Antifungal drug development is hampered because of the close similarities between fungal and human cells compared with bacterial and human cells; the search for compounds that selectively inhibit fungi with minimal toxicity to the patient is laborious and requires substantial financial resources.

Despite this complication, several promising new agents, including entirely new classes of molecules, have entered clinical trials in the past decade. But even before they reach the market after years of development and clinical trials, fungicides with similar modes of action are developed by the agrochemical industry resulting in cross-resistance for critical priority pathogens such as A fumigatus.

We are back where we started in terms of the future sustainability of treating azole-resistant A fumigatus with currently available antifungals. As large proportions of essential crops are affected by fungi, antifungal protection is required for food security. The question is, how do we balance food security with the ability to treat current and future resistant fungal pathogens?