Abstract: Objective To evaluate the characteristics and changes of microbial distribution on the surface before and after disinfection of different donor populations with the existing blood donor arm skin disinfection methodand to provide a basis for the development of appropriate disinfection methods or standards. Methods The skin surface specimens of 200 blood donors before and after disinfection were collected by contact dish sampling, cultured and purified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).Results The results of skin disinfection monitoring of 200 donors met the criteria; A total of 49 bacterial species were detected in the pre-disinfection samples, of which Gram-positive and Gram-negative bacteria accounted for 75.51% (37/49) and 24.49% (12/49), respectively, and 19 bacterial species were detected in the post-disinfection samples, of which Gram-positive and Gram-negative bacteria accounted for 84.21% (16/19) and 15.79% (3/19), respectively; the indoor group The residual rate of bacteria after disinfection was significantly lower than that of the outdoor group, P<0.05. The highest residual rates after disinfection in the indoor group were Acinetobacter baumannii, Acinetobacter loftii, Staphylococcus saprophyticus, Bacillus subtilis, Campylobacter and Propionibacterium spp. The highest residual rates after disinfection in the outdoor group were Bacillus cereus, Staphylococcus cephalosus and Staphylococcus haemolyticus. Comparison between groups showed that the residual rates of Cephalococcus and Staphylococcus epidermidis after skin disinfection in the outdoor group were significantly higher than those in the indoor group, and the P values were <0.05.Conclusion Although the current arm skin disinfection method can achieve the standard disinfection effect, there are still bacterial residues after disinfection, and the bacterial residue rate and residual microbial species may be related to the working environment of donors, this study can also provide a reference basis for the development of relevant standards or protocols.

Key words: Arm skin disinfection, Blood donor, Skin disinfectant, Bacterial identification, Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS)