Vaccination is considered the most successful health measure both in human medicine and in veterinary practice. International guidelines of the vaccination of cats and vaccination experts (WSAVA, AAFP, ABCD) recommend that, whenever possible, all dogs and cats receive the benefit of vaccination. This not only protects the individual animal but provides optimum ‘herd immunity’ that minimizes the likelihood of infectious disease outbreaks [1, 2, 4, 17].
This study aimed to understand factors influencing the Italian cat owners’ opinion about vaccination. The very high percentage (90.7%) of the owners that had taken their cats for vaccination to a veterinarian at least once showed Italian owners’ trust in cats’ vaccination. The high percentage (80%) of owners that had their cat recently vaccinated within a three-year interval was in line with the 77.9% of recently vaccinated cats in Germany [7]. Our results were not comparable with the 69% of vaccinated cats in the UK because the interval was set in the preceding 12 months in the English study [16]. The three-year interval was used in this study to differentiate the recently vaccinated and the not recently vaccinated groups of cats. It has to be reminded that the general three-year interval recommended for core vaccination by the current guidelines may not be always adequate and needs to be considered depending on the vaccine and cats’ lifestyle, as previously observed [1, 7, 18, 19].
Due to the high percentage of recently vaccinated cats and the low percentage of not adequately vaccinated animals (not recently vaccinated and unvaccinated cats), our results suggest that the cat population of this study may be well protected (considering the aforementioned “herd immunity” concept). However, it has to be reminded that a recent vaccination may not necessarily imply that the cat has protective immunity [20]. Our results also suggest that the non-vaccination movement that has been reported in Italy in human medicine is apparently not a problem in veterinary medicine as it is likely not present at the moment among pet owners.
When analyzing all the variables of this study, some were not included in the final model because they were correlated (e.g. owners that go more often to the veterinary also vaccinate more often) or did not improved the fit of the model.
Regarding the results from the multinomial logistic regression, the likelihood of recent vaccination being higher in cats between 2-4 years was surprising but was in accordance with a previous study [7]. The need to clarify with owners the necessity of vaccination in kittens starting at the age of 6-8 weeks and following thereafter the recommendations for a strong immunity is of paramount importance considering that our results also showed that young cats (8 weeks-1 year of age) tended to be associated with the unvaccinated status. However, the result may be biased by the low number of young cats analyzed in this study compared to older cats and by the three-year interval that may augment the number of cats > 1 year of age included in the recently vaccinated group, explaining the higher likelihood of 2-4 years old cats recently vaccinated.
The less common recent vaccination status in older cats agrees with previous findings [7], and may be explained by the importance of cats’ age in the decision to vaccinate cats that was a variable associated with the not recently vaccinated group. However, the significant impact of cats aged 5-9 years on the vaccination status needs to be carefully evaluated because the significant older age of cat in the not recently vaccinated group may be biased by the three-year interval vaccination and therefore by the fact that cats within this group are surely more than 3 years and 8 weeks old. When excluding the not recently vaccinated group, older cats tended to be associated with the unvaccinated status, confirming the likely negative impact of older age on the vaccination status. Therefore, owners might think that older cats do not need vaccination, because of a long-lived immunity following vaccination and a higher protection against infectious disease. However, since old cats are known to have the same risk of infectious disease as younger cats and ageing is associated with a decline in functional competence of the immune system, regular boosters are recommended for cats, regardless of their age [1, 2, 4, 21].
Our analysis also showed that the annual household income had a significant impact on the vaccination status. Indeed, the likelihood of a recent vaccination status was significantly higher in cats with owners with a higher annual household income whereas not recently vaccinated cats and unvaccinated cats were significantly associated to a lower household income. The annual household income has not been reported previously as a factor affecting the vaccination status of cats in the UK and in Germany [7, 16]. This may be explained by the fact that Italian owners are accustomed to pay for all veterinary services whereas 40% of cats have health insurance in the UK and the insurance covers most of veterinary services [16]. Moreover, the median household income in Italy is lower compared to Germany and the UK [22], and payment of veterinary services, including vaccinations, may be troublesome, especially for owners with lower household income. The economic factor may have also accounted for the significantly higher likelihood of cats being unvaccinated among owners who perceived cost of vaccination an important factor. The importance of cost of vaccination has been previously reported to be associated with the unvaccinated status of cats in the UK [16]. Economic data should be carefully considered in the future due to the economic loss linked to the COVID-19 pandemic that may also reduce the likelihood of cats’ vaccination.
Concerning the likelihood of recent vaccination status, the significantly higher recent vaccination status among cats from breeders or pet shops compared to other cats was not surprising. High purchase price could lead owners to be more prompt to vaccination. The majority of cats from breeders and pet shops are purebred cats and the higher percentage of purebred cats was correlated to Italian owners that had decided to recently vaccinate their cat. Our results are in accordance with the more common recent vaccination records in purebred cats compared to shorthair cats in Germany [7]. Our results did not confirm the likelihood of a vaccination status higher in cats that had traveled abroad, visited a cat show or a cattery. These factors have been associated with the requirement of up-to-date vaccinations and European Pet Passport with vaccination against rabies to travel within Europe and are usually more common in purebred cats [7, 16]. Our results may be explained by the lower presence of purebred cats in our data compared to previous studies [7].
The lower importance of cat’s stress and the higher perception of vaccination efficacy reported in owners of recently vaccinated cats, even if not statistically significant, may also explain their willingness to vaccinate their cats.
