A miniature drone that is faster and more agile than mosquitoes. Equip it to detect a single mosquito in the room. When in need, release the killer drone, wait for it to clear the room, and go back to sleep.
Few things are worse than being awoken by a mosquito buzzing around your head in the middle of the night. A dilemma awaits you: either you get up and look for it in vain or you accept the fact that it will feed on you.
Not die from malaria, dengue fever, etc.
Mount an additional rotor to the front side of the drone. When it almost catches up with the mosquito, activate the front-facing propeller and use it to gain speed and ram into + mince the mosquito.
The drone could recharge itself by landing on an induction charger. That way it could permanently remain on patrol.