Photo By International Atomic Energy Agency / CC BY-SA 4.0

The Deadliest Disease Carried by a Bug

The Tsetse Fly (pronounced SEET-SEE) is a type of fly that lives in most of Africa. This insect is an extremely large type of fly that live by feeding on the blood of other animals, including even humans! These flies have been studied extensively by scientists because of their role in transmitting disease. This bug is not the most dangerous bug because of a poison it contains, or a powerful bite. It is the most dangerous because of what diseases it spread, how it spreads them, and how quickly it is able to spread those diseases. These flies produce up to 31 groups of larvae every year, with each brood of larvae being about 7 - 10 larvae.

Like most other insects, the Tsetse Fly has a body made up of three very distinct parts. They have two extremely large eyes, and a very distinct, only found in these bugs, forward-pointing proboscis underneath their head. This proboscis is what they use to suck the blood from whatever mammal they have chosen for their next meal. They don't just take a small amount of blood from each mammal either. When a Tsetse Fly has discovered the mammal it wants to feed on, it will stay on that creature for as long as it can without getting swatted away, or until it is full. If it is able to stay until it is completely full of blood, it will have consumed so much blood that a sack in the back of its abdomen will grow to be the same exact size of the fly, only it's filled with blood. That's right, as the fly sucks your blood it doesn't digest it. It instead takes it and stores it in a sack in its abdomen that can make the fly almost double in size. Another thing that makes these flies different than other flies is their toughness. Unlike the common house fly that can be killed with a fly swatter, it takes a tremendous amount of force to crush one of the Tsetse Flies.

The Tsetse Fly are thought to be a huge huge reason why in Saharan Africa they have rural poverty. This is because they are thought to have prevented mixed farming. Any land infested wth the Tsetse Fly, which is almost all land in Sahara Africa, has to be cultivated by humans using hoes, instead of by animal and plow. This is because these flies carry a disease called nagana that, if bitten, will slow and weaken the animal carrying the plow, and eventually in most cases kill it. However, not all hope is lost. There are some cows that are able to survive the diseases spread from the Tsetse Fly. Unfortunately though, these cows that do survive produce much less milk, pregnant cows always have abortions, and they produce much less manure as well.


Source: “Tsetse Fly.” Wikipedia, Wikimedia Foundation, 4 June 2018,