It spends its larval stage in the weedbeds of slow flowing rivers and when the fly emerges, the female seeks a blood meal before mating.

[2] In a four-week period during the spring of 1972, some 600 people were estimated to have visited their doctors in Blandford to be treated for insect bites.

They suggested using a biological, bacterial insecticide, Bacillus thuringiensis israelensis (Bti), which was sprayed into the weed beds, resulting in the destruction of 80–90% of the Blandford fly larvae and a corresponding reduction in the numbers of people bitten.

[5] Recently, the fly has begun affecting people in other parts of southern England, including built up areas, probably encouraged by garden water features.

The Blandford fly has been recorded in the following countries: Czech Republic, Denmark, Finland, France, Latvia, Germany, Austria, Belarus, Belgium, Southern England, Italy, Lithuania, Luxembourg, Netherlands, Norway, Poland, European Russia and Western Siberia, Slovenia, Sweden, Turkey, and Ukraine.