A history of canine parvovirus in Australia: what can we learn?

Canine parvovirus (CPV) has been reported throughout the world since the late 1970s. Published information was reviewed to draw insights into the epidemiology, pathogenesis, diagnosis, treatment and outcomes of CPV disease in Australia and the role of scientific research on CPV occurrence, with key research discoveries and knowledge gaps identified. Australian researchers contributed substantially to early findings, including the first reported cases of parvoviral myocarditis, investigations into disease aetiopathogenesis, host and environmental risk factors and links between CPV and feline panleukopenia. Two of the world's first CPV serological surveys were conducted in Australia and a 1980 national veterinary survey of Australian and New Zealand dogs revealed 6824 suspected CPV cases and 1058 deaths. In 2010, an Australian national disease surveillance system was launched; 4940 CPV cases were reported between 2009 and 2014, although underreporting was likely. A 2017 study estimated national incidence to be 4.12 cases per 1000 dogs, and an annual case load of 20,110 based on 4219 CPV case reports in a survey of all Australian veterinary clinics, with a 23.5% response rate. CPV disease risk factors identified included socioeconomic disadvantage, geographical location (rural/remote), season (summer) and rainfall (recent rain and longer dry periods both increasing risk). Age <16 weeks was identified as a risk factor for vaccination failure. Important knowledge gaps exist regarding national canine and feline demographic and CPV case data, vaccination coverage and population immunity, CPV transmission between owned dogs and other carnivore populations in Australia and the most effective methods to control epizootics.

Canine parvovirus prevention-What influence do socioeconomics, remoteness, caseload and demographics have on veterinarians' perceptions and behaviors?

Canine parvovirus (CPV) is a cause of severe disease in dogs globally, yet is preventable by vaccination. A range of vaccination protocols are used by veterinary practitioners with evidence suggesting some protocols provide better protection than others in high infection-risk situations. This study investigated associations between veterinarians' vaccination recommendations and hospital remoteness, socioeconomic disadvantage, CPV caseload, and veterinarian perceptions and demographics. A national Australian veterinary survey in 2017 received 569 practitioner responses from 534 unique hospitals (23.6 % response rate). Respondents from major city hospitals had the lowest perceptions of the national CPV caseload (p < 0.0001). Those from hospitals with mild to moderate caseloads (6-40 cases per annum) recommended more frequent puppy revaccination - which is considered more protective - than those with the highest caseload (p = 0.0098), which might increase vaccination failure risk. Respondents from the most socioeconomically disadvantaged regions were over-represented in recommending annual revaccination of adult dogs; those from the least disadvantaged regions were over-represented in recommending triennial revaccination (p < 0.0001). Hospitals with higher CPV caseloads, greater socioeconomic disadvantage or increased remoteness did not favor two puppy vaccination protocols that are considered more protective (younger first vaccination age or older final vaccination age), despite these regions presenting higher CPV caseload risk. Titer testing to determine whether to revaccinate was more likely to be used in major city hospitals (p = 0.0052) and less disadvantaged areas (p = 0.0550). University of graduation was associated with CPV caseload, remoteness and level of socioeconomic disadvantage of the region where the graduate worked. University of graduation was significantly associated with age for final puppy vaccination and titer-testing recommendations. Graduates from one university were over-represented in recommending an earlier (10-week) finish protocol and titer testing, compared to all other universities. Year and university of graduation, and respondent's age were associated with a number of vaccination protocol recommendations suggesting that inherent biases might affect veterinarians' decisions. Emphasis on currently recommended vaccination protocols in undergraduate curricula and more protective vaccination protocol use in higher-risk regions could reduce immunization failure and CPV caseload.

Canine parvovirus prevention and prevalence: Veterinarian perceptions and behaviors.

