At the tip of an iceberg: citizen science and active surveillance collaborating to broaden the known distribution of Aedes japonicus in Spain

Abstract

Background Active surveillance aimed at the early detection of invasive mosquito species is usually focused on seaports and airports as points of entry, and along road networks as dispersion paths. In a number of cases, however, the first detections of colonizing populations are made by citizens, either because the species has already moved beyond the implemented active surveillance sites or because there is no surveillance in place. This was the case of the first detection in 2018 of the Asian bush mosquito, Aedes japonicus, in Asturias (northern Spain) by the citizen science platform Mosquito Alert. Methods The collaboration between Mosquito Alert, the Ministry of Health, local authorities and academic researchers resulted in a multi-source surveillance combining active field sampling with broader temporal and spatial citizen-sourced data, resulting in a more flexible and efficient surveillance strategy. Results Between 2018 and 2020, the joint efforts of administrative bodies, academic teams and citizen-sourced data led to the discovery of this species in northern regions of Spain such as Cantabria and the Basque Country. This raised the estimated area of occurrence of Ae. japonicus from < 900 km2 in 2018 to > 7000 km2 in 2020. Conclusions This population cluster is geographically isolated from any other population in Europe, which raises questions about its origin, path of introduction and dispersal means, while also highlighting the need to enhance surveillance systems by closely combining crowd-sourced surveillance with public health and mosquito control agencies’ efforts, from local to continental scales. This multi-actor approach for surveillance (either passive and active) shows high potential efficiency in the surveillance of other invasive mosquito species, and specifically the major vector Aedes aegypti which is already present in some parts of Europe. Graphical abstract

First Nationwide Monitoring Program for the Detection of Potentially Invasive Mosquito Species in Austria

“…Thus, to establish an Austrian-wide early warning system for the detection of AIM species, the number of sampling sites should be increased in the future. In addition, a combination of a nationwide monitoring project together with a citizen science project such as “Mosquito Alert” (pan-European) or “Mückenatlas” (Germany), which provide simple tools for citizens to report (alien) mosquito species, would increase the chances for an early detection of AIM species [ 65 , 66 , 67 ].…”

Laboratory Evaluation of Flight Capacities ofAedes japonicus(Diptera: Culicidae) Using a Flight Mill Device

“…japonicus . Based on records made by Eritja et al (2021) , Ae. japonicus distribution expanded around 3,000 km 2 per year during the 2018–2020 period in Spain.…”

Integrating Global Citizen Science Platforms to Enable Next-Generation Surveillance of Invasive and Vector Mosquitoes

“…Mosquito Alert is a citizen science system that has been initiated and managed by public research institutions, with the goal of bringing the general public together with academics, public health authorities, and other stakeholders to study and control the spread of disease-spreading mosquitoes worldwide [ 14 , 16 , 41 , 42 ]. The project was launched in June 2014 with an initial focus on Ae.…”

“…albopictus [ 14 ], as well as the first detection of Ae. japonicus in Spain [ 41 , 42 ] and Ae. vittatus in Galicia [ 43 ], and this list continues to grow.…”