Key Facts:
- Aspergillus is a type of mold commonly found indoors and out, in soil, dust, plant material and even food. It is harmless to healthy people but can cause illness in those with lung disease, a specific immune sensitivity to aspergillus, or weakened immune systems.
- Aspergillosis cannot be spread from person to person.
- Though most people with a healthy immune system can fight off the infection, anyone with a weakened immune system or underlying lung condition could be at risk of developing aspergillosis.
- There are three main forms – allergic, chronic and invasive.
Who Is at Risk?
If you are in good health, your body should be able to defend itself against inhaled Aspergillus spores before they can cause an infection. However, anyone with a weakened immune system or an underlying health condition could be at risk. Certain factors that make you particularly susceptible are:
- Low white blood cell count. This includes anyone undergoing chemotherapy, who is living with HIV/AIDS, who has had an organ transplant or patients with leukemia.
- Long-term lung disease, such as COPD or tuberculosis, that may cause cavities in lung tissue where the infection can take hold.
- Having asthma or cystic fibrosis, that can make you more susceptible to having an immune sensitivity to the Aspergillus mold.
- Long term use of corticosteroids or other immune-suppressing medications.
What Causes it?
Aspergillus, the mold that causes the disease, is found everywhere, indoors and outdoors. For people with a healthy immune system, it rarely causes a problem because their body can destroy the spores. That is why people with weakened immune systems are at the highest risk—they are unable to fight off the infection before the fungus invades the lungs and other parts of the body.
How Aspergillosis Affects the Body
Aspergillosis severity varies depending on what form you have. There are three main categories—allergic, chronic and invasive.
Allergic bronchopulmonary aspergillosis occurs when people develop an immune sensitivity to aspergillus after inhaling the mold. While not common, this disease tends to be seen more often in people with asthma or cystic fibrosis.
Chronic pulmonary aspergillosis occurs in people who already have a chronic lung condition, such as TB, emphysema, COPD or advanced sarcoidosis. The fungus starts to grow in existing cavities in the lung caused by the underlying lung disease. Over time, the aspergillosis may cause these cavities to enlarge and increase in number. This process can also damage or alter the blood vessels in the lungs, which can result in bleeding.
Invasive aspergillosis is the most uncommon but most severe form of the disease because it affects all parts of the body. This is most common in someone with a weakened immune system, such as patients undergoing chemotherapy or people who have had an organ transplant. In these patients, the infection spreads rapidly from the lungs to the brain, heart, kidneys or skin, and can be life-threatening.
Reviewed and approved by the American Lung Association Scientific and Medical Editorial Review Panel.
Page last updated: January 25, 2021
