Everyone knows animals are dangerous. But which kill the most people? Not sharks. Nor other humans, either, according to a tally completed by Bill Gates at his blog GatesNotes.com. Sharks are responsible for a mere 10 human deaths a year on average, he says.
Crocodiles account for 1,000 fatalities. Snakes? About 50,000. Humans – and this seems a low score, frankly – 475,000. The deadliest of all, however, is the whirring assassin, the mosquito. (See graphic, below.)
There are 2,500 mosquito species, populating every corner of the world apart from Antarctica. “During the peak breeding seasons, they outnumber every other animal on Earth, except termites and ants.” As part of series of posts on these deathly couriers of malaria and dengue fever, the Microsoft founder, as part of his work for his Gates Foundation, travels to Indonesia, where he dips his bare arm into “a cage full of hungry mosquitoes so they can [can] feed on my blood”.
I got the request during a stop at Gadjah Mada University in Yogyakarta to check in on an amazing project to control the spread of dengue …
Researchers at the university are part of a global effort exploring whether a bacterium called Wolbachia can be used to control dengue. Wolbachia occurs naturally in 70% of all insects, and it is harmless to humans. But it can block the transmission of dengue by mosquitoes. Unfortunately, the type of mosquito that carries dengue, Aedes aegypti, doesn’t naturally get Wolbachia, but one group of scientists discovered a way to infect them with it. Now, in partnership with other researchers around the world, they’re raising a colony of Wolbachia mosquitoes to be released in hopes that they will breed with wild mosquitoes and curb the spread of dengue …
In January, with the support of the government and residents, the Indonesian team began releasing Wolbachia mosquitoes in neighborhoods around Yogyakarta. … Many more of these amazing mosquitoes will need to be released into the wild in the months ahead before we can assess the impact of this project. That means the university’s research team will be busy breeding and raising thousands of Wolbachia mosquitoes. I have a lot of admiration for the members of the research team. Every week they take turns having their arms feasted on by several hundred very hungry female mosquitoes who need human blood to develop their eggs. There’s no risk of getting dengue from these lab-reared mosquitoes, but the bites itch just the same.
I learned that first hand when I agreed to offer a cage of mosquitoes a taste of my own blood. Within just a few minutes my arm swelled up with dozen of bites. It was a small price to pay for an amazing project that has the potential to turn the tide against a terrible disease.
See also: Five animals that look like politicians