Bacterial spores and sporocidal agents

Abstract

Bacterial spores are highly resistant to a wide array of chemical and physical agents, due to their specialised chemical and physical structure. Clostridium difficile spores are of considerable importance from an infection control perspective, since this organism is the most common cause of nosocomial diarrhoea. Few chemical biocides are actively sporocidal, and many of the disinfectants in use in hospitals are capable only of sporostasis. Examples include phenols, cresols, chlorhexidine, quaternary ammonium compounds and sub-lethal concentrations of chlorine-releasing agents and gluteraldehyde. Sporocidal agents include gluteraldehyde, sodium hypochlorite, iodine/iodophors, hydrogen peroxide and peracetic acid. Assessment or comparison of sporocidal agents should incorporate procedures for the recovery and revival of injured spores, to prevent overestimation of efficacy.