First report of the invasive mosquito species Aedes koreicus in the Swiss-Italian border region.

Tobias Suter,Pie Müller,Lukas Engeler,Begoña Feijoó Fariña,Mauro Tonolla,Eleonora Flacio

doi:10.1186/s13071-015-1010-3

Abstract

BackgroundIn 2012 and 2013, an entomological survey of Aedes albopictus, the Asian tiger mosquito, was carried out in the border region of southern Switzerland and northern Italy, using ovitraps. In July 2013, besides A. albopictus already known to the region several unusual eggs were recovered.FindingsA total of 548 seemingly different eggs were found within three communities: Chiasso (Switzerland), and Como and Brunate (Italy). Proteomic diagnostics based on matrix-assisted laser desorption/ionization mass-spectrometry (MALDI-TOF MS) and morphological identification of one reared adult revealed the presence of at least 18 A. (Finlaya) koreicus (Edwards, 1917) specimens. A. koreicus is a species native to Southeast Asia and is competent to transmit Japanese encephalitis and potentially other arboviruses, as well as the dog heartworm Dirofilaria immitis. While new to Switzerland, this invasive species has previously been reported from Belgium, north-eastern Italy and European Russia.ConclusionsThis is the first report of the introduction of this exotic mosquito species into Switzerland and Lombardy, Italy, suggesting the range of A. koreicus is expanding in Central Europe. As A. koreicus is competent to vector pathogens its establishment imposes a risk to public and veterinary health. From a technical point of view, the presence of A. koreicus alongside A. albopictus requires careful analysis and reliable diagnostics. As a diagnostic tool the use of the recently developed MALDI-TOF MS approach has proofed to be a very useful approach, particularly since hatching rates of A. koreicus seem to be low, making identification by classic morphology difficult, if not impossible.

Highlights

In 2012 and 2013, an entomological survey of Aedes albopictus, the Asian tiger mosquito, was carried out in the border region of southern Switzerland and northern Italy, using ovitraps
This is the first report of the introduction of this exotic mosquito species into Switzerland and Lombardy, Italy, suggesting the range of A. koreicus is expanding in Central Europe
As A. koreicus is competent to vector pathogens its establishment imposes a risk to public and veterinary health

Summary

Introduction

In 2012 and 2013, an entomological survey of Aedes albopictus, the Asian tiger mosquito, was carried out in the border region of southern Switzerland and northern Italy, using ovitraps. After the introduction and establishment of the Asian tiger mosquito, Aedes albopictus (Skuse), in the Swiss Canton of Ticino in 2003, an entomological surveillance and control programme was instigated by the canton’s mosquito working group, Gruppo cantonale di Lavoro Zanzare (GLZ) [1]. GLZ uses ovitraps for the surveillance of A. albopictus as a basis for interventions in urbanised areas where the mosquito has become endemic [2]. In 2012 and 2013, as part of a research project the mosquito survey was expanded across the Swiss-Italian border, including the Mendrisiotto district (Switzerland) and the northern part of the Lombardy (Italy). Seventy grid cells were randomly selected in both countries using the “sample()”

Results

Discussion

Conclusion