It’s just the fitted sheet. The encasement I have is actually not a plastic wrap but a zippered tight weave synthetic fabric (polyester). https://a.co/d/3ut09

It’s just the fitted sheet. The encasement I have is actually not a plastic wrap but a zippered tight weave synthetic fabric (polyester). https://a.co/d/3ut09wO https://a.co/d/3ut09wO It’s suppose to prevent bedbugs and others from setting up shop inside the mattress but the surface is fair game. The idea being it’s easier to clean the surface than the insides. I have had the encasement for years. No problems with humidity but I also live in a less humid area (41-45% rh all year round). So a dust mite vaccuum still makes sense. Also interesting fact: dust mites themselves are harmless to humans. It’s their fecal matter (after digesting our dead skin) that are allergens.