In order to eliminate mosquitoes, human beings really use any means.A piece of news about Sun Yat-sen University using nuclear technology to kill mosquitoes rushed into hot searches, and related papers have also been published on Nature. Nuclear technology… kill mosquitoes? Isn’t it too cruel? Even more ruthlessly, Sun Yat-sen University also established a Nuclear Technology (Insect Sterility) Collaboration Center in June with the International Atomic Energy Agency. The two sides will cooperate on the use of nuclear technology to control infectious diseases transmitted by mosquitoes.
Visit:
Alibaba Cloud “88 Gangbang Festival”: free access to business plans, communication copywriting, and smart accounting tools
But don’t worry, it certainly doesn’t mean to use nuclear bombs to hit mosquitoes.
The nuclear technology here is to infertile mosquitoes through nuclear radiation. This method is called SIT (Sterile Insect Techniques)
The traditional method has always been to release the sterilized male mosquitoes so that they can snatch their wives from the fertile normal mosquitoes in the wild.
Female mosquitoes and sterile male mosquitoes cannot produce offspring after mating, and the number of this mosquito population is gradually reduced.
But! There is a problem here.
Nuclear radiation is not a joke. Male mosquitoes who have been exposed to radiation will not survive for a few days, and their mating competitiveness will decrease.
Radiated male mosquito: I want to grab my wife, but I can’t grab them.
Therefore, this method has not been successfully applied on a large scale.
How did Sun Yat-sen University succeed?
Sun Yat-sen University’s idea is very clever, combining SIT with IIT, another method of killing mosquitoes.
Let’s take a look specifically below.
Nuclear radiation + bacterial infection double insurance to kill mosquitoes
In addition to nuclear technology, there is also a method to sterilize male mosquitoes called IIT, Incompatible Insect Technique.
To put it simply, the male mosquitoes are infected with a bacterium called Wolbachia. The eggs produced by the infected male mosquitoes and female mosquitoes cannot develop after mating.
But! Yes, But is here again.
If female mosquitoes and male mosquitoes are infected with the same strain, their offspring can still develop.
This is because this bacteria is also ruthless.
In order to ensure the reproduction of its own population, Wolbachia has even evolved a mechanism that can manipulate the reproduction process of mosquitoes.
Wolbachia cannot be passed to the next generation of small mosquitoes through mosquito sperm, only through eggs.
So when the infected mosquito’s sperm are combined with the uninfected egg, Wolbachia has a way to make the first cell division of the small mosquito embryo fail.
If the egg is also infected, then there is nothing wrong with it. Let the infected mosquitoes develop successfully and continue to spread bacteria.
This method of IIT has only been successful in a few small-scale trials.
Because scientists want to cultivate infected mosquito pupae, it is difficult to accurately pick out every female mosquito when the number is large.
If an infected female mosquito is accidentally released, the entire mosquito population will be replaced with an infected mosquito over time, and subsequent reproduction will not be affected.
Two papers by Sun Yat-Sen University in 2015 and 2016 proposed the combination of SIT for nuclear radiation and IIT for bacterial infection.
The key point is that the researchers found that the radiation dose required to sterilize female mosquitoes is lower than that required to sterilize male mosquitoes, so low that it does not affect the reproductive competitiveness of male mosquitoes.
The specific plan is to cultivate a large number of mosquito pupae infected with Wolbachia, because the male pupae are generally smaller than the female pupae, and when they grow to a certain extent, the male and female pupae can be separated.
Low-dose nuclear radiation is applied to the pupae of male mosquitoes to ensure that they are sterilized even if the pupae of female mosquitoes are mixed in it.
Finally, the male mosquitoes infected with the bacteria and the sterilized female mosquitoes are released together to ensure that the method is successful in practical applications.
Guangzhou produces 5 million sterilized mosquitoes per day
Guangzhou is the city with the highest transmission rate of dengue fever in China because there are too many mosquitoes.
From 2015 to 2016, the Ministry of Agriculture approved the Sun Yat-Sen University team to conduct open-air release tests on Shazai Island in Nansha District of Guangzhou City and Dadaosha Island in Panyu District.
Through continuous release of sterilized mosquitoes for 2-3 years, the number of wild mosquito species is reduced by 83% to 94% each year on average, and no mosquitoes can be detected for up to 6 weeks, and the local mosquito population is basically eliminated.
In the beginning, a large number of mosquitoes were released into residential areas, and few local residents agreed.
After the experiment started, the effect was remarkable, and the number of people bites by mosquitoes in both places was greatly reduced.
Once again, more than 50% of residents expressed their support for this work.
Sun Yat-sen University is serious about killing mosquitoes.
According to the Guangdong Radio and Television Station, the “mosquito factory” in Guangzhou can breed 5 million sterile male mosquitoes every day.
Paper address:
https://www.nature.com/articles/s41586-019-1407-9
Reference link:
[1]
https://www.woidmo.org/vector-borne-diseases/sterile-insect-technique-mosquito-birth-control/
.