Some antifungal drugs, such as those working against Aspergillus fumigatus and Candida, are becoming less effective due to an increase in resistance. As a result, it is becoming more difficult to treat people with these fungal infections. The substances in antifungal medicines, mainly azoles, are often used in agriculture as well. Fungi that have become resistant to these substances in agriculture can also be resistant to similar medicines for humans (cross-resistance). That is why RIVM recommends taking the possibility of cross-resistance into consideration when allowing antifungals onto the market for use in agriculture.
RIVM also recommends limiting the use of antifungals in agriculture where possible and using certain substances only in medicines for humans. Additional research is needed to determine how resistant fungi in the environment may reach patients in the hospital.
Becoming ill from fungal infections
Fungi can make people ill. Most fungal infections are innocent, but some can be life-threatening. People with weakened immune systems, such as cancer and AIDS patients, or carriers of transplant organs, are particularly at risk. Cross-resistance to azoles has already been demonstrated in the fungus Aspergillus fumigatus. This makes an infection with this fungus more difficult to treat in humans.
Indications for resistant types of Candida
According to RIVM, there are also indications that several Candida types may be or become cross-resistant. For example, some resistant Candida types have been found in the environment. There is also a chance that new antifungals currently in development will be used in both agriculture and to treat people, which could lead to cross-resistance.
RIVM conducted this research on behalf of the Ministry of Agriculture, Fisheries, Food Security and Nature.