Bactericidal Activity of Ready-To-Use Alcohol-Based Commercial Wipes According to EN 16615 Carrier Standard.

BACKGROUND: The effectiveness of ready-to-use disinfectant wipes was previously assessed in standardized suspension tests, which were inadequate because they ignored that the wipes are rubbed against a surface. Thus, we assessed the effectiveness of commercially available disinfectant wipes impregnated with an alcoholic solution according to the 16615 standard, which includes a test with mechanical action. METHODS: According to the EN 16615 standard, under clean conditions, four squares (5cm x 5 cm), placed next to one another, were marked on a test surface. Enterococcus hirae, Pseudomonas aeruginosa, and Staphylococcus aureus were inoculated on the leftmost square, and a wipe impregnated with an alcoholic solution was placed to the left of that square. Then, the wipe was pressed with a 2.5 kg weight and moved to the right and back to the left. After contact times of 1, 5, 10, or 15 minutes, we measured the reduction in bacterial load. RESULTS: Alcohol-based ready-to-use commercial wipes did not show sufficient bactericidal activity at the contact times of 1, 5, 10 and 15 minutes. Wipes containing propan-1-ol and a mixture of propan-1-ol and propan-2-ol were active against Pseudomonas aeruginosa at the contact times of 1 minute and 15 minutes. None of the examined wipes were active against Enterococcushirae or Staphylococcusaureus. CONCLUSION: Bactericidal parameters of ready-to-use disinfectant wipes should be determined in surface tests, in addition to suspension tests, because suspension tests do not simulate the conditions under which disinfectant wipes are used in practice.

[Whole cell protein profiling characterization of Corynebacterium diphtheriae clinical isolates collected from various infections].

INTRODUCTION: Corynebacterium diphtheriae can cause various infections such as diphtheria, wound infections, septic arthritis, bacteraemia and endocarditis. Different virulence properties of the isolates might be related to different virulence factors expressed by the isolates. The objective of this study was to explore whether whole cell protein profiling might be useful in prediction of pathogenic properties of C. diphtheriae isolates. METHODS: C. disphtheriae isolates collected from diphtheria, invasive and local infections and from asymptomatic carriers in Poland, France, New Caledonia and Canada in 1950-2014 were investigated using whole cell protein profile analysis. RESULTS: All the examined isolates were divided into two clades: A and B with similarity about 47%, but clade B was represented by only one isolate. The clade A was divided in two subclades A.I NS .II with similarity 53,2% and then into four groups: A.Ia, A.Ib, A.Ic and A.Id. The comparative analysis did not distinguish clearly toxigenic and nontoxigenic isolates as well as invasive and noninvasive isolates. CONCLUSIONS: Whole cell protein profile analysis of C. diphtheria exhibits good concordance with other genotyping methods but this method is not able to distinguish clearly invasive from non-invasive isolates.