Three courses of antibiotics in the last few years because of these little bastards. Apparently they land on clothing then crawl in or onto skin so you can’t feel them. They then try to excise a piece of skin to take away and feast on. In doing so, they chew loads of crap from your skin and their mandible into you, hence the much worse infection than a mozzie bite. Muddy mtb legs make this worse, and you have less chance of feeling them if your legs are caked in mud too.
Get to the quack for some antibiotics quick.
They are one of the few species I would happily see go extinct.
On a slightly different tack, apparently if you find a mozzie on a loose part of your skin, you can pinch the skin up and trap the little buggers mouthparts, but they cannot stop the flow of blood, so they swell up ans eventually burst! A suitably revolting end.