Tsetse Fly
This is one of the most dangerous animals in the world, and definitely one of the most dangerous flies. Even though it only grows to the size of a common housefly, it can kill a human. They mainly lurk in Sub-Saharan Africa. Similarly to mosquitos, they suck the blood of human beings and deliver diseases such as Trypanosomes, a parasite. Unfortunately, there are no cures for this parasite, so if you happen to get it, you’re out of luck.

The parasite is the main cause of African Sleeping Sickness, which is a disease affecting the nervous system of humans, and thus disrupting sleep patterns. The disease can also be fatal, so it’s best to avoid getting bitten by this fly altogether. Some people, they develop a skin rash after a bite from the fly, but aching muscles, fever, and headache are also common symptoms (Flamingoof).