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Effectiveness of disinfection with alcohol 70% (w/v) of contaminated surfaces not previously cleaned
Maurício Uchikawa Graziano1, Kazuko Uchikawa Graziano, Flávia Morais Gomes Pinto
1Escola de Enfermagem, Universidade de São Paulo, São Paulo, SP, Brazil. kugrazia@usp.br
Objective:
To evaluate the disinfectant effectiveness of alcohol 70% (w/v) using friction, without previous cleaning, on work surfaces, as a concurrent disinfecting procedure in Health Services.
Method:
An experimental, randomized and single-blinded laboratory study was undertaken. The samples were enamelled surfaces, intentionally contaminated with Serratia marcescens microorganisms ATCC 14756 106 CFU/mL with 10% of human saliva added, and were submitted to the procedure of disinfection WITHOUT previous cleaning. The results were compared to disinfection preceded by cleaning.
Results:
There was a reduction of six logarithms of the initial microbial population, equal in the groups WITH and WITHOUT previous cleaning (p=0.440) and a residual microbial load ≤ 102 CFU.
Conclusion:
The research demonstrated the acceptability of the practice evaluated, bringing an important response to the area of health, in particular to Nursing, which most undertakes procedures of concurrent cleaning /disinfecting of these work surfaces.
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