Researchers target disease-spreading mosquito found in Algarve
Asian tiger mosquito (Photo: Pixabay)

Researchers target disease-spreading mosquito found in Algarve

Pilot-project involves releasing sterile males into the wild to reduce their population

A “unique” pilot-project in Portugal designed to eradicate the Asian tiger mosquito (Aedes albopictus) – which has been found in the Algarve and can spread diseases such as dengue, zika and chikungunya – is being carried out by the Ricardo Jorge Institute and the Algarve Health Authority (ARS Algarve).

Researchers are using the sterile insect technique (SIT), which involves sterilising male specimens using radiation and releasing them back into the wild so that when they mate with females, no offspring will be born.

The sterilised mosquitoes used in the project were brought in from a laboratory in Italy and were kept at the Laura Ayres Regional Public Health Laboratory at Parque das Cidades, near the Algarve Stadium, until their release.

For three weeks, they were released in 40 spots across a 40-hectare area in Gambelas (Faro).

“This is an invasive mosquito which is linked to diseases such as dengue, zika and chikungunya, which is why it is a species that is a cause of concern for public health,” the project’s coordinator Nélia Guerreiro told TSF radio.

Researchers have been following the spread of this species since it was first detected in the municipality of Loulé in 2018.

While there have been no reports of these diseases being spread by the mosquitoes in the Algarve, the researcher adds says that this could change if their population increases.

“We are monitoring because we need to have a log, understand how they behave and during which periods they are most active,” Guerreiro explained.

Meanwhile, another researcher Hugo Osório has stressed that the sterile male mosquitoes which have been released pose no danger to humans.

“It is essential for people to understand that these sterile mosquitoes which have been released do not bite,” he said.

The released mosquitoes have been sprayed with florescent powder in order to help researchers identify them. The team has been returning to Gambelas to catch the mosquitoes and see if they have been surviving.

“The fact that they are still here means they are, which is good. And if we catch them far away from this area, it will mean that they have the capacity to disperse,” Guerreiro told the radio station.

But will female mosquitoes want to mate with males covered in fluorescent powder?

The researchers reacted with laughs when questioned by TSF, but Hugo Osório provided an  answer: “If the percentage of sterile eggs increases, it is possible that the females do not find them odd. It will mean that the sterile males are competitive when faced with wild males.”

By Michael Bruxo

michael.bruxo@portugalresident.com