Infecting mosquitos seems to be a counterintuitive way to fight any disease, but those who understand dengue fever know that this could be a major breakthrough in fighting the disease. Dengue or breakbone fever is caused by the dengue virus which is typically transmitted by mosquito. Symptoms of the disease include high fever, similar in appearance to measles. The fever can result in death, brain damage, and scarring. Each year, more than 50 million people in more than 100 countries fall sick with dengue fever and 20,000 die from the disease.
Dengue fever is transmitted by several species of immunity to the victim for only that type of the virus, but it can give short-term immunity to the other three types of the virus.
Presently, there is no vaccine for dengue fever, making it necessary to focus on prevention. This is usually done by reducing the habitat for mosquitoes and limiting potential victims’ exposure to mosquito bites. Recently, however, a group of Australian researchers think they can slow the spread of the disease among humans by preventing the mosquitos from transmitting the virus.
In order to accomplish this, the researchers injected Wolbachia bacteria into the mosquitoes that can prevent them from transmitting the dengue virus. The results from the study were published in two papers in the journal Nature. In their experiment, the chief researcher O’Neill and his colleagues injected the bacteria into 2,500 embryos of the mosquitoes that can spread dengue fever. After the mosquitos hatched, they were fed blood meals infected with the dengue virus. According to the research, none of the mosquitos became infected with the virus.
In this particular species of mosquito, when a male infected with dengue mates with an uninfected female, all of the resulting eggs die. When females infected with Wolbachia mate with males infected with dengue, their eggs hatch normally and all of the resulting offspring have Wolbachia in them. As a result, Wolbachia infected mosquitos become more common with each new generation of mosquitos.
There are two theories to explain why Wolbachia is able to prevent mosquitos from becoming infected with dengue fever. The first is that Wolbachia boosts the mosquito’s immune system and protects it from dengue virus. The second is that Wolbachia competes with the dengue virus for food inside the mosquito, making it harder for the dengue virus to replicate.