So some Chinese researchers managed to eradicate the entire tiger mosquito population in two islands located in southern China, Shazai and Dadaosha, in the delta of the Guangzhou city.
In these parts mosquitoes are scary because in some cases they can be carriers of diseases that are potentially lethal for humans such as yellow fever, Zika virus and encephalitis. It is for this reason that scientists have experimented with a new method to extinguish the insect from inhabited areas, where citizens are more exposed to the risk of being stung.
The research, conducted by Professor Xi Zhiyong of the Joint Vector Control Center for Tropical Diseases of Sun Yat Sen University with the support of the Guangzhou Center for Disease Control and Prevention, has yielded excellent results, at least judging from the first experiments carried out.
The new method aims at reversing the evolutionary balance of mosquitoes, preventing males and females from reproducing. To do this, the researchers placed a mosquito breeding plant on the island, in which a large sample of insects was subjected to sterilisation. Male sterilisation took place thanks to the artificial induction of three infections from as many different species of the Wolbachia parasite; the female one after the release of gamma radiation.
Once sterilised, the modified mosquitoes were released in bulk. At this point the insects, endowed with low fertility, are paired with the healthy specimens they have encountered in the environment, causing the infertility of the new generations. Repeating the process for two years, the mosquito population was almost completely zeroed.
The breeding plant in Guangzhou province is capable of producing 10 million male mosquitoes modified per week. Although there are no contraindications for humans, there are those who have emphasised how such a method can have a serious ecological impact; mosquito larvae, in fact, are an important source of food for fish, while this insect is one of the favourite dishes of many birds.