Molds are micro plant organisms: fungi that during growth produce small spores (smaller than pollen) that are dispersed in the air and, if inhaled, cause an allergic reaction.

Although sporulation occurs mainly in summer and autumn, allergic manifestations can occur throughout the year: this is due to the fact that molds can be encountered both inside and outside the houses.

In Italy the most common and allergenic molds are Alternaria, which grows on decaying fruit and vegetables as well as in humid environments, Cladosporium, another vegetable mold, Aspergillus, which commonly proliferates on starchy foods such as potatoes and cereals and Penicillium which we find above all on citrus fruits, garlic, apples and pears. Aspergillus and Penicillium are the most common molds in indoor environments. The optimal conditions for their development are given by a temperature between 18 ° and 40 ° C and a humidity between 75% and 95%.

Some spores have such a shape that they can easily penetrate deep into the respiratory tract, reaching the bronchi and pulmonary alveoli. The inhalation of Alternaria spores, for example, represents a cause of bronchial asthma, precisely by virtue of its very small size.


The best treatment for any allergy is to take adequate measures to avoid exposure to the allergen. However, molds are very common and it is almost impossible to completely prevent any contact. If possible

  • Avoid environments such as greenhouses, antique shops, cellars, stables and saunas.
  • Periodically clean the air conditioning filters.
  • Avoid walking in the woods and contact with wood piles or piles of leaves.
  • Indoor plants are not the main source of mold in the home, but it is prudent to limit the number.
  • In the bathroom and in the kitchen, use a suction fan or change the air immediately after taking a shower and after cooking.
  • Clean the refrigerator very frequently, taking care to remove any spoiled food immediately.
  • Air dry clothing immediately after washing. If you are allergic to Alternaria it is best to dry your clothes inside the house with the help of a dehumidifier.
  • For household cleaning use products that kill molds.
  • Wallpaper is a very favorable place for mold growth.
  • In the bedroom, implement the same rules suggested for environmental prophylaxis against the dust mite.