The portable detector ImmunoSMART was combined with the cyclone air sampler to detect the model bioagent E. coli DH5a in bioaerosols. The selected capture antibody was immobilized on gold electrodes, antibody-peroxidase conjugate served as a tracer. In buffer, the amperometric immunosensor measured 10 3 to 10 8 CFU/mL within 30 min. Detection in air was realized in a closed aerosol chamber. Automated dissemination of the cells, sampling and measurement allowed remote testing of the cyclone/immunodetector. The level of 150 CFU/L in air was clearly indicated (20 min analysis including 5 min sampling) and independently confirmed using the slit sampler and agar cultivation. The results seem promising for further extended tests in both aerosol chamber and field trial conditions.

Since the occurrence of E. coli B2-O25b-ST131 CTX-M-27 was only recently described in Asia, the frequent isolation of this lineage among patients in South Moravia suggests an efficient transfer of this clone from Asian countries. The limited variability of detected parameters of ESBL-producing UPEC strains is consistent with a common origin of the analyzed isolates, in which there is an ongoing process of genetic diversification.

These findings suggest a potential to detect ESBL strains based on virulence factors and biochemical properties, which could be useful in shaping proper empiric antimicrobial therapy, and for initiating such therapy as soon as possible.