Genetically closely related skin bacteria that have developed resistance to several different antibiotics and that can cause intractable care-related infections are found and seem to be spreading within and between hospitals in Sweden. This is established by Micael Widerstr÷m in the doctoral dissertation he is defending at Umeň University in Sweden. Coagulase-negative staphylococci (CNS) are bacteria that belong to the protective bacterial flora on the skin and seldom cause infections in healthy individuals. However, CNS, and especially Staphylococcus epidermidis, are a common cause of care-related infections, in particular infections following various types of prosthetic surgery. These infections are often difficult to treat, as certain strains of S. epidermidis have become resistant to most antibiotics (multi-resistant), and has a capacity to fasten on and form a so-called biofilm around catheters and inserted prostheses.