Three-year assessment of integrated vector management in Attica, Greece: results from surveillance and control activities

The West Nile virus vector Culex pipiens and invasive species Aedes albopictus are abundant in Attica, Greece, which deploys an integrated vector management program for targeted vector control. The objective of our study is to evaluate the effects of this program on mosquito vector populations. Using mosquito surveillance and intervention occurrence data, we assessed the effects of mosquito control interventions on vector populations using a two-stage interrupted time series (ITS) approach. First, we fitted ITS models to 16 weeks of data centered on the week of each unique species-specific intervention. Second, we pooled the estimated coefficients in a meta-regression model. Following vector control interventions at the targeted intervention sites, we observed an overall 34% reduction (RR 0.66; 95% CI 0.50-0.89) in Culex pipiens counts and a nonsignificant 5% increase (RR 1.05; 95% CI 0.81-1.35) in Aedes albopictus counts, compared to the pre-intervention period. These results support the implementation in reducing Culex pipiens populations in Attica as part of an integrated public health plan to mitigate West Nile virus risk. However, the limited impact on Ae. albopictus suggests the need for complementary strategies beyond conventional biocides. Overall, this study could serve a model for evaluating IVM programs in diverse settings.