Canine Dirofilariasis by Dirofilaria immitis “An emerging Zoonotic Infection” [A review article]

Dirofilariasis, commonly referred to as heartworm disease (HW), is a vector-borne zoonotic disease caused by Dirofilaria spp. It is a chronic and life-threatening cardiopulmonary disease predominantly affecting the stray dog population. The causative agent, Dirofilaria immitis, is transmitted by mosquitoes of the Aedes, Anopheles, and Culex genera and causes significant morbidity and mortality in infected animals. In Pakistan, the large population of stray dogs, particularly in rural and underdeveloped regions, remained neglected and subjected to mistreatment, leads to a high burden of parasitic infestation, including Dirofilariasis. Among the 27 species of Genus Dirofilaria species, Dirofilaria (D.)immitis is the most important due to its severe pathological effect and higher prevalence in dogs. The prevalence in India, Iran, China and Bangladesh - neighboring countries of Pakistan - is 22.08%, 5.4%, 7.4% and 50.0%, respectively. Other than dog, D.immitis can infect 30 species of animals includes wild cats, ferrets and wild canids. HW produces intense pulmonary vascular and parenchymal diseases which can lead to congestive heart failure, which may ultimately result in the victim's death. Dirofilariasis is believed to be emerging due to global warming, climate change and persistent movement of heartworm. Major diagnostic approaches includes Modified Knott’s technique, PCR and ELISA. Treatment for this infection includes two approaches, either medical or surgical or both depending upon severity. The main objective of this review is to assess the prevalence and current distribution of canine Dirofilariasis in neglected areas in comparison with the globe. In addition, the current review aimed to assess possible diagnostic procedure and therapeutic protocols of Dirofilariasis.