Biomaterial Database

Is canine heartworm (Dirofilaria immitis) endemic to South Australia? 2019

E J Dearsley, and R M O'Handley, and Cgb Caraguel

School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5371, Australia.

BACKGROUND Canine heartworm (Dirofilaria immitis) was reported as endemic to South Australia over 25 years ago, but the current status of canine heartworm infection in South Australia is unknown. METHODS We surveyed South Australian veterinary practices to collect evidence about canine heartworm cases, prevention, screening and treatment practices. RESULTS In total, 141 veterinary practices operating in South Australia (92.3% response rate) completed a 12-question telephone survey. Five confirmed cases of heartworm and one suspected false-positive case were reported from separate practices over the 2016-17 financial year. All confirmed cases had recently relocated to South Australia from interstate. Incidence of canine heartworm was estimated at 0.00% (95% confidence interval (CI): 0.00-0.0006) and prevalence at 0.002% (95%CI: 0.00-0.004) using conservative estimates of the South Australian dog population. Attitudes and protocols regarding heartworm differed significantly between metropolitan and rural veterinary practices. All metropolitan practices recommend systematic medicated prevention against heartworm, while some rural practices (20.7%) recommend prevention only when travelling interstate (P < 0.001). CONCLUSIONS Although there is a minor source of heartworm from introduction of infected dogs into South Australia, there is no evidence that the infection is transmitted to other dogs within the state. Therefore, it is unlikely that heartworm is currently endemic to South Australia as reported in the past. This new evidence provides a strong case to refine current prevention practices to reflect the current negligible risk of heartworm infection within South Australia.

UI	MeSH Term	Description	Entries
D011795	Surveys and Questionnaires	Collections of data obtained from voluntary subjects. The information usually takes the form of answers to questions, or suggestions.	Community Survey,Nonrespondent,Questionnaire,Questionnaires,Respondent,Survey,Survey Method,Survey Methods,Surveys,Baseline Survey,Community Surveys,Methodology, Survey,Nonrespondents,Questionnaire Design,Randomized Response Technique,Repeated Rounds of Survey,Respondents,Survey Methodology,Baseline Surveys,Design, Questionnaire,Designs, Questionnaire,Methods, Survey,Questionnaire Designs,Questionnaires and Surveys,Randomized Response Techniques,Response Technique, Randomized,Response Techniques, Randomized,Survey, Baseline,Survey, Community,Surveys, Baseline,Surveys, Community,Techniques, Randomized Response
D004183	Dirofilaria immitis	A filarial parasite primarily of dogs but occurring also in foxes, wolves, and humans. The parasite is transmitted by mosquitoes.	Dog Heartworm,Dirofilaria immitides,Dog Heartworms,Heartworm, Dog,Heartworms, Dog,immitis, Dirofilaria
D004184	Dirofilariasis	Infection with nematodes of the genus DIROFILARIA, usually in animals, especially dogs, but occasionally in man.	Heartworm Disease,Dirofilariases,Disease, Heartworm
D004283	Dog Diseases	Diseases of the domestic dog (Canis familiaris). This term does not include diseases of wild dogs, WOLVES; FOXES; and other Canidae for which the heading CARNIVORA is used.	Canine Diseases,Canine Disease,Disease, Canine,Disease, Dog,Diseases, Canine,Diseases, Dog,Dog Disease
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013021	South Australia	A state in south central Australia. Its capital is Adelaide. It was probably first visited by F. Thyssen in 1627. Later discoveries in 1802 and 1830 opened up the southern part. It became a British province in 1836 with this self-descriptive name and became a state in 1901. (From Webster's New Geographical Dictionary, 1988, p1135)
D015994	Incidence	The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases in the population at a given time.	Attack Rate,Cumulative Incidence,Incidence Proportion,Incidence Rate,Person-time Rate,Secondary Attack Rate,Attack Rate, Secondary,Attack Rates,Cumulative Incidences,Incidence Proportions,Incidence Rates,Incidence, Cumulative,Incidences,Person time Rate,Person-time Rates,Proportion, Incidence,Rate, Attack,Rate, Incidence,Rate, Person-time,Rate, Secondary Attack,Secondary Attack Rates
D015995	Prevalence	The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.	Period Prevalence,Point Prevalence,Period Prevalences,Point Prevalences,Prevalence, Period,Prevalence, Point,Prevalences