Copper salts of ion exchange materials provide copper ions at levels suitable for use as an anti-infective agent. The copper salts of ion exchange materials may be formed using ether and ester derivatives of cellulose, such as carboxymethyl cellulose (CMC), ethylcellulose (EC), methylcellulose (MC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose (HEMC), cellulose acetate, and cellulose triacetate. Wound dressings having copper salts of ion exchange materials incorporated therein are also provided, and may be used to reduce the incidence of infection in wounds. The wound dressings may also be used to prevent infections in long-term wounds, such as those formed at wound drain, catheter, and ostomy entry sites. Copper salts of ion exchange materials may be used to kill microorganisms, and may optionally be used with additional anti-infective agents.