A harmonised dataset of adult Culex pipiens mosquitoes from 17 administrative Italian regions, 2008–2022

Culex pipiens s.l. is the primary vector of West Nile Virus in Italy. Despite the availability of abundant long-term surveillance data on adult Cx. pipiens observations in Italy, historical records are often fragmented across regional repositories with heterogeneous formats and metadata. This work introduces a comprehensive, harmonised dataset of adult Cx. pipiens observations collected across 17 Italian administrative regions from 2008 to 2022. The dataset, compiled from official surveillance programmes conducted by the Experimental Zooprophylactic Institutes network and collaborating institutions, encompasses 58,888 raw observational records of adult Cx. pipiens, corresponding to 37,070 unique trap deployments. To ensure cross-regional comparability, these overlapping local observations were harmonised and spatio-temporally aggregated onto a 9 × 9 km reference grid compatible with ERA5-Land climate reanalysis, providing weekly median abundances. The data were stratified by trap type and mosquito sex, resulting in 50,759 analysis-ready records. Following rigorous quality-control procedures for taxonomic reliability and spatio-temporal consistency, this dataset constitutes an essential resource for spatio-temporal modelling of vector phenology, epidemiological forecasting, and advancing integrated One Health preparedness.