ITM scientists find tiger mosquito eggs in Belgium

Last summer, scientists from the Institute of Tropical Medicine (ITM) in Antwerp discovered eggs from the tiger mosquito in a motorway service area near Aische-en-Refail in Namur. The exotic tiger mosquito or Aedes albopictus continues to spread in Europe and currently reaches Belgium via motorways from France and Germany. Researchers at ITM monitor risk sites where this species and other exotic blood-feeding mosquitoes are most likely to enter our country.

The tiger mosquito is a small insect that not only has a painful bite but can also carry diseases such as Zika, dengue and chikungunya. The species originally came from Southeast Asia but has spread to Europe and America due to the international transport of goods, global warming and its ability to adapt quickly. The species no longer confined to southern regions but making its way north. Colonies have already been found in central France and in Germany and the tiger mosquito is now arriving in Belgium not only through air traffic, but also via the highway from neighbouring countries.

"We examined four motorway service areas this summer and found tiger mosquito eggs in one car park. It is important that we monitor these new import sites carefully. Detecting the mosquitoes will be much more difficult in our country if they travel by car via German and French motorways to densely populated cities and municipalities," explains Dr Isra Deblauwe.

The tiger mosquito was also spotted on Dutch motorways near the Belgian border this summer. ITM researchers checked two additional car parks near to the Dutch border, but they found no tiger mosquitoes.

"Although the tiger mosquito is only spotted sporadically and has not yet settled here, the sightings are increasing in different locations. ITM started a large-scale exotic mosquito monitoring project in 2017 and has found tiger mosquitoes in Belgium every year since 2018. There is a real chance that the species will eventually be able to survive here. The timely mapping of these locations enables effective control and helps defer their establishment in our country as long as possible. Even if the mosquitoes are able to settle here, careful surveillance of these populations is a must to assess the risk of disease transmission," explains Dr Wim Van Bortel.

The MEMO project, short for 'Monitoring exotic mosquitoes in Belgium', is a three-year project (2017 - 2020), financed by the Flemish, Walloon and Brussels governments and the Federal Public Service Health, Food Chain Safety and Environment in the context of the National Environment and Health action plan (NEHAP). ITM carries out the project in collaboration with the Royal Belgian Institute of Natural Sciences (RBINS), and Barcoding Facility of Organisms and Tissues of Policy Concern (BopCo). With support from Avia-GIS, the VECMAP information system is used to integrate field and laboratory data. Flemish, Walloon and Brussels authorities are immediately informed each time tiger mosquitoes are detected so that control measures can be initiated quickly.

ITM has been carrying out surveillance of exotic mosquitoes at various locations in Belgium for many years. The Institute has been expanding these activities since July 2017 and doubled the number of locations investigated by the MEMO project. As a result of the years of monitoring, ITM researchers have built up a unique expertise and dataset, which accurately maps the first introductions of exotic mosquitoes in our country. This topic will be the subject of the documentary series Besmet shown on Canvas tonight at 9.20 pm.