For example, the mold type Penicillium grows best at 34 degrees Fahrenheit, which is the typical temperature inside of a refrigerator. In contrast, Aspergillus is mold that prefers warmer temperatures of 98 degrees Fahrenheit, which is the normal temperature inside the human body.
The optimum temperature range for development of Aspergillus is 62.6–107.6°F, minimum temperature for growth is 51.8–55.4°C.
Aspergillus fumigatus—What Makes the Species a Ubiquitous Human Fungal Pathogen?
Goldilocks Gold – 98.6*F – Optimal Physical Environment
Inhaled conidia readily germinate at the mammalian body temperature since 37°C is the optimum temperature for both germination and growth. Conidia shed the hydrophobin layer and swell in 4 h to germinate into short hyphae by 6–8 h at 37°C in vitro as well as in immunocompromised mammalian tissue .–> Sub-Telomere Directed Gene Expression during Initiation of Invasive Aspergillosis.
At body temperature, 37ºC, the relative humidity of the lungs ranges from 30% to 70%, whereas recommended humidity ranges from 30% and 50% . The relative humidity tends to be higher in the summer . High humidity can cause problems since high humidity lends itself to optimal microbial growth . Humidity is lowest during winter months . Low humidity can be problematic as dry air makes mucous membranes dry, making them more susceptible to infection .