Figure 2. Exposure of C. difficile PCR-ribotype 012, 017 and 027 strains to disinfectants.

Percentage survival after 30 minute exposure to A) Actichlor® at 5000 ppm, 1500 ppm, 1000 ppm and 500 ppm. B) Haztab® at 5000 ppm, 1500 ppm, 1000 ppm and 500 ppm. C) Perasafe® at 2%, 1.62%, 1% and 0.81%. D) Virkon® at 2%, 1.5%, 1% and 0.5%. E) Biocleanse® at 20%, 10%, 5% and 2.5%. F) Newgenn® at 0.8%, 0.4%, 0.2% and 0.1%. G) Proceine 40® at 6%, 0.6% and 0.06%. H) Steri 7® at 100%, 80%, 40% and 20%. I) Hibiscrub® at 50%. The survival was calculated as a percentage of the heat resistant spore counts from unchallenged cultures. Data consists of three biological and two technical replicates from separate cultures. <indicates survival was below the limit of detection of the assay (25 CFU/ml). Statistical analysis using linear regression (r²) and an interaction test (Chi²) was performed using the statistical program Stata 12. Bracket ∧ indicate a significant difference in concentration independent of PCR-ribotype (p<0.01), Bracket * indicates a significant difference between PCR-ribotypes independent of concentration (p<0.01) and Bracket ∧* indicates a significant difference between PCR-ribotypes in a concentration dependent manor (p<0.01).