The widespread use of azole fungicides (azoles), notably in some agricultural and horticultural operations, raises the possibility of Aspergillus fungus acquiring resistance to critical antifungal treatments. This noteworthy result is emphasized in a paper published by the five EU health and environment agencies, with cooperation from the European Commission's Joint Research
Azole medications are essential for treating aspergillosis, a serious infection caused by the Aspergillus fungus. However, these fungi are growing increasingly resistant to azole treatments, rendering treatment ineffective.
Azole substances are widely used in plant protection products (‘pesticides’) to control fungal diseases in agriculture and horticulture, as veterinary medicines to treat fungal infections in animals, as biocides in wood preservatives, as industrial chemicals (e.g. intermediates and dyes), and in cosmetics (e.g. as anti-dandruff agents). The joint report highlights that their broad use outside human medicine, particularly in agriculture, contributes to the risk of Aspergillus becoming azole-resistant. Exposure to certain environments where azole fungicides are used or present, such as agricultural and horticultural waste and freshly cut wood, can potentially increase the risk of infection with azole-resistant Aspergillus spp. Data collected from EU/EEA countries (2010–2021) and included in the report detail the use of azole fungicides across Europe. Plant protection products account for most of the reported sales across all sectors.
Tackling azole resistance in Aspergillus requires cross-sectoral collaboration. The One Health approach brought together EU experts from human and veterinary medicine, agriculture and environmental sciences to review existing evidence, identify factors that promote azole resistance, and propose measures to prevent and control it. Recognising the interconnected nature of this challenge, the Agencies’ experts recommended the following actions:
- Adding new specific requirements to the approval and authorisation processes for azole fungicides;
- Supporting research into and development of new fungicides with innovative mechanisms of action that do not lead to resistance to antifungal medicines used in human treatments;
- Following good agricultural and horticultural practices, properly storing organic waste, managing waste effectively, and using and disposing azole-treated products responsibly;
- Implementing effective waste management for wood treated with azole-based biocides;
- Collecting more data on the uses of azole-based fungicides and of azole-based antifungals;
- Further developing specific technical guidance and risk assessment methodologies to support regulatory decisions on the approval of azole substances and to mitigate the risk of azole resistance in Aspergillus;
- Conducting further research to address existing uncertainties.
The report reinforces the value of a One Health approach in addressing complex health threats like antifungal resistance. By continuing cross-disciplinary collaboration, we can strengthen surveillance, advance research, and implement effective measures to safeguard public health, animal health, and the environment.
