Molecular Epidemiology of Canine Heartworm (Dirofilaria immitis) in Culex pipiens Mosquitoes Collected from Tehran

Dirofilaria immitis is a nematode parasite that inhabits and develop within the heart and pulmonary arteries of canids, felids, and also humans. The microfilariae of this parasite circulate in the bloodstream and are transmitted to new hosts through the bites of Culex pipiens mosquitoes. Culex pipiens, commonly known as the common house mosquito, is a native urban pest species. Since the early 20th century, various control campaigns have been implemented across European countries targeting this species. It exhibits high ecological plasticity, resulting in complex feeding behaviors and vector potentials. This study was conducted from June to September of 2024 in Tehran. A total of 100 Culex pipiens mosquitoes were collected from different areas of the city and examined Dirofilaria immitis infection using molecular methods (PCR). The results showed that 15 of the collected mosquitoes were positive for D. immitis microfilariae. Given the infection rate observed in this study, the high potential for infection in the studied areas, and the importance of D. immitis associated disease, implementing hygienic measures in mosquito prone areas and dog shelters, along with effective mosquito control, especially in humid regions during warm seasons, will be essential to prevent the spread of this zoonotic disease among dogs and humans.