Aspergillosis is the name of a group of conditions caused by a mould called Aspergillus. This family of moulds usually affects the respiratory system (windpipe, sinuses and lungs), but can spread to anywhere in the body in those that are immunocompromised.

Aspergillus is a group of moulds found all over the world and is common in the home. Only a few of these moulds can cause illness in humans and animals. Most people are naturally immune and do not develop disease caused by Aspergillus. However, when disease does occur, it takes several forms.

The types of diseases caused by Aspergillus are varied, ranging from an allergy-type illness to life-threatening generalised infections. Diseases caused by Aspergillus are called aspergillosis. The severity of aspergillosis is determined by various factors, but one of the most important is the state of the immune system of the person.