Epidemiology of endemic mycoses in Asia

Abstract

Endemic mycoses are caused by dimorphic fungi with geographical restriction in distribution. In Asia, histoplasmosis, talaromycosis (penicilliosis), and sporotrichosis are prevalent. Sporadic autochthonous cases of blastomycosis have been reported from India. Occasionally, coccidioidomycosis and paracoccidioidomycosis have been reported as imported disease. Recently, a new dimorphic fungus Emergomyces pasteuriana (taxonomy is not clear) has been isolated from few patients in India and is difficult to distinguish from Blastomyces dermatitidis morphologically. The epidemiology of histoplasmosis and talaromycosis is not clear. Contrary claims have been made regarding distribution of histoplasmosis. Similarly, source of Talaromyces marneffei in the nature is not known. Both the diseases have become important after AIDS epidemic. With anti-retroviral therapy, the prevalence of both diseases has come down. Histoplasmosis in immunocompetent hosts may present as mucosal ulcer and adrenal tumour. Among Sporothrix species, S. globosa is prevalent in Asia. Sporotrichosis is widely distributed in Asian countries especially China, India, and Japan. Several outbreaks have been reported in China from contaminated hay and cornstalk. More studies are required in Asian countries to know the exact epidemiology of endemic mycoses in this region.