Canine Parvovirus (CPV) causes severe morbidity and mortality in dogs, particularly puppies, worldwide. Although vaccination is highly efficacious in preventing disease, cases continue to occur and vaccination failures are well documented. Maternally derived antibody interference is the leading cause of vaccination failure and age at vaccine administration is a significant risk factor for failure. However, no studies have been performed on practicing veterinarians' usage of and compliance with published vaccination guidelines and label recommendations. Likewise, there are no published studies of veterinarian perceptions on CPV occurrence and mortality and its influence on case outcome. We report a study in which all Australian small companion animal (canine and feline) veterinary hospitals were surveyed, yielding a response rate of 23.5% (534 unique veterinary hospitals). Respondents overall perceived national CPV occurrence ten-times lower (median 2000 cases) than the estimated national caseload (20,000 cases). Respondents from hospitals that did not diagnose CPV perceived national occurrence twenty-times lower (median 1000 cases) than the estimated rate (p < 0.0001). Perceived disease mortality (50%) was 2.74 times higher than that reported (18.2%). In addition, 26.7% of veterinarians reported using serological titer testing to some degree, which some practitioners use in lieu of vaccination if a titer is perceived to reflect sufficient immunity. Based on this study veterinarians appear to be aware of the disease risk in their region but unaware of the burden of CPV disease nationally, and perceive mortality risk higher than it actually is. This might lead to an overestimation of cost to treat, and over-recommendation of euthanasia. Nearly half (48.7%) of respondents recommended final puppy vaccination earlier than guidelines recommend, while 2.8% of respondents recommended a puppy re-vaccination interval longer than supported by vaccine labels and guidelines. Both of these practices may put puppies at risk of CPV infection.

Are vaccine strain, type or administration protocol risk factors for canine parvovirus vaccine failure?

Canine parvovirus (CPV) is a highly contagious and worldwide cause of serious and often fatal disease in dogs, despite the widespread availability of vaccines. Which vaccine-related factors are associated with vaccination failure is largely unknown, and there are no reports from Australia. In this study - the first national population-level CPV study of its kind ever conducted - we analysed data on 594 cases of apparent CPV vaccination failure reported from an Australian national surveillance system to determine whether vaccine strain, type or administration protocol are risk factors for vaccination failures. The strain of CPV used in vaccine manufacture was not significantly associated with vaccination failure in clinical practice. The vaccine type (killed versus attenuated vaccine) for puppies diagnosed with CPV was associated with a lower mean age at time of vaccination (P=0.0495). The age at administration of the last CPV vaccination a puppy received prior to presenting with disease was a significant (P=0.0334) risk factor for vaccination failure, irrespective of whether the vaccine was marketed for a 10-week or 12-week or greater vaccination finish protocol. There was also a strong negative correlation between age at last vaccination prior to disease and vaccination failure (P<0.0001): the later a puppy received this last vaccination, the lower the risk of vaccination failure. This supports the hypothesis that the use of final vaccination in puppies at less than 16 weeks of age predisposes to vaccination failure and warrants a final age for vaccination recommendation to be at least 16 weeks for all canine parvovirus vaccines, especially in outbreak situations. The large number of cases identified in this study confirms that CPV vaccination failure is occurring in Australia. Veterinarians should consider CPV as a differential diagnosis in cases with appropriate clinical presentation, regardless of the reported vaccination status of the dog.

Epidemiology and clinical presentation of canine distemper disease in dogs and ferrets in Australia, 2006-2014.

OBJECTIVE: To determine the status and distribution of distemper in Australian dogs and ferrets. DESIGN: Retrospective case series. METHODS: Cases were identified via a national voluntary disease reporting system, veterinarian groups and a national laboratory database. The geographic distribution, seasonal distribution, signalment and clinical presentation of cases were described using maps and frequency distributions. RESULTS: A total of 48 individually affected dogs and ferrets in 27 case groups were identified, including eight confirmed case groups (> one individual). Confirmed cases were more common in summer and on the central coast of New South Wales and southern Victoria, and occurred exclusively in young, unvaccinated dogs. For dogs there was no obvious sex predilection. A mortality rate of 100% in ferrets and up to 77% in dogs was estimated. Neurological, gastrointestinal and respiratory were the most commonly reported systems affected in dogs and ferrets. There was no evidence that any large, unreported outbreaks occurred during the study period. CONCLUSIONS: Continuation of vaccination against canine distemper virus is justified within Australia, particularly for younger dogs. Veterinarians should continue to consider distemper in their differential diagnosis of cases with neurological, gastrointestinal and respiratory presentation.

Surveillance of upper respiratory tract disease in owned cats in Australia, 2009-2012.

