2013 update on current vaccination strategies in puppies and kittens

Filgrastim Efficiency in Cats Naturally Infected with Feline Panleukopenia Virus

Feline Panleukopenia (FPL) infection is caused by feline panleukopenia virus (FPV), and it is considered one of the most severe cat's infectious diseases. Since there is no specific antiviral treatment for FPL, the therapeutic protocol usually is focused on fluid therapy and supportive care. However, filgrastim, a granulocyte colony-stimulating factor (G-CSF) used in human medicine to treat neutropenia and leukopenia, has been lately used in treating FPV disease, providing promising results. During January 2022 and September 2024, twenty-two cats diagnosed with feline panleukopenia virus were subjected to filgrastim (Zarzio®, Sandoz, Kundl, Austria) administration at a dose of 6 µg/kg for 3 consecutive days. The 4th day was a break day, and in the 5th day, the complete blood count was repeated. White blood cells, lymphocytes, monocytes, neutrophils and eosinophils parameters improved after Zarzio® administration, with a significant statistical difference (p < 0.01) when their values between day 1 (pre Zarzio® administration) and day 5 (post Zarzio® administration) were analysed. However, red blood cells, haemoglobin, haematocrit and platelets parameters registered a considerable reduction from day 1 to day 5 with a significant statistical difference (p < 0.01), considered as post-administration side effects. In our study, the survival rate following Zarzio® administration was 100%, suggesting that the protocol involving three doses is effective in restoring the leukopenia and neutropenia.

Safety of a Novel Listeria monocytogenes-Based Vaccine Vector Expressing NcSAG1 (Neospora caninum Surface Antigen 1)

Listeria monocytogenes (LM) has been proposed as vaccine vector in various cancers and infectious diseases since LM induces a strong immune response. In this study, we developed a novel and safe LM-based vaccine vector platform, by engineering a triple attenuated mutant (Lm3Dx) (ΔactA, ΔinlA, ΔinlB) of the wild-type LM strain JF5203 (CC 1, phylogenetic lineage I). We demonstrated the strong attenuation of Lm3Dx while maintaining its capacity to selectively infect antigen-presenting cells (APCs) in vitro. Furthermore, as proof of concept, we introduced the immunodominant Neospora caninum (Nc) surface antigen NcSAG1 into Lm3Dx. The NcSAG1 protein was expressed by Lm3Dx_SAG1 during cellular infection. To demonstrate safety of Lm3Dx_SAG1 in vivo, we vaccinated BALB/C mice by intramuscular injection. Following vaccination, mice did not suffer any adverse effects and only sporadically shed bacteria at very low levels in the feces (<100 CFU/g). Additionally, bacterial load in internal organs was very low to absent at day 1.5 and 4 following the 1st vaccination and at 2 and 4 weeks after the second boost, independently of the physiological status of the mice. Additionally, vaccination of mice prior and during pregnancy did not interfere with pregnancy outcome. However, Lm3Dx_SAG1 was shed into the milk when inoculated during lactation, although it did not cause any clinical adverse effects in either dams or pups. Also, we have indications that the vector persists more days in the injected muscle of lactating mice. Therefore, impact of physiological status on vector dynamics in the host and mechanisms of milk shedding requires further investigation. In conclusion, we provide strong evidence that Lm3Dx is a safe vaccine vector in non-lactating animals. Additionally, we provide first indications that mice vaccinated with Lm3Dx_SAG1 develop a strong and Th1-biased immune response against the Lm3Dx-expressed neospora antigen. These results encourage to further investigate the efficiency of Lm3Dx_SAG1 to prevent and treat clinical neosporosis.

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.

Enteropathogen infections in canine puppies: (Co-)occurrence, clinical relevance and risk factors

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CPV, CCoV and β-hemolytic E. coli are associated with (severe) acute diarrhoea in puppies.

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Puppies from high-volume breeders are more likely to be infected with CPV, CCoV and Cystoisospora spp.

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CPV and CCoV are more often detected in winter/spring.

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Multiple enteric infections are common in puppies with and without diarrhoea.

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Screening of CPV, CCoV and β-hemolytic E. coli is advised in diarrhoeic puppies.

Laboratory confirmation of the causative agent(s) of diarrhoea in puppies may allow for appropriate treatment. The presence of potential pathogens however, does not prove a causal relationship with diarrhoea. The aim of this study was to identify specific enteropathogens in ≤12 month old puppies with and without acute diarrhoea and to assess their associations with clinical signs, putative risk factors and pathogen co-occurrence. Faecal samples from puppies with (n = 113) and without (n = 56) acute diarrhoea were collected and screened for Canine Parvovirus (CPV), Canine Coronavirus (CCoV), Salmonella spp., Campylobacter spp., Clostridium perfringens, Clostridium difficile, β-hemolytic Eschericha coli (hEC), Giardia spp., Toxocara spp., Cystoisospora spp., and Cyniclomyces guttulatus. One or more pathogens were detected in 86.5% of diarrhoeic puppies and in 77.8% of asymptomatic puppies. Significant positive associations were found between CPV and CCoV, CPV and Cystoisospora spp., Toxocara spp. and hEC, Giardia spp. and C. guttulatus. Only CPV and CCoV were significantly associated with diarrhoea, hEC with a subset of puppies that had diarrhoea and severe clinical signs. CPV was more prevalent in puppies under 3 months of age. Puppies from high-volume dog breeders were significantly at increased risk for CPV (OR 4.20), CCoV (OR 4.50) and Cystoisospora spp. (OR 3.60). CCoV occurred significantly more often in winter (OR 3.35), and CPV in winter (OR 3.78) and spring (OR 4.72) as compared to summer.

We conclude that routine screening for CPV, CCoV and hEC is recommended in puppies with acute diarrhoea, especially if they are under 3 months of age and originate from high-volume dog breeders. Routine screening for other pathogens may lead to less conclusive results.