Seroprevalence of canine heartworm disease in Kerman, southeastern Iran

Abstract

Canine dirofilariosis is presumed to be enzootic in different parts of Iran but no study has been done regarding the prevalence of canine dirofilariosis in southeastern Iran. In this study, the presence of Dirofilaria immitis circulating antigen was detected using a commercial immunochromatogeraphy kit in the sera of 100 owned dogs, which were referred to Kerman Veterinary Hospital during a 6-month period. Modified knott test and follow-up radiography and electrocardiography were performed to support the heartworm diagnosis in seropositive dogs. At the same period, 98 stray dogs were subjected to post-mortem examination of the heart, pulmonary arteries, thoracic venae cavae, and lungs for detection of adult heartworm infection. The overall seroprevalence of heartworm was estimated at 5% but only two seropositive dogs showed microfilaremia. No stray dog was infected at necropsy and all seropositive dogs were owned. The prevalence of heartworm disease showed an initial increase with age fallowed by a decline in dogs older than 6 years. There were no significant differences among the dogs regarding sex and breed. Seven infected dogs (70%) were symptomatic in physical examination, and a broad spectrum of specific clinical signs of cardiovascular involvement was noticed. Distinctive radiographic signs with varied degrees of severity were seen in 50% of cases. Electrocardiography of seropositive cases revealed specific signs of right-sided cardiomegaly in 30% of cases. In conclusion, Kerman is a low endemic area for canine dirofilariosis but further epidemiological researches are needed to identify the disease distribution and human cases in southeastern Iran.