Dengue-Blocking Mosquitos Released in Brazil

clinical researchFor those that live in tropical regions,there is an everyday concern about contracting a mosquito-borne illness called dengue fever. Typical symptoms of dengue fever are non-lethal and include fever, headache, joint pain and rashes. The disease can also however manifest into hemorrhagic fever and dengue shock syndrome which in some cases can be deadly. Dengue is most severe in countries like Brazil, Australia, Vietnam, Indonesia and the Philippines. With 50-528 million infected every year, scientists are working hard to develop a vaccination for this disease, however the process has been slow. The first steps towards a large-scale cure began just this month, when scientists at the Rio de Janeiro Fiocruz Institute bred a batch of mosquitos infected with dengue-blocking bacteria. Clinical research training has helped scientists ensure that these mosquitos will effectively counteract the dengue illness carried by mosquitos, and eventually spread to also block the infection in the mosquito’s offspring.

The Science

For this research experiment, mosquitos have been infected with Wolbachia, a bacteria which suppresses dengue fever. Properties of Wolbachia make it so that a female infected with the bacteria cannot mate with an unaffected male—which means killing off species infected with dengue in favour of those with Wolbachia. Clinical researcher schools and laboratories have been researching vaccines since the 1970s when the first severe cases of this disease were reported. So far, there has not been a vaccine approved by WHO, and releasing these infected mosquitos is the first large-scale trial to eradicate the disease.

Ethical Considerations

As a disease that threatens 40% of the world’s population, there have been attempts and proposals in the past to simply commit genocide on the mosquito population. Mosquitos are not only carriers of dengue, but also many other deadly diseases like West Nile, malaria and Yellow fever. Some scientists have proposed killing the mosquito population through genetic modification, which would cause offspring born by infected mosquitos to have an abnormally short lifespan—too short to bite humans and infect them with dengue. By releasing dengue-blocking mosquitos, scientists are attempting the more ethical manner to control the disease, with the least impact on the ecosystem.

There are however vaccines in the works, in fact the first batch is expected to be released in 2015. When a proper vaccination has been developed, scientists may work with pharmaceutical regulatory affairs schools to get the counter drug onto the market to help the millions of people affected by the illness yearly. However even with a vaccine, the infections of dengue will not stop and will only be cured, which is why it is so important that scientists are performing this dengue-blocking mosquito study. Scientists expect to see a reduction of dengue fever in Brazil in approximately two years. The purpose of this study is to get information which could back a longer project of five to ten years with the intention to completely eradicate the disease.

Here are the mosquitos officially being released into the wild: