Comment by Hilift

Deet works on most things except deer flies. One bite is usually enough to itch for hours. They feed during the daytime.

"Their mouthparts include two pairs of cutting "blades" that lacerate skin and cause flow of blood out of the wound, which females lap up with a sponge-like mouthpart."

https://extension.entm.purdue.edu/publichealth/insects/taban...