Disclosed are polyolefin or polyester fibers, films and molded parts that have excellent durable antimicrobial activity. The polyolefins and polyesters have incorporated therein one or more silver antimicrobial additives and one or more wettability additives. The silver antimicrobials are for example silver supported on a zeolite, silver supported on a glass, elemental silver, micro or nano scaled elemental silver, elemental silver dispersed in silocone oil, silver chloride, silver nitrate, silver sulfate, silver phosphate, silver zirconate or silver apatite. The wettability additives are for instance ethoxylated alcohols CH3CH2(CH2CH2)aCH2CH2(OCH2CH2)bOH where a is 6 to 25 and b is 1 to 100 or are alkyl metal sulfonates of formula RSO3M, where M is Na, K or Li and R is straight or branched chain alkyl of 6 to 32 carbon atoms or is straight or branched chain alkenyl of 6 to 32 carbon atoms. The present compositions retain antimicrobial activity after repeated insults.