Detection Of Drug-resistant Bacteria In Microbial Aerosol

Aerosols are sol systems formed by solid or liquid particles suspended in a gaseous medium,in which microbial aerosols account for a large part.Microorganisms such as fungi,bacteria,and viruses in microbial aerosols pose a threat to public health,and research has shown that aerosols are also a way of transmitting disease.Therefore,the effective collection and research of the composition and abundance of microorganisms in microbial aerosols are of great significance in preventing airborne diseases.This thesis mainly developed a high-efficiency liquid impact sampler based on a rotating liquid cavity.the device was used to collect environmental microorganisms.And the resistance of aerosol microorganisms was investigated.The main conclusions are as follows:(1)A new type of liquid impact aerosol sampler based on a rotating liquid cavity for efficient collection of microbial living organisms in a microbial aerosol was developed.The device can significantly improve the collection efficiency of experimental strains of Escherichia coli and Aspergillus spores in a laboratory microbial aerosol system.The collection efficiency in the air environment is also much higher than the method of liquid impact and natural settlement.(2)This device was used to monitor the culturable microorganisms in microbial aerosols under different weather conditions such as rain,snow,and cloudy.It was found that the living microorganisms in the microbial aerosol reached 333±58 CFU/m~3 under light rain conditions,292±83 CFU/m~3 on snowy days,and 250±42 CFU/m~3 on cloudy days.(3)The device was used to monitor microbial aerosols at the entrance of Beijing subway station for one week.We also record real-time environmental factors.The results show that the microbial aerosol concentration in the subway is low,the highest is 48±24 CFU/m~3.Multivariate analysis showed that the bacterial aerosol concentration at the subway station was highly correlated with temperature,and the fungal aerosol concentration was highly correlated with the human flow.(4)16S rDNA sequencing analysis of bacteria showed that the aerosol in the subway station contains at least 27 genera of bacteria,and drug resistance studies were conducted on potential pathogenic bacteria of the genus Kocuria,Micrococcus,Bacillus,and Staphylococcus.Among them,two strains of ampicillin-resistant Staphylococcus were found.This article mainly developed a new method of microbial aerosol sampling.It was evaluated in a laboratory system and proved to have the potential for practical application by applying to an outdoor environment.It is hoped that in the future research,the research in the field of microbial aerosols can be added.