Dengue always threatens the health of Argentina. So far this year, 1,587 cases have been officially reported, with an increase more than double compared to the previous report from the Ministry of National Health.
Aedes aegypti is essential to prevent the spread of the virus, it must fight the mosquito that transmits it. For this reason, preventive measures are very important, to eliminate the breeding sites of these mosquitoes, which are containers with stagnant water, inside and outside the houses.
However, scientific research is progressing in the development of another method that can contribute to the next fight against this disease.
Specialists from the National Atomic Energy Commission are working on the application of the Sterile Insect Technique (SIT) on mosquitoes of the Aedes aegypti genus, carriers of dengue, zika and chikungunya, viruses that circulate widely during hot seasons in all countries. Latin American countries.
“The goal is to reduce the population of Aedes aegypti and in this way to reduce the probability of people being infected with dengue, Zika or chikungunya,” explained the biologist Marianela García Alba, researcher of the laboratory. We use a technique that has many advantages, because it is the same mosquito that controls itself. In this way we also reduce the use of insecticides, which are harmful to the environment and the people where they are applied. First of all, the probability of contracting these three viral diseases for which there is no vaccine should be reduced.
A sterile mosquito
Mariana Terrada, head of the agricultural applications department of the CEA, indicates that this sterile insect technique “is used to control agricultural pests. It is applied to control fruit flies. It already works in the field. Now we use it to control dengue. We have been working on this project since 2016.”
He explains “from the competition of these mosquitoes, which are born massively in the factory, the males (which do not bite) are separated from the females (which do bite), the males are sterilized with gamma rays and then sent into the field. And they compete with the wild males. They do not leave sterile mosquitoes offspring. “
Male mosquitoes are sterilized with gamma rays when they are mature in the pupal stage at the Irradiation Semi-Industrial Plant (PISI) of the Ezeiza Atomic Center.
“Irradiation must be done at a specific time. To do this, it is necessary to “synchronize” the breeding so that all people are in the necessary state at the time of irradiation. This depends a lot on the type of food and the temperature, aspects that we can control in the laboratory”, says García Alba.
release and control
Albanus says that the release was already made under the terms of the trial in Ezeiza. “Mosquitoes are born, called, marked with fluorescent powder, released and captured. This trial allowed us to know what is the flight capacity of these mosquitoes, and what survives in the field. . He tells us that he behaves sterile like wild males in the field.”
“If everything goes well, the pilot release could be done at the end of the year. First it was done in a small site, for example six blocks, and then there is a scale. After that it is monitored weekly,” says the researcher. .
He teaches that “the number of sterile mosquitoes depends on the area in which they are released.”
But he points out that to fight the disease, “it is still necessary for the whole society to exclude ticks and stop breeding mosquitoes. The method contributes more. It is not a magic technique.”
Dengue is a viral disease transmitted by the bite of the Aedes aegypti mosquito. A mosquito with the blood of a person infected with dengue virus, replicates into a mosquito and then, for 8 to 12 days, becomes infected, transmitting the virus to other people through its bite.
Symptoms usually appear 5-7 days after infection (but can be anywhere from 3-14 days). Common symptoms are fever (usually 3-5 days), severe headache, muscle and joint pain, pain behind the eyes, hunger, vomiting, and rash.
Chikungunya viral fever is also transmitted by the bite of an infected Aedes aegypti mosquito. Symptoms usually begin 3-7 days after being stung.
The most common is a sudden onset of fever greater than 38°, often with general pain. Other symptoms that appear are muscle aches, headaches, nausea, fatigue, and rash. Severe joint pain usually lasts a few days, but can persist for months, affecting full recovery and return to daily activities.