We had gotten a vacation home in June of 2009 and about 3 weeks later I started getting bug bites. I researched what to do and did all the suggestions on your website and no more problems. Unfortunately, I hated the new mattress. So 10 months later we took off the bed bug mattress covers (King size) to replace with new mattress (Cal King size) and a few nights later I got another bite. I think it was inside the mattress cover on the old mattress and dropped out when we took it off the old mattress and the bug took a few days to crawl back up to me. I couldn't put the mattress cover back on the new mattress because it was the wrong size. So I am back to the website to order the Cal King mattress cover and box spring covers and I will be doing an aggressive bug termination again like I did last year. I wasn't sure how well the mattress covers worked until now 10 months later. The mattress cover is comfortable to sleep on. We didn't notice it made any difference, but I put a regular mattress pad on top of it.