Breathing mold into the lungs, especially for a long period of time, may trigger allergic reactions and worsen symptoms of asthma and other respiratory conditions.

Some types of mold may cause aspergillosis, which is a group of lung infections that occur when a person inhales fungi from the Aspergillus genus.

People who live in damp environments are at a higher risk of mold-related illnesses, even when there is no visible mold. These environments also tend to attract other organisms that may affect a person’s health, including cockroaches, dust mites, viruses, and bacteria.

Removing mold and moisture from the home can help mitigate these risks. In some cases, mold may require professional mitigation and removal.

This article discusses types of mold that can affect a person’s lungs. It also explores the symptoms, diagnosis, treatment, and prevention of mold in the lungs.

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Many types of mold can affect the lungs. Additionally, the environments that allow mold to grow (those that are damp and moist) may be harmful to the lungs, even in the absence of mold.

One of the risks to lung health comes from members of the Aspergillus genus of fungi. The spores of the fungi can enter a person’s lungs and cause an infection that doctors call aspergillosis. Some forms of this fungi that may affect the lungs include:

  • A. terreus
  • A. flavus
  • A. fumigatus
  • A. niger

Aspergillus molds can cause lung and sinus infections that range from mild to severe. Immunocompromised individuals and people with underlying lung diseases are more vulnerable to severe infections.

Outside of Aspergillus molds, any type of mold may irritate the lungs and respiratory system when a person experiences chronic exposure to the organism or if they are allergic to it. Some potential effects include:

Exposure to Aspergillus molds may cause a wide range of respiratory symptoms, including:

  • coughing
  • sneezing
  • worsening allergy symptoms
  • exacerbations of COPD and asthma

Aspergillosis can cause sudden, intense symptoms, such as:

When Aspergillus molds enter the sinuses, they may cause:

These symptoms are more common in people with conditions that weaken the immune system. People who are severely immunocompromised, however, may not develop a fever.

Some people may also develop chronic pulmonary aspergillosis, which is a long-term lung infection. The most common symptom of this is a cough. The infection may also spread to the blood vessels, causing a person to cough up blood, or throughout the body, causing symptoms such as:

When a person has symptoms of aspergillosis or experiences any other respiratory symptoms, it is important for them to tell their doctor if they think they have experienced exposure to mold.

A healthcare professional may be able to determine whether a person is allergic to mold or whether mold is worsening the symptoms of any respiratory conditions a person has.

Additionally, a doctor may order imaging tests, such as chest X-rays or CT scans, if they suspect someone has aspergillosis. Imaging of the lungs may show a nodule on the lungs where the mold has grown. According to 2012 research, a doctor can conclusively diagnose aspergillosis with a lung biopsy.

They may also take samples of a person’s phlegm and blood or take cultures from a person’s airways.

Treating mold-related allergic reactions and illness exacerbations requires removing mold and dampness from a person’s home. In some cases, a person might need additional treatment for underlying illnesses. For example, a person with asthma may have to begin using an inhaler until asthma attacks subside.

Aspergillosis requires prompt medical treatment. In most cases, a doctor should initiate treatment before they make a conclusive diagnosis if there is strong evidence of the infection.

Treatment typically involves a person taking an antifungal medication, such as voriconazole. However, the type of medication a doctor prescribes may depend on the type of Aspergillus mold causing the condition because some species are resistant to certain antifungal medications.

Antibiotics will not treat aspergillosis because it is not a bacterial infection.

If a person is very sick, they may also need supportive care in a hospital setting.

Preventing aspergillosis and other mold-related illnesses requires reducing dampness and removing mold. If there is mold in a person’s home, it may make a musty odor. It may also be visible.

To reduce dampness, a person may try the following:

  • Use a dehumidifier in humid areas of the home, aiming to keep humidity below 50%.
  • Fix any leaks in the home.
  • Increase air movement by using a fan or opening windows.
  • Run fans in the kitchen and bathroom to reduce moisture.
  • Clean damp areas where mold may grow.
  • Remove any standing water in the home.
  • Clean or remove any moldy objects, such as chairs or furniture, from the home. Warm water and detergent can typically remove mold.
  • Hire a professional mold removal company if the mold covers a large area of the home.

Mold is an allergen and an irritant that can cause breathing problems in some people. It may also worsen underlying respiratory diseases.

Certain types of mold may also cause harmful infections. People who experience any potential symptoms of aspergillosis or other symptoms following mold exposure should seek medical care.

A person can take steps to help prevent dampness and mold in their home, such as fixing leaks, increasing air circulation, and using a dehumidifier.