Transformation and standardization of the inactivation test method for virus suspension in biosafety laboratory / 中国比较医学杂志

Chemical disinfectants are generally used for virus inactivation and environment disinfection in biosafety laboratory, and the efficacy and evaluation of the disinfection are critical to ensure the laboratory biosafety.However, there is a current lack of applied standard to evaluate the virucidal efficacy of chemical disinfectants in our country.In this paper, a European Union standard“Method and Requirements of Virucidal Quantitative Suspension Test Method for Chemical Disinfectants Used in Human Medicine” was analyzed and a standard transformation scheme has been proposed.It is suggested that the model viruses should be increased from 3 to 6, including the surrogate viruses to substitute highly pathogenic viruses, and that the method to remove the residual chemical disinfectant and the calculation of 95%confidence interval should be incorporated into the standard.The suggestion will improve the scientific and operational standards related to disinfection and sterilization in biosafety laboratory in China.

Evaluation of A Chlorine Dioxide Disinfectant for Dental Unit Waterlines / 中华医院感染学杂志

OBJECTIVE To investigate the use of a chlorine dioxide-based dental unit waterline(DUWL) treatment to reduce the colonization and growth of heterotrophic bacteria.METHODS Twenty-two dental units with self-contained water systems were randomly selected.Three of the units and tap water served as controls.Twenty-three water samples were taken at baseline and once a week for five weeks.They were serially diluted,spread-plated in duplicate onto R2A agar plates and incubated at 37 ℃ for 7 days.RESULTS At baseline,the 3 control DUWLs had a median count of 8440 colony-forming units/milliliter(CFU/ml) and the 19 treated DUWLs had a median count of 9160 CFU/ml.By week 1,18 of the 19 treated DUWLs had counts of less than 200 CFU/ml,and by week 4,the median count for all of the treated DUWLs was 0 CFU/ml.The measurement at week 5 showed that the reduction to below 200 CFU/ml had been maintained.Scanning electron examination revealed a similar results,with biofilm accumulation more evident in the untreated control specimens.CONCLUSIONS Using a chlorine dioxide-based disinfectant in DUWLs can achieve the American Dental Association(ADA) goal of less than 200 CFU/ml of heterotrophic bacteria per milliliter of unfiltered output water.

Chemical Disinfectant Application:Problems and Countermeasures / 中华医院感染学杂志

OBJECTIVE To investigate the problems and countermeasures in the chemical disinfectants application.METHODS To analyze the existing problems in the chemical disinfectants application from 8 hospitals of different care levels at the same city and provide corresponding measures.RESULTS There were many problems in the use of chemical disinfectants,therefore the key points were enhencing the leadership and management standards,staff training,of corresponding knowledge and the correct methods,and strengthening the guidance,inspection and supervision by functional departments.CONCLUSIONS Medical personnel must properly use the chemical disinfectants to ensure the medical safety and prevent hospital infection effectively.