Virulence Attributes in Aspergillus fumigatus

Abstract

Aspergillus fumigatus is one of the most important opportunistic fungal pathogens. It causes various types of infections in humans, from skin, lung, and allergic infections to invasive infections. However, these stand out because their mortality rate can reach up to 95%. A. fumigatus is a ubiquitous fungus and, therefore, humans are in constant contact with it without major risk, except when there is a predisposing factor on the host, that allows the fungus to penetrate and invade the tissues. It is fascinating how this fungus manages to go from harmless to pathogenic as, in addition to the predisposing factors of the human, multiple attributes of the fungus intervene that favor its growth and survival in the host. Among these virulence attributes are thermotolerance, the ability to evade the immune response, some components of the cell wall, the production of secondary metabolites, compliance with nutritional requirements, and the production of melanin, among others. Furthermore, some of these virulence attributes are interrelated, making understanding the pathogenesis of aspergillosis more complex. This chapter presents a review of some virulence attributes that are known, to date, in A. fumigatus.