Pathogens

Aspergillus fumigatus – Infection, Transmission & Diseases

Aspergillus fumigatus

Aspergillus fumigatus is a mold from the genus Aspergillus . It is considered a high health risk for people with an immune deficiency .

What is Aspergillus fumigatus?

The mold Aspergillus fumigatus comes from the genus Aspergillus (watering can mold). The Latin name “fumigatus” is due to the smoky green color of the fungus. It is caused by a pigment inside the spores.

Aspergillus fumigatus is a human pathogenic fungus . That means he in humansdiseasescan cause. It is used to synthesize mold toxins (mycotoxins) such as gliotoxin, fumagillin, fumitremorgins, verrucologists and sphingofungins.

Occurrence, Distribution & Properties

Aspergillus fumigatus is one of the most widespread life forms worldwide. It occurs all over the world from Antarctica to the Sahara in high or low abundance. It can be found, for example, on rotting plants, in the soil, on compost heaps, on nuts and grain, and on moldy food. Sometimes the Aspergillus spores (conidia) are also spread via air conditioning systems that are not properly maintained. Construction sites are also a conceivable source of mold infection, since there are large amounts of fungal spores in the construction dust.

Aspergillus fumigatus grows in heavily flocculent or deeply folded colonies. The smooth, short conidiophores reach a height of around 300 micrometers. Occasionally they can even be 500 microns. Their diameter is between 5 and 8 micrometers.

Another typical feature is their greenish color up to the vesicle. Opening at the stalks into vesicles 20-30 micrometers in diameter occurs. They show the same coloring as the conidiophores. Their fertility is usually only in the upper half. The conidia are spherical in shape and have an irregular surface. Their diameter varies between 2.5 and 3 micrometers.

The first stage of life of the Aspergillus fumigatus takes place as a conidia. The extremely small mold spores are extremely resistant to drying out, high temperatures and even disinfectants . If the spores have enough nutrients and water, they can germinate so that individual hyphae form. These hyphae branch out as they progress. This leads to the development of a so-called mycelium (hyphal network).

Individual conidiophores develop on the surface of the mycelium. The function of these heads is to produce more spores. Approximately 10,000 new fungal spores are formed per conidiophore. The spores are spread by the wind. Their reproduction process takes place asexually.

Aspergillus fumigatus is a saprophytic fungus. This means that it feeds on dead plant parts. With the help of its versatile metabolism, it is able to decompose many substances. In addition, it can withstand temperatures of up to 48 degrees Celsius.

The spores of Aspergillus fumigatus get into humans through the inhaled air. They are so small that they can penetrate into the human alveoli (air sacs in the lungs). Another possibility of transmission is skin or mucous membrane injuries.

The preferred contact places include compost, organic bins, potting soil and wallpaper. But accumulations of moisture in the apartment or in the basement can also promote the spread of Aspergillus fumigatus.

Diseases & Ailments

Serious damage to health is possible as a result of Aspergillus fumigatus. In the case of a mold infection in humans, doctors speak of aspergillosis . In most cases, this shows up in the lungs or the paranasal sinuses . However, sometimes areas such as the gastrointestinal region , the nervous system or the skin are also affected.

While the mold does not usually pose a threat to people with an intact immune system , people with a weakened immune system due to previous illnesses or taking immunosuppressive drugs are particularly at risk. In healthy people, the mold spores are successfully combated by the immune system, but in sick people they can settle in the lungs, paranasal sinuses or ear canal and trigger a fungal infection there.

In Germany alone, there are around 5,000 infections with Aspergillus fumigatus every year. About 90 percent of all aspergillosis are caused by this type of mold. The infection ends fatally in every second patient.

A major problem is that there are hardly any effective drugs available to combat aspergillosis. The research for an effective drug continues. The progress of research is hampered by the fact that the structure and metabolism of human cells and fungal cells are similar. Due to the dramatic course of the disease, doctors administer antimycotics , which have a broad spectrum of effects, even if there is a mere suspicion of aspergillosis.

There are different types of fungal infections caused by Aspergillus fumigatus. They depend on which organ is affected by the infestation. So there is, inter alia, the aspergilloma in the paranasal sinuses. It shows up in the context of sinus infections , so that the patients often do not even notice the fungal infection. In the worst case, the fungal spores spread to the brain .

Aspergilloma in the lungs often affects people who suffer from lung diseases such as bacterial pneumonia , tuberculosis or bronchial carcinoma . The fungal spores settle in cavities in the lungs that are caused by these diseases. In addition, severe allergic reactions are possible, which are noticeable through coughing and sputum .

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.