Abstract: The present invention provides a filtration medium comprising an ultrafiltration membrane and a monomer surface coating thereon of an acrylic or methacrylic acid monomer having alcohol functional groups, wherein the filtration medium after having been fully dried is characterized by having a titer reduction of at least about 10.sup.3 with respect to PP7 bacteriophage and a critical wetting surface tension of at least about 70 mN/m. The filtration medium preferably further comprises a fibrous nonwoven web embedded in the membrane. The present invention also provides a method of filtering a fluid through the present inventive filtration medium, as well as a method of preparing such a filtration medium.