Mildew can grow anywhere there is a nice, warm temperature, humidity and shade. It can be easily removed by with bleach solution. Mix one part bleach with 3 parts water.
Most of the times, cleaned spots will need a little painting. You can buy some special additives that prevent mildew from growing. Latex and alkyd paints are excellent because they allow the film to transpire reducing moisture problems. Keeping surfaces clean will keep your house mildew free.
Mildew can grow on any surface, even on fabrics. If cloths are affected by mildew they will have a certain musty smell. But this also happens to old cloths, even if they are not affected bu mildew. You should take them out in the air and sun light. Let them take some air and then you can wash them and also fully dry them.
Mildew can also be present in your kitchen. To avoid using chemicals near your cooking spot, use some backing soda and white vinegar to get rid of mildew.
Always be careful on what cleaners you are using. Sometimes these may be too abrasive for certain surfaces. Always read the information on the cleaners.
A nice way to clean mildew is with a handheld steamer. This will remove not only the mildew, but also any grease, stains from your walls, furniture, etc.