One large study found 31 different types Candida species in clinical samples, but just five of those account for more than 90% of all infections in humans: C. albicans, C. glabrata, C. kreusi, C. parapsilosis, and C. tropicalis. These species have become increasingly common in recent years, some of which are associated with severe illness (C. tropicalis) or antibiotic resistance (C. parapsilosis).