midges are very tiny, almost
invisible flies that are related to mosquitoes and
other "gnats" in the family Ceratopogonidae. One
common name "no-see-ums" suggests their small size,
so small in fact that ordinary window screens don't
work to keep them out.
midges cause extremely itchy bites. In horses these
bites result in a condition called "sweet-itch".
Biting midges occur outdoors and do
not normally occur in houses. See the
following article for more details including the
impact of biting midges on horses and other
caption: biting midge (drawing)
... Control of Biting