Help....We lease a home where the air unit is completely overtaken by mold and mildew!! Should we move??

We recently found out that our central air unit in the home that we lease is completely overtaken by mold and mildew. They will have to replace the whole unit. We have lived in this home for five months without knowledge of this problem. Is this hazardous to our health to live here even after the unit has been replaced? We have been breathing this dirty air for five months. Is this is in our walls, carpet, and furniture? What should we do? Any help will be appreciated.