Dirofilaria repens - Anterior end of an adult

France, Basset Didier

Dog filariae (100 to 170 mm long and 500 μm in diameter). The anterior extremity shows a bare mouth and a  vulvar orifice located at 1.5 mm. It is transmitted by an  infected mosquito belonging to the genus Aedes. It can also contaminate the subcutaneous tissues of human, where it develops to an immature adult stage. The worms fail to reach adulthood while infecting human body.