Biological weed control to relieve millions of allergy sufferers in Europe

BACKGROUND AND OBJECTIVES Invasive alien species (IAS) can substantially affect ecosystem services and human wellbeing. However, quantitative assessments of their impact on human health are rare and the benefits of implementing sustainable IAS management likely to be underestimated. MATERIAL AND METHODS In this study, we quantify the effects of the allergenic plant Ambrosia artemisiifolia on public health in Europe using pollen data and assess the potential impact of the accidentally introduced leaf beetle Ophraella communa on the number of patients and healthcare. RESULTS We find that, prior to the establishment of O. communa in 2013, some 13.5 (95% confidence interval (CI) 10.9-14.8) million persons suffered from Ambrosia induced allergies in Europe, causing economic costs of approximately Euro 9.0 (CI 7.3-9.9) billion annually. Field studies in Italy proved evidence that O. communa can reduce A. artemisiifolia pollen production by 82%. By modelling the number of generations of O. communa across its suitable habitat range in Europe, we project that biological control of A. artemisiifolia will, once the leaf beetle has colonized its environmental niche, reduce the number of patients to about 11.2 (CI 8.6-12.9) million (mean reduction 16.9 %) and the health costs to Euro 7.5 (CI 5.8-8.6) billion per year. CONCLUSIONS Our conservative calculations indicate that currently discussed economic costs of IAS underestimate the real costs and thus also the benefits from biological control