VectorNet: collaborative mapping of arthropod disease vectors in Europe and surrounding areas since 2010

Background: Arthropod vectors such as ticks, mosqui-toes, sandflies and biting midges are of public and vet-erinary health significance because of the pathogens they can transmit. Understanding their distributions a key means of assessing risk. VectorNet maps their distribution in the EU and surrounding areas. Aim: We aim to describe the methodology underlying VectorNet maps, encourage standardisation and eval-uate output. Methods: Vector distribution and surveillance activity data have been collected since 2010 from a combina-tion of literature searches, field-survey data by ento-mologist volunteers via a network facilitated for each participating country and expert validation. Data were collated by VectorNet members and extensively vali-dated during data entry and mapping processes. Results: As of 2021, the VectorNet archive consisted of ca 475,000 records relating to > 330 species. Maps for 42 species are routinely produced online at sub-national administrative unit resolution. On VectorNet maps, there are relatively few areas where surveil-lance has been recorded but there are no distribution data. Comparison with other continental databases, namely the Global Biodiversity Information Facility and VectorBase show that VectorNet has 5-10 times as many records overall, although three species are better represented in the other databases. In addi-tion, VectorNet maps show where species are absent. VectorNet's impact as assessed by citations (ca 60 per year) and web statistics (58,000 views) is substantial and its maps are widely used as reference material by professionals and the public. Conclusion: VectorNet maps are the pre-eminent source of rigorously validated arthropod vector maps for Europe and its surrounding areas.