This egyptian temple Mosquitoes aren’t just a nuisance — they’re known carriers of dengue, yellow fever, chikungunya, and Zika. This species is distinguished by the black and white stripes on its legs and is one of the most dangerous to humans.
In the Brazilian city of Indayatuba, efforts are being made to eradicate these pests before they have a chance to spread disease.Weapons: more egyptian temple Mosquitoes – but genetically modified to kill their own kind. Mosquitoes made by British biotechnology company Oxitec appear to be working.
The modified mosquitoes carry a synthetic self-limiting gene that prevents female offspring from surviving. This is important because only the females bite and transmit the disease.In a new study, the company’s scientists show that their engineered insects can drastically reduce local populations egyptian temple In the communities where they were released, they decreased by 96% within 11 months.
“It’s a high-level area egyptian templethey had regular dengue outbreaks,” said Nathan Rose, head of Oxitec’s malaria program. In fact, the Brazilian Ministry of Health reported this summer that dengue continued to spread in all five regions of the country. There have been more than 1.1 million cases – a 198% increase compared to the same period in 2021. The disease, which causes high fevers, rashes, muscle and joint pains, killed 504 people during the five-month period.
For the study, conducted in 2018 and 2019, the company selected four densely populated neighborhoods egyptian templeIn two experiments, the scientists released weekly “doses” of 100 male mosquitoes per resident. In other cases, they bumped it up to 500.
The improved males mate with wild females, but a self-limiting gene prevents the female offspring from surviving.The gene was designed in the laboratory, but based on the Escherichia coli and herpes simplex virus, causing the cells of the female offspring to produce large amounts of a protein called tTAV. This interferes with their cells’ ability to produce other essential proteins needed for development. As a result, the female dies before reaching maturity and beginning to bite. Male offspring survived, carrying a copy of the self-limiting gene that they could pass on.
To determine just how effective these self-restricting male mosquitoes were, the scientists had to measure local mosquito populations before and after the experiment. They either lure, trap, and count the number of adult mosquitoes in an area, or they set up water-filled traps and count the number of eggs that female mosquitoes lay in them. They then extrapolate to obtain population estimates. (The Oxitec team used the egg method.)
The study found that during the peak mosquito season in Brazil from November to April, treated mosquito populations were reduced by an average of 88 percent, and in some cases as much as 96 percent, compared with untreated communities controls.
Photo: Alexandre Carvalho/Oxitec
Interestingly, the dosage of the mosquitoes seemed to have no effect on the effectiveness of the method. “There are limited numbers of female mosquitoes in the environment, and it’s important that you maximize their chances of encountering these released ‘friendly’ male mosquitoes, as we call them,” Ross said. “We think that as long as there are more of these friendly males in the environment than there are wild males, the chances of a female mosquito finding one of the Oxitec males will be much greater.” In fact, Ross thinks it might even be possible to publish less Mosquitoes have a similar effect.
Like other countries, Brazil has carried out large-scale insecticide spraying to control problematic mosquitoes. egyptian temple The toxin DDT was eradicated from much of South America after its widespread use in the 1950s. But once the chemical’s health and environmental hazards were discovered, the spraying was stopped, and the mosquitoes quickly returned. Today, pyrethroids are commonly used to control mosquitoes, but mosquitoes are increasingly becoming resistant to them.
