Isolation of antifungal-resistant <i>Candida</i> from the blowholes of captive dolphins

Abstract

In this study, we isolated eight strains of Candida albicans from the blowhole air cultures of eight dolphins (one Pacific white-sided dolphin and seven bottlenose dolphins) housed at the Enoshima Aquarium. The minimum inhibitory concentrations of antifungals for these isolates were determined by conducting E-test and broth microdilution assays using the CLSI M27-A3 protocol antifungal susceptibility testing method. Only one of the eight dolphins from which Candida had been isolated had been treated with amphotericin B (AMB), and four had been treated with itraconazole (ITZ).All isolates were identified as Candida albicans, and all were resistant to both ITZ and voriconazole, though the isolates exhibited susceptibility to AMB and micafungin.Based on our findings, we suspect that the frequency of occurrence of azole-resistant Candida species is increasing in captive dolphins as well as in their aquarium environments.

Candida spp. in Cetaceans: Neglected Emerging Challenges in Marine Ecosystems

“…In a recent study by Shirakata et al (2022) in an aquarium in Enoshima, Japan, eight C. albicans strains were isolated from the expired breath of 8 out of 12 dolphins (one Pacific white-sided dolphin and seven bottlenose dolphins) [ 62 ]. Remarkably, all isolates were resistant to fluconazole, itraconazole, and voriconazole but exhibited susceptibility to amphotericin B and micafungin.…”

“…Only one had a history of previous treatment with amphotericin B combined with itraconazole, and three colonized dolphins had been treated with itraconazole. However, a history of previous azole therapy was observed in four individuals who were colonized by azole-resistant C. albicans [ 62 ].…”