Italy invaded by cold-loving alien mosquito

Rome: Italy sees arrival of Aedes koreicus, a species of mosquito unafraid of the cold. The warmer months in Italy are associated with sun, sea and – for many people – mosquitoes.

Depending on how mild the temperatures are, the mosquito season in Italy generally lasts from spring until late autumn.

Not for much longer, according to a recent study by the University of Milan, published in Parasites & Vectors.

The study reveals a hardy “alien species” of mosquito that “tolerates low temperatures and prefers mountain regions” has made its home in the plains and foothills of Italy’s northern Lombardy region.

The Aedes koreicus, native to east Asia, was first detected in the northeast of Italy in 2011 and is now spreading towards the southwest of the country.

In the summer of 2020 researchers from the University of Milan carried out studies on new invasive mosquitoes in Lombardy, with a particular focus on the provinces of Bergamo and Brescia.

Of the approximately 6,000 mosquito larvae collected, they discovered that about 50 individuals belonged to Aedes koreicus.

This confirmed the spread of the species in the north of Italy, according to the researchers who said it also “raised concerns about its possible role as a vector of diseases in the Alpine area.”

The accidental introduction by man of alien species of animals and plants, outside their territory of origin, is a phenomenon on the rise thanks to changes in climate and the movement of goods and people.

Examples in Italy include the tiger mosquito (Aedes albopictus), originally from Asia and now widespread throughout Europe, and the pine tortoise scale insect (Toumeyella parvicornis) originally from North America and spreading rapidly along Italy’s Mediterranean coast.

“The Korean mosquito is endemic in Japan, northern China, South Korea and some areas of Russia. It was first reported in Italy in 2011 in the province of Belluno, at altitudes and climatic conditions unsuitable for the survival of most mosquito species”, researcher co-ordinator Prof. Sara Epis told state broadcaster RAI.

“Since then the reports in northern Italy have increased” – said Epis – “We emphasise that this mosquito, unlike the known “sisters” of the Aedes genus, such as the tiger mosquito, tolerates low temperatures very well, so much so that it has already colonised a large hilly-mountainous area of Veneto and Trentino.”

Paolo Gabrielli, a researcher in same the biosciences department as Epis, says: “Its presence in the foothills of the province of Bergamo leads us to think that the international airport of Orio al Serio could be a possible route of introduction.”

However he says the pest could also have been introduced to Bergamo “from other infested areas of Italy or Switzerland”, stating that further genetic studies are required.

“Apparently, the Korean mosquito is spreading from the original infested area to southern and western Italy” – Gabrielli told RAI – “probably in relation to the intense transport of goods and the availability of suitable habitats in other areas.”

Researchers conclude that their report “further emphasises the urgent need for coordinated efforts for the monitoring of invasive mosquitoes in Italy, to prevent the spread of vectors of emerging pathogens.”