Alternaria Mold Info

Alternaria alternata

Exposure to Alternaria mold species can cause asthma, respiratory and skin infections. Alternaria alternata is the most common culprit. Alternaria morphology and elimination.

Where Does Alternaria Mold Occur?

Moldy Grapes on the Vine Poster

Alternaria fungus is a plant mold that occurs mainly in soil and on the leaves and fruit of many common plants.

It enters our homes on the skins of fruits and vegetables. The spores are easily spread on the wind so it also blows in through open windows. They then settle on various surfaces where they will multiply if left undisturbed.

Alternaria mold is black and velvety. It is caused by a plethora of Alternaria species, Alternaria alternata ,a.k.a. Alternaria tenuis, being chief among them.

Alternaria Morphology

The spores grow quickly and mature in 5 days. The fungus is flat and fuzzy due to its production of short, aerial hyphae. The colony may be gray, brown or black in color.

Alternaria Allergy

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Exposure to the spores has been suspected of causing hay fever in sensitive people but this has not been proven. What has been proven is the relationship between exposure to Alternaria alternata and the development of asthma symptoms.

Asthma is not the only consequence of exposure.

Various Alternaria spp can cause respiratory infections. Especially in people whose immune systems are suppressed such as AIDS patients or people who have had bone marrow transplants.

Alternaria fungus can also cause skin and systemic infections but this is uncommon.

Locating Alternaria in the home

The spores can live on many types of materials. It would be impossible to completely eradicate it from your home.

If you have asthma, keep your windows closed as much as possible between summer and fall when the outdoor spore counts are highest.

I was diagnosed with asthma more than 30 years ago. My doctor advised me to stay under filtered air in the summer months. When I fail to follow this advice, my symptoms worsen. When I follow it, I find it much easier to manage the disease.

Here in Florida where central air conditioning is the norm, this is easy to do. I just run the a/c during these seasons as the heat here is oppressive then anyway.

If you live in a cold climate, it might be more practical for you to invest in a good air filtering machine and run that instead.

If you do not have central air conditioning in your home, you will benefit from installing a window unit in your bedroom during the summer.

Alternaria mold grows most quickly in the presence of excess moisture. Alternaria and water damage go hand in hand.

Monitor the humidity in your home and use a dehumidifier if necessary. Do not allow pipes to leak. Run a fan in the bath after you shower to pull the excess moisture out before it can contribute to mold growth.

Water damaged building materials should be replaced but not as a DIY project. Hire someone else to do the work. Do not risk increasing your exposure.

If you do decide to remove some water damaged wood from your home, wear heavy gloves. Should Alternaria mold spores on a splinter become lodged in your skin, a nasty infection could develop.

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