I once arrived to a swamp that bordered plains, accidentally woke up abomination which then aggroed on a goblin in the plains. Goblins killed abomination, so I had to go to the plains to get the loot from it. There were 2 deathsquitos, so I just killed them with my lvl 2 bow (fully upgraded). But I guess they would one-shot if they could hit me, I only had bronze armour at the time. So just shoot them before they come close to you, and/or get better armour and food.