The likelihood of not recent vaccination status was significantly higher in owners that perceived the lifestyle of cats as an important factor. This result is likely linked to the higher frequency of indoor lifestyle only in cats belonging to the not recently vaccinated group compared to unvaccinated cats, that tended to be an important factor associated to the decision on the vaccination status of cats. This result suggests that owners of these cats might have assumed that animals living for prolonged periods in closed environments with no contact with other cats were not at risk and did not need revaccination. However, European guidelines recommend vaccination booster every three years also for cats living indoor-only, except for FPV that may be administered every three years or more [18]. Veterinarians should consider this result and, to improve the vaccination status of cats, education of owners is required on the importance of adequate vaccination protocols and boosters also for cats living indoor-only.
The likelihood of unvaccinated status higher in owners with a lower frequency of health-related jobs, such as doctors, nurses or pharmacists, was not surprising. This result may also be linked to the lower level of education that was observed in the owners of the unvaccinated cats. Our results suggest that jobs not related to health-aspects and lower education levels may be associated with little knowledge on scientific aspects, including the importance of vaccination, and therefore the higher unvaccinated status of cats is more likely.
The likelihood of an unvaccinated status tended to be associated with owners being 21-49 years old. Despite this is not being a significant data, it is interesting to keep on monitoring this aspect because non-vaccination movements in Italy have been more frequently reported among people aged 25-44, even if not significantly, and significantly in people with a lower level of education [23].
The importance of factors preventing owners from having their cats vaccinated, such as cats’ capture, travel to the veterinarian and inappropriate waiting times, may be related to the lower perception and knowledge of importance of vaccination. Therefore, it is likely that owners of unvaccinated cats consider taking the cat to the veterinarian not necessary for their cat’s health. Indeed, such factors have been considered not important by a high percentage of owners of recently vaccinated cats, followed by owners of not recently vaccinated cats. Moreover, the lower compliance of owners of unvaccinated cats with veterinary advice for vaccination and the lower importance for cats’ susceptibility to infectious disease compared to the owners of vaccinated cats, even if not statistically significant, may also explain why owners of unvaccinated cats do not understand the need of vaccination in cats.
This study showed that Italian cats’ owners have a good level of confidence in veterinarians. The majority of owners reported the importance of veterinary advice and considered veterinarians as the main source of information for their cats’ health. More than half of respondents (58,8%) followed their veterinarian recommendation for annual vaccinations, which was surprising, as not in line with guidelines. Annual vaccination is recommended for some of the non-core vaccines, such as feline leukaemia virus (FeLV) in high risk cats, Chlamydophila (Chlamydia) felis and Bordetella bronchiseptica (vaccine not available in Italy) and might also apply for feline herpesvirus (FHV-1) and feline calicivirus (FCV) in high-risk situations [1, 2, 4]. However, the majority of cats of this study lived indoors (63,5%) and several lived in a single-cat household (31,1%), situations in which annual booster is not necessary. Recommendation of annual vaccination was recently reported also in German cats [7], and was suggested to be associated to lack of knowledge of feline vaccination guidelines or economic considerations.
Results on the knowledge of antibody test to evaluate vaccination status and avoid unnecessary boosters showed that respondents who had vaccinated their cats were more aware of it and owners of recently vaccinated cats were more inclined to use it in the future than other owners of cats. However, even if the minority of cats’ owners were aware of this test before reading the questionnaire, most respondents were inclined to use it in the future suggesting that owners’ decision also rely on their personal knowledge of other laboratory approaches.
Overall, the web-based questionnaire allowed us to include both vaccinated and unvaccinated cats because it was not spread among veterinarian practices. Moreover, online survey and social networks approach was a cheap and efficient way for obtaining data across a huge area in a short time: 83,8% of respondents found out about the questionnaire through the web.
Despite internet access was a requirement for participation, it likely did not introduce a bias in the study because according to the Italian office of statistics, the majority (65.3%) of the Italian population uses internet [24]. It is also likely that publicity conducted via social media network may have not introduced a bias towards owners that were more interested in cats and cats’ health and more prone to vaccination. Indeed, our study confirmed that information on health status of cats is also obtained online by the majority (70.8%) of pet owners, regardless of compliance with vaccination of their cats [25]. However, considering the nature of internet-based surveys and publicity conducted via social media networks, there is the possibility that the sample acquired in this study was not truly representative of the general pet owner population. Indeed, females have been reported to be more incline to answer questionnaires and use social networks than males in Italy and this may have accounted for the high prevalence of female respondents observed in this study.
Therefore, our results should be interpreted taking into consideration the possible limitations of this study. The sample of cat owners responding to the survey was based on self-selection and this may have also introduced the gender bias observed in our study and may have accounted for the high percentage of people aged 21-49 years of age in the population of respondents.
Even if greater than predicted, considering the high prevalence of female respondents in previous studies [7, 16], the strong bias towards female pet owners was in line with a recent study based on a questionnaire disseminated online to English-speaking pet owners regarding pet nutrition [26]. Considering that females are reportedly more likely to keep pets than males, the results of our study may be indicative of the general cat owner population [16, 26-28]. However, female have been reported to have higher empathy towards animals, be more interested in health-related topics and carry the primary responsibility for pets’ healthcare compared to males and this may have increased the proportion of vaccinated cats compared to previous studies [16, 29].
Cat owners aged 21 to 49 years participated in the questionnaire more than owners in other age groups, probably reflecting the common use of the internet by younger owners compared to the elderly.
Finally, as previously reported, questions to confirm recipients understanding of the word “vaccination” were not asked in our study and whether the participants in the survey completely understood what vaccination was and if they could differentiate it from other procedures performed by veterinarians is not known. It is possible that this may represent another possible limitation of this study [16].