine-induced immunity, and the positive and negative predictive values of detection of virus-specific serum antibodies are useful in development of rational booster vaccination intervals for the prevention of CDV-mediated disease in adult dogs.

Recent advances in canine leptospirosis: focus on vaccine development

Leptospirosis is a global infection of humans and animals caused by pathogenic Leptospira spp. Leptospirosis is a major zoonosis, with infection acquired from wild and domestic animals. It is also a significant cause of morbidity, mortality, and economic loss in production and companion animals. Leptospirosis in dogs is prevalent worldwide and as well as a cause of canine disease, it presents a zoonotic risk to human contacts. Canine leptospirosis does not differ greatly from the syndromes seen in other animal species, with hepatic, renal, and pulmonary involvement being the main manifestations. While the pathogenesis of disease is well documented at the whole animal level, the cellular and molecular basis remains obscure. Killed, whole-cell bacterin vaccines are licensed worldwide and have not changed greatly over the past several decades. Vaccine-induced immunity is restricted to serologically related serovars and is generally short-lived, necessitating annual revaccination. The appearance of new serovars as causes of canine leptospirosis requires constant epidemiological surveillance and tailoring of vaccines to cover emerging serovars. At the present time, there is no realistic prospect of alternative, non-bacterin vaccines in the foreseeable future.

Immunization with a recombinant subunit OspA vaccine markedly impacts the rate of newly acquired Borrelia burgdorferi infections in client-owned dogs living in a coastal community in Maine, USA

Background

In North America, Borrelia burgdorferi is the causative bacterial agent of canine Lyme borreliosis and is transmitted following prolonged attachment and feeding of vector ticks, Ixodes scapularis or Ixodes pacificus. Its prevention is predicated upon tick-avoidance, effective on-animal tick control and effective immunization strategies. The purpose of this study is to characterize dogs that are newly seropositive for Borrelia burgdorferi infection in relation to compliant use of a recombinant OspA canine Lyme borreliosis vaccine. Specifically, Preventive Fractions (PF) and Risk Ratios (RR) associated with the degree of vaccine compliancy (complete versus incomplete) are determined.

Methods

6,202 dogs were tested over a five year period in a single veterinary hospital utilizing a non-adjuvanted, recombinant OspA vaccine according to a 0, 1, 6 month (then yearly) protocol. Rates of newly acquired “Lyme-positive” antibody test results were compared between protocol compliant and poorly compliant (incompletely and/or non-vaccinated) dogs.

Results

Over the five-year span, one percent (range 0.39 - 1.3) of protocol compliant vaccinated, previously antibody negative dogs became seropositive for infection. Approximately twenty-one percent (range 16.8 – 33.3) of incompletely vaccinated dogs became positive for infection-specific antibodies. The Preventative Fraction for testing positive for antibodies specific for infection with Borrelia burgdorferi in any given year based on optimal vaccine compliance was, on average, 95.3% (range 93.29 - 98.08). The Risk Ratio for becoming infected with Borrelia burgdorferi antibodies in any given year if vaccine non-compliant was 21.41 (range 14.9 – 52.1). There was a high statistically significant relationship (p = <0.0001) in the observed data in terms of vaccination protocol compliance and the probability of Borrelia burgdorferi infection in each of the five years under study.

Conclusions

The recombinant outer surface protein A (rOspA) vaccine for dogs is highly effective in preventing new seropositive cases of Borrelia burgdoferi infection over a five-year period in dogs living in an endemic area. Dogs that were vaccine protocol-compliant were significantly less likely to become infected (as indirectly assessed by antibody) with the agent of canine Lyme borreliosis as measured by Preventive Fraction and Risk Ratio calculations.

Approaches to canine health surveillance

Effective canine health surveillance systems can be used to monitor disease in the general population, prioritise disorders for strategic control and focus clinical research, and to evaluate the success of these measures. The key attributes for optimal data collection systems that support canine disease surveillance are representativeness of the general population, validity of disorder data and sustainability. Limitations in these areas present as selection bias, misclassification bias and discontinuation of the system respectively. Canine health data sources are reviewed to identify their strengths and weaknesses for supporting effective canine health surveillance. Insurance data benefit from large and well-defined denominator populations but are limited by selection bias relating to the clinical events claimed and animals covered. Veterinary referral clinical data offer good reliability for diagnoses but are limited by referral bias for the disorders and animals included. Primary-care practice data have the advantage of excellent representation of the general dog population and recording at the point of care by veterinary professionals but may encounter misclassification problems and technical difficulties related to management and analysis of large datasets. Questionnaire surveys offer speed and low cost but may suffer from low response rates, poor data validation, recall bias and ill-defined denominator population information. Canine health scheme data benefit from well-characterised disorder and animal data but reflect selection bias during the voluntary submissions process. Formal UK passive surveillance systems are limited by chronic under-reporting and selection bias. It is concluded that active collection systems using secondary health data provide the optimal resource for canine health surveillance.