Recent work by a research group at Macquarie University in Australia have highlighted some starting findings regarding hospital bed sheets

Previous work by this research group has shown that dry surface biofilm is present on up to 93% of hospital surfaces, with over half of these biofilms containing multiple drug resistant organisms. One such surface that may harbour biofilm are the patient mattresses. this is exacerbated by the fact that patients continually shed microoragnisms into their immediate environment. Researchers found that pathogenic bacteria grown in a biofilm could be transferred through cotton sheets at rates of 100-1000 cells up to 20 consecutive times. This could potentially aid the spread of pathogens in a hospital setting, highlighting the importance of mattress cleaning and disinfection 

Only one product has been approved by the US EPA as being effective against healthcare associated biofilms, Medentech’s Klorkleen 2