Mosquitos may be small, but they're by far the deadliest animals on the planet. In fact, this tiny insect is more dangerous to the human race than sharks, wolves, lions and crocodiles put together. They kill hundreds of thousands of people every year, spreading deadly diseases like malaria and dengue fever through their bites.
Over the years several methods of prevention have been developed, from chemical mosquito repellents to mosquito nets. Now, scientists are trialing a new approach, which involves intentionally infecting mosquitos with bacteria and then releasing them into the wild – turning the root of the problem into the solution.
The researchers will release 40,000 mosquitos over a four-month period in a bid to reduce cases of dengue fever in Rio de Janeiro in Brazil. The mosquitos have been infected with intracellular bacteria called Wolbachia, which suppresses the dengue fever by preventing the virus from multiplying. The Wolbachia is then passed down to the mosquito’s offspring during reproduction.
If a bacteria-carrying male tries to fertilise eggs from a non-contaminated female, the eggs will not turn into larvae. Only when the female carries the Wolbachia too will the male be able to reproduce, ensuring all of its offspring inherit the virus-suppressing bacteria. Eventually all future generations of mosquito will contain Wolbachia, reducing the number of mosquitos carrying dengue fever, and thus reducing the number of people infected.
So with advances like these, the reign of the world’s deadliest animal may soon come to an end.
Watch Factpack: Bacteria to learn more about bacteria.