Individual Sensitivities
When trying to determine how long a person can safely live in a moldy house, it is first important to determine the individual sensitivities of the individuals involved. In general, a person can live in a mold-infested house for several years although some people may experience severe discomfort. For example, if you suffer from asthma or mold allergies, you may have frequent asthma attacks or painful allergy symptoms, such as dark rashes, severe itching, sneezing and general discomfort. If you have a strong immune system and no mold sensitivities, you may notice no symptoms whatsoever.
Quality of Life
Since prolonged exposure to mold will likely not kill you, you must then consider your quality of life. Health sensitivities may cause you more discomfort and a much greater frequency of illness than you would experience in a non-moldy environment. Even if you have no specific allergies or respiratory problems, the microbial compounds from the mold may cause you to feel dizzy and disoriented, and the spores themselves may produce lung inflammation, such as hypersensitivity pneumonitis.
Children and the Elderly
While an adult with a healthy immune system may only suffer minor allergic reactions, this may not be the case for others. Anyone with a weaker immune system, such as an elderly adult, an infant or child or someone with an immune-deficiency disease, may suffer severe health repercussions. Someone with a severely compromised immune system, such as an AIDS patient, may experience infections that can ultimately lead to death. There is no way to determine how long such a person can survive in a moldy environment due to the many variables involved with each person, but for one's own safety, any immune-compromised person should leave a mold-infested environment immediately.
Types of Mold
The type of mold also plays a role in terms of how long a person can remain in the environment. For example, an allergenic strain, such as Cladosporium, may only upset allergy sufferers, but a toxic strain, like Stachybotrys or Aspergillus, may ultimately lead to some cancers, according to the Centers for Disease Control and Prevention. Only a mold expert can determine the type of mold in your home by examining it under a microscope; but if you have a toxic strain, you should remove the problem immediately.