Mold spores are everywhere, and they are brought into the home by clothing, shoes, and gusts of air that carry them inside. There are always some mold spores in any home. The problem arises when that mold is allowed to make a home and procreate. A severe mold problem can cause decay in the home and can lead to unintended negative health consequences.
Mold will hide anywhere it is allowed, and it can sit dormant for a long time waiting for the right environment to grow. It may hide behind drywall, tile, flooring, or any number of surfaces. As long as the area remains dry, it is inactive and dormant. It will not cause health problems or decay. However, as soon as moisture is added to the area, you will have a big problem.
Once mold is exposed to favorable growing environments, it will start growing again, but it will be a while before you notice it. You may note a damp, musty smell. You may actually see it appearing on the outside of the wall or other surface. As soon as you detect it, efforts should be made to stop it from growing again. The hidden danger is that mold can grow for quite a while until it becomes detectable. By the time it is found, it can effect entire areas of the building.
If you suspect you have black mold, which is also named toxic black mold, you should hire professional mold removers to take care of it properly. Black mold and other molds can contain mycotoxins that can cause health problems. Most of these health problems involve respiratory issues. They are especially dangerous to those already suffering from respiratory conditions or those who are immunocompromised. In rare but concerning cases, black mold has been named as the cause of the death of multiple people.
Mold removal experts can test your walls by drilling small holes in them and testing the region behind the wall for mold. If mold is detected, the drywall, flooring, or other surface may have to be removed and disinfected. This is why you want to detect mold as soon as possible. It can be a huge project to properly remove a large amount of mold.
The biggest danger from mold that is hidden in walls yet inactive is that it can become reactivated if exposed to moisture. It is important to repair whatever problem allowed the spores to enter that region of the home and remedy it, so the risk of reactivation is low.