The bright future of darkness—the rising power of black fungi: black yeasts, microcolonial fungi, and their relatives

Abstract

Black fungi are no longer viewed as neglected, rare, or exotic fungi—in fact, we now realize that they are all around us on a daily basis. In the past, we just have been looking at the wrong places, with inadequate detection tools, or with inappropriate isolation methods. In a way, the seemingly ubiquitous presence of black fungi is disturbing, reflecting one of the bright/ dark contrasts of our research field: while scientists in the black yeast area all recognize the frustration of projects being rejected because of supposed societal insignificance, the general public tends to be afraid of these dangerous and omnipresent fungi. This fear dates back to 1934 when K. Kano described Hormiscium dermatitidis from a disfiguring facial infection in Japan. Since that time, many more severely mutilating and eventually fatal infections in apparently healthy people have been reported; the present issue of Mycopathologia contains another horrid example. Later, it was realized that these infections are related to diseases like chromoblastomycosis and primary cerebritis, which are already known for more than a century. Thus, severe black yeast diseases occurred long before organ transplantation was even invented, and in times when immune disorders like leukemia inevitably were rapidly followed by death. Black fungi belong to nature’s repertoire of primary pathogens, it seems, because they are able to kill healthy and immunocompetent individuals. But how come that we are still alive; why has humanity not been eradicated by these potent and widely dispersed organisms? The answer must be that pathogenicity in black fungi is mostly coincidental,