Global Change and invasive mosquitoes as infectious disease risks in Europe (GC-INVAMOFECT)

Invasive, non-indigenous species (NIS), are a threat to biodiversity and have repeatedly been recognized as one of the most important factors in the extinction or displacement of native species on a global scale. In addition, they cause significant economic and health damage which, in a recent report by the EU Commission, was estimated at 9.6 to 12.7 billion per year for Europe. Under globalization and climate change conditions it is assumed that the problems caused by NIS will increase and result in a growing displacement pressure on indigenous species. Above and beyond their ecological impact, invasive mosquitoes are a source of worldwide concern because of their utmost importance as vectors of a wide range of viral and parasitic pathogens affecting both humans and animals. Understanding current distribution and possible future expansion of invasive and native mosquito species is essential to guide coherent policy vector control in articulation with biodiversity conservation as well as environmental and human, animal health. Adaptation is defined as the ability to survive, function, and reproduce in an environment. There has been a widespread tendency to consider adaptation as genetic optimization, with the implication that natural selection is involved. In particular, insects display a remarkable range of adaptations to changing environments, due to specific genetic mechanisms in which the associated microbiota is now recognized to play a significant role. Following recent observations, different traits related to intrinsic characteristics and environmental conditions appear to be important factors contributing to the rapid spread of invasive mosquito species. GC-INVAMOFECT aims to investigate the contribution of the microbiota on the proven capabilities of mosquitoes to rapidly adapt to local environments, and thus promoting their successful invasiveness and increasing the risk for pathogens` transmission in colonized territories. To achieve answering the scientific questions raised above, four specific objectives were defined: (1) ecology of mosquito populations in natural environments, (2) microbiota as driving force for mosquito adaptation and invasion, (3) symbionts and mosquito vector competence of pathogens, and (4) modelling of present and future distributions. The Austrian group will work on all objectives and will be the leader of objective 3. This will explore the presence of multiple pathogens (e.g. viruses, helminths) by either retrieving information from Next-Generation Sequencing or screening of known or suspected pathogens in invasive mosquitoes. This will allow to establish a catalogue of pathogens and to enlighten possible interactions between pathogens or between pathogens and other microorganisms that could interfere with their transmission.

Alien, non-indigenous species have been recognized as one of the most important factors for the extinction or replacement of native species. In addition they cause significant economic and health damage. Invasive/alien mosquitoes are a source of worldwide concern because of their utmost importance as vectors of a wide range of viral and parasitic pathogens affecting both humans and animals. Understanding current distribution and possible future expansion of invasive and native mosquito species but also Mosquito Borne Diseases (MBDs) is essential to guide coherent policy vector control in articulation with biodiversity conservation as well as environmental, human and animal health. GC-INVAMOFECT is an ERA-NET BioDiversa2 project of following institutions: CNRS, University of Lyon FRANCE (Coordinator), IRD, Université de Montpellier FRANCE; Goethe University, Frankfurt am Main GERMANY and the University of Veterinary Medicine, Vienna, - AUSTRIA. The main focus was set on the occurrence, distribution and ecology of alien but also native mosquito species and MBDs. In Austria, more than 30,000 adult female mosquitoes were collected in the three easternmost provinces (Vienna, Lower Austria and Burgenland) including areas where Ae. albopictus had been detected for the first time. No populations of Asian tiger mosquitoes (vector of Dengue and other viruses) were detected in Eastern Austria. On the other hand the Asian bush mosquito (Ae. japonicus) established populations in Eastern Austria. Overall more than 30 mosquito species were observed in this study. Moreover barcoding and genotyping (e.g. house mosquitoes) and vector competence studies were performed. Moreover mosquitoes were screened for the presence of various MBDs including flaviviruses and filarioid helminths.