Aspergillosis is an infectious, non-contagious fungal disease caused by species within the ubiquitous opportunistic saprophytic genus Aspergillus, in particular Aspergillus fumigatus. In poultry, infection by A. fumigatus may induce significant economic losses particularly in turkey production. A. fumigatus develops and sporulates easily in poor quality bedding or contaminated feedstuffs in indoor farm environments. Inadequate ventilation and dusty conditions increase the risk of bird exposure to aerosolised spores. The respiratory tract is the primary site for A. fumigatus colonisation, leading to severe respiratory distress and associated granulomatous airsacculitis and pneumonia. It infects the respiratory system of many kinds of birds, leading to a range of disease manifestations from acute to chronic infections. Acute cases are seen in young birds following inhalation of spores, causing high morbidity and mortality. The chronic form affects older birds and appears more sporadically. Treatments for infected poultry are non-existent; therefore, prevention is the only way to protect poultry. The mechanism of host-pathogen interaction, early diagnostic methods and antifungal treatment schedules need to be further studied in order to control this disease.

Aspergillus fumigatus has become a leading cause of fungal morbidity and mortality, especially in immunocompromised patients. This fungus is able to grow as a multicellular community and produce a hydrophobic extracellular matrix (ECM), mainly composed of galactomannan and α-1,3 glucans, to protect itself from host defenses and antimicrobial drugs. This matrix envelops the fungus hyphae, binding them into a contiguous sheath on the colony surface, forming a biofilm and increasing the fungal resistance to adverse environmental factors. Adherence to host cells and resistance to physical removal play a key role in fungal colonization and invasion of the host and in a wide range of infections. Here we show that, by using atomic force spectroscopy, it is possible to exploit the peculiar hydrophobicity of the biofilm components (i.e., cell walls, ECM) to detect the biofilm spread, its growth, and lysis on rough surfaces. By means of this approach, we demonstrate that alginate lyase, an enzyme known to reduce negatively charged alginate levels in microbial biofilms, reduces the biofilm adhesion forces suggesting a loss of ECM from the biofilm, which could be used to enhance pharmacological treatments.

Twenty-six adult cystic fibrosis patients were studied to compare nasal disease with their laboratory correlates including skin testing, immunoglobulin and Aspergillus fumigatus precipitin levels, saccharin testing and sputum cultures. Six patients were asymptomatic and all of these had negative skin tests, normal IgE levels and negative Aspergillus fumigatus precipitins. Thirteen patients had rhinitis, 12 had positive skin-testing for common allergens, 10 elevated IgE levels and nine positive Aspergillus fumigatus precipitins. Seven patients had polyps, all had normal IgE levels and negative Aspergillus fumigatus precipitins, six had positive skin testing for common allergens. There also appeared to be a relationship between Pseudomonas spp. colonization and positive skin testing.

Most necrotizing (malignant) external otitis (NEO) occurs in diabetic patients and is commonly caused by Pseudomonas aeruginosa. We report an acquired immunodeficiency syndrome (AIDS) patient with NEO caused by Aspergillus fumigatus in which computed tomography (CT) showed destructive petrous bone involvement and magnetic resonance imaging (MRI) of the ear discovered extensive soft tissue and facial nerve involvement. Dedicated MRI studies of the ear in this type of pathology provide new insights relating to nerve dysfunction, that cannot be obtained with CT.