Efficacy of common antiseptics against mycobacteria

SETTING AND OBJECTIVE: Antiseptics are frequently used to prevent mycobacte rial infection; however, the reported activities of a number of antiseptics against mycobacteria are not always consistent, The aim of this study was to determine those antiseptics that are useful against mycobacteria. DESIGN: Evaluation of antiseptic activity against mycobacteria in vitro. RESULTS: The effects of different antiseptics on mycobacteria (Mycobacteriu m avium, M. kansasii and M. tuberculosis) were examined. At concentrations of 0.05%, povidone-iodine (PVP-I) killed 99% or more of all strains tested within 15 seconds, while 0.5% chlorhexidine gluconate and 0.1% benzalkonium chloride showed no bactericidal activity against mycobacteria. M. kansasii and M. tuberculosis were killed after exposure to cresol for 60 seconds at concentrations of 1.0%, but M. avium was unaffected even after 60 seconds. While M. kansasii and M. tuberculosis were killed by treatment with 2.0% g lutaraldehyde for 5 minutes, M. avium was highly resistant to this agent. CONCLUSION: PVP-I seems to be a useful antiseptic against mycobacteria. The measured activity of antiseptics should be interpreted carefully, due to t he potential for interference by artifacts.