Reported cases of feline upper respiratory tract disease (URTD) - presumptively diagnosed as feline herpesvirus (FHV) or feline calicivirus (FCV) - throughout Australia (2010-2012) were obtained from Disease WatchDog, a companion animal disease surveillance system. This surveillance system is based on voluntary reporting of cases by veterinarians, using a web-based program. Animal factors, location and vaccination information are also reported. Cases reported were mapped and seasonal patterns were described. A total of 131 FHV cases and 120 FCV cases were reported. Excluding euthanasia, case fatality rates were 1.12% and 1.28%, respectively. The largest proportion of cases was reported in winter. Young cats (≤ 2 years), intact cats, unvaccinated cats and (for FHV) male cats appeared to be over-represented in the cases reported. The distributions of cases reported in this surveillance system provide information to aid the diagnosis of infectious feline URTD and to develop client educational programs.

Distribution, seasonality and risk factors for tick paralysis in Australian dogs and cats.

Tick paralysis is a serious and potentially fatal condition of Australian companion animals induced by the paralysis ticks, Ixodes holocyclus and Ixodes cornuatus. Limited published information is available on the distribution, seasonality and risk factors for tick paralysis mortality in dogs and cats. This study describes 3479 cases of canine and feline tick paralysis in Australia using data extracted from a real-time disease surveillance program. Risk factors for mortality were identified, and maps of the distribution of cases were generated. Cluster analysis was performed using a space-time permutation scan statistic. Tick paralysis was found to be distinctly seasonal, with most cases reported during spring. Most cases were located on the eastern coast of Australia with New South Wales and Queensland accounting for the majority of reported cases. A cluster of cases was identified on the south coast of New South Wales. Dogs were found to be at significantly higher risk (P<0.05) of death if less than 6 months of age or if a toy breed. No significant risk factors for mortality were identified for cats. Some animals receiving chemoprophylactic treatment for tick infestation experienced tick paralysis during the products' period of effectiveness. There is a high risk of tick paralysis in dogs and cats on the eastern coast of Australia during the spring months. The risk factors for mortality identified can be used by veterinarians to determine prognosis in cases of canine tick paralysis and potentially to improve the treatment of cases. Daily tick searches of pets - particularly in high risk areas and during high risk periods - are recommended since the prevention of tick paralysis via chemoprophylaxis is not 100% guaranteed across the whole population.

Canine parvovirus in Australia: the role of socio-economic factors in disease clusters.

To identify clusters of canine parvoviral related disease occurring in Australia during 2010 and investigate the role of socio-economic factors contributing to these clusters, reported cases of canine parvovirus were extracted from an on-line disease surveillance system. Reported residential postcode was used to locate cases, and clusters were identified using a scan statistic. Cases included in clusters were compared to those not included in such clusters with respect to human socioeconomic factors (postcode area relative socioeconomic disadvantage, economic resources, education and occupation) and dog factors (neuter status, breed, age, gender, vaccination status). During 2010, there were 1187 cases of canine parvovirus reported. Nineteen significant (P<0.05) disease clusters were identified, most commonly located in New South Wales. Eleven (58%) clusters occurred between April and July, and the average cluster length was 5.7 days. All clusters occurred in postcodes with a significantly (P<0.05) greater level of relative socioeconomic disadvantage and a lower rank in education and occupation, and it was noted that clustered cases were less likely to have been neutered (P=0.004). No significant difference (P>0.05) was found between cases reported from cluster postcodes and those not within clusters for dog age, gender, breed or vaccination status (although the latter needs to be interpreted with caution, since vaccination was absent in most of the cases). Further research is required to investigate the apparent association between indicators of poor socioeconomic status and clusters of reported canine parvovirus diseases; however these initial findings may be useful for developing geographically- and temporally-targeted prevention and disease control programs.

Companion animal disease surveillance: a new solution to an old problem?

Infectious disease surveillance in companion animals has a long history. However, it has mostly taken the form of ad hoc surveys, or has focused on adverse reactions to pharmaceuticals. In 2006 a Blue Ribbon Panel was convened by the U.S. White House Office of Science and Technology Policy to discuss the potential utility of a national companion animal health surveillance system. Such a system could provide fundamental information about disease occurrence, transmission and risk factors; and could facilitate industry-supported pharmaco-epidemiological studies and post-market surveillance. Disease WatchDog, a prospective national disease surveillance project, was officially launched in January 2010 to capture data on diseases in dogs and cats throughout Australia. Participation is encouraged by providing registrants real-time disease maps and material for improved communication between veterinarians and clients. From January to mid-November 2010, an estimated 31% of veterinary clinics Australia-wide joined the project. Over 1300 disease cases - including Canine Parvovirus (CPV), Canine Distemper, Canine Hepatitis, Feline Calicivirus, Feline Herpesvirus, and Tick Paralysis - were reported. In New South Wales alone, 552 CPV cases in dogs were reported from 89 postcode locations. New South Wales data was scanned using the space-time permutation test. Up to 24 clusters (P<0.01) were identified, occurring in all months except March. The greatest number of clusters (n=6) were identified in April. The most likely cluster was identified in western Sydney, where 36 cases of CPV were reported from a postcode in February. Although the project is still in its infancy, already new information on disease distribution has been produced. Disease information generated could facilitate targeted control and prevention programs.

Effectiveness of a vegetable dental chew on periodontal disease parameters in toy breed dogs.

Sixteen toy breed dogs completed a parallel, 70-day two-period, cross-over design clinical study to determine the effect of a vegetable dental chew on gingivitis, halitosis, plaque, and calculus accumulations. The dogs were randomly assigned into two groups. During one study period the dogs were fed a non-dental dry diet only and during the second study period were fed the same dry diet supplemented by the daily addition of a vegetable dental chew. Daily administration of the dental chew was shown to reduce halitosis, as well as, significantly reduce gingivitis, plaque and calculus accumulation and therefore may play a significant role in the improvement of canine oral health over the long-term.

Setting global goals for oral health for the year 2010.

OBJECTIVE: To discuss the determinants for the possible setting of global goals for oral health for the year 2010. RESULTS AND CONCLUSIONS: If the application of oral health goals is to measure the outcome of oral health strategies and plans, they need to be substantially redesigned to reflect disparities in oral health and access to oral health care. It is no longer acceptable to focus only upon one or two arbitrarily selected disease entities and say these reflect the oral well-being of communities and the success (or failure) of oral health programmes. The use of validated socio-dental indicators to assess prevalence of socio-dental impacts seems essential, as does the avoidance of goals for conditions that are strongly influenced by culture, class, ethnicity and other widely variable local influences.

State disparities in the diagnosis and placement of pupils with learning disabilities.

We investigated the hypothesis that interstate disparities in the diagnosis of pupils with learning disabilities (LD) are more strongly correlated with demographic and sociopolitical factors than with the biological prevalence of the disability. We also investigated the relationship of these factors to placement practices. Thirteen independent variables representing state characteristics were simultaneously regressed against each of seven static dependent variables, measuring diagnostic and placement practices in 1989, and two dynamic dependent variables, measuring changes in practices between 1976 and 1989. Results of the regression indicated that although demographic and sociopolitical factors explained none of the total prevalence of the four most common physical disabilities (adjusted R2[R2] = 0), they did explain to a moderate degree the state prevalence of LD (R2 ranged from .15 to .28), and were more predictive still depending on measure of LD prevalence. Moreover, these same factors strongly predicted the extent to which states mainstreamed their pupils (R2 = .59) and the size of the nonmainstreamed cognitively disabled (LD and educable mentally retarded) population (R2 = .56).

Trends in the prevalence of dental caries in Israel.

This study's objective was to assess the prevalence of dental caries in five-year-olds and twelve-year-olds in Jerusalem, Israel. A total of 166 children comprised the younger group; and 147 children represented the twelve- to thirteen-year-olds. Examinations took place in the classrooms under natural lighting, using a mouth mirror and a probe. It was found that 27.7 percent of the younger children were caries-free, with a mean dif(t) value of 3.65 +/- 3.58. At the age of twelve years, only 4.8 percent were caries-free, with a mean DMF (T) value of 4.9 +/- 3.09. Nearly 58 percent of these carious permanent teeth had been treated. In Jerusalem, fluoridation of the water supply was implemented only recently. There are signs of increased public awareness of prevention methods.