Hello there,
I am dr.milan an infectious disease specialist answering your question,
Horsefly can transmit some disease, but here it is not like that.
You have a bite lesion which is infected by some bacteria when it touched to floor or any other surface.
So, if your lesion is not much big than you need not to worry.
THis lesion is dripping so i suggest you go for culture examination of that fluid.
After tha start applying some
local antibiotic ointment like
soframycin 2 to 3 time a day.
And maintain proper hygiene of that part.
If your lesion is worsening or if you have symptoms like
fever and pain you need to consult your physician and go for examination.
Hope i have given appropriate guidance to you.
if you have any query you can consult me anytime.
Give me star rating according to your satisfactory level.
Thanking you.