Where I live they’re common, they’ll get big and they’ll give you a start maybe but that’s as much of a threat as they’ll ever be. They’re clumsy fliers for the most part so they won’t surprise you. Mosquitos themselves are more of a problem. If you leave it be, it’ll leave you be. They don’t like humans. The worst they’re capable of is buzzing you in a coincidental fly-by.
Again if it’s the bug I’m familiar with, they’re your friend. Don’t kill it.