W. magnifica larvae cause myiasis in mammals, mainly in sheep, but also in cattle, goats, horses, and rarely in humans.
In sheep, larvae chiefly infest genitalia or open wounds.
W. magnifica is found in southern Europe, Central Asia, the Middle East, North Africa, and China.
[5] Their range is increasing, believed to be because of the spread of intensive sheep rearing.
The larvae of the North American species, W. vigil and W. opaca, are incapable of penetrating adult skin; infestation occurs only in infants.