Pesticide?

I don´t mind too much giving my blood to mosquitoes. But the one(s) that got me Sunday night were really either mean or somehow infected.
The two stitches in my legs are getting better but my arm is still red, hot and swollen over a really large area.

I got another stitch in the middle finger, right in the fingertip which hurts when I touch something with it (keyboard, for example...).
There went a really mean one in the little finger, right underneath the nail where the finger can not swell. The skin is bending and that hurts. Plus it´s itching like crazy.
I even got one in the face! I look like I just come from the dentist.
Did I interrupt the stupid insect or were there so many and why does Ingo always go away without even a "test-stitch"?

I read they smell if they like the person´s blood. Unluckily they didn´t write if there is something you can eat (garlic? Ok, but that would keep Ingo away, too, I guess...) or drink to keep them away.
I have insect screening installed so where is the hole? Or do they sneak through the door?
I bet those mossies are infected, just where from - I live in a town not a village where they could get it from the farmers´ fertilizers...
Scary, somehow.