An Assessment of Alternative Therapeutic Options for the Treatment of Prolonged Zoonotic Fungal Infections in Companion Animals

Abstract

Zoonotic disease is an ongoing issue, becoming more prominent as more microbial species display antimicrobial resistance. The role of companion animals in society is also increasing as therapy dogs become the mainstay for many special needs persons. In order to ensure public health safety, it is essent ial to determine the extent of resistance amongst zoonotic pathogens and where possible to suggest novel treatment options to counteract such resistance. Fungal species are increasingly recognised as the causative agent in numerous incidents of canine morb idity. Therefore, the development of new, safe and effective chemotherapeutic agents is essential to prevent and control mycotic disease. Chronic incidents of cutaneous candidiasis as diagnosed in the cases used for this study are particularly high risk fo r zoonotic transmission. Studies described herein evaluate the resistance of these canine isolates of Candida species to common antifungal agents and identify levels of resistance using recognised in vitro methods. Results show high levels of resistance to amphotericin B, fluconazole and caspofungin for Candida albicans and Candida krusei isolates. This clinical resistance was more prominent in isolated species compared to control species. Novel compounds namely phendione and Roussin Black salts show promis ing antifungal activity with minimum inhibitory concentrations determined.