Potential Risk of Transmission of Escherichia coli and Salmonella spp. Infections by the Musca domestica Fly and the Periplaneta americana Cockroach in the City of Cotonou (South Benin)

Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species of flies and cockroaches that cohabit with humans in the city of Cotonou and determine the contribution of Musca domestica and Periplaneta americana in the transmission of bacteria responsible for infections in humans. Methods: Capture sessions during the day for flies and at night for cockroaches were carried out in 4 arrondissements of the city of Cotonou. The insects collected were transported to the Center of Research Entomological of Cotonou for identification, then sent to the Section Hygiene of Water and Food for microbiological analysis, enumeration and testing for human pathogenic bacteria. Results: A total of 351 flies and 26 cockroaches were collected at the sites, including two synanthropic species belonging to two families each. Musca domestica and Periplaneta americana were the most abundant species found after identification in the city of Cotonou. Thermo-tolerant coliforms and Escherichia coli were found on all specimens at varying concentrations. Salmonella spp. bacteria were identified in the fly population from the Dantokpa dump. Conclusion: Flies and cockroaches can transmit microorganisms to humans. The presence of Salmonella spp. among the specimens revealed that infections frequently caused by contaminated food or water are also transmitted to humans by flies. The presence of these germs on flies and cockroaches represents a potential risk of mechanical transmission to humans. It is, therefore, essential to continue investigations in order to assess the species of bacteria propagated, improve control strategies against these troublesome insects and adopt better hygiene conditions for better living.

Multi-drug Resistant Uropathogenic Escherichia coli and Its Treatment by Chinese Medicine

Objectives： To investigate the resistance and virulence profiles of uropathogenic Escherichia coli（UPEC） and its treatment by Chinese medicine（CM） Fuzheng Qingre Lishi Formula（扶正清热利湿方, FQLF）. Methods： UPEC strains were isolated from recurrent urinary tract infections（UTIs） patients. Patient sensitivities to 17 antibiotics were tested by the disk diffusion method. Virulence genes were screened by plolymerase chain reaction. A mouse model was constructed using a multi-drug resistant and virulent UPEC strain and treated with FQLF or the antibiotic imipenem. The treatment efficacy was evaluated by bacterial clