Be assured that vinyl wall covering does not attract mildew to walls. Mildew is a product of environmental factors. Normal room temperature range provides an excellent climatic environment for mildew growth. Food sources include any organic material such as wood, drywall, paper, cloth etc. The third element, and trigger mechanism, is moisture.
T here is always a pattern to mildew growth.
Sometime the pattern is easy to identify, such as the mildew growth is on the same wall in every room. At other times you need to look for the pattern, such as in only one section of the building or every other wall, etc. Once the pattern is identified you look for the cause of humidity. It could be a water pipe break inside a wall, air-conditioning condensation seeping into walls, or rainwater seeping from windows due to poor seals. In every case we found the cause for the humidity and were able to rectify the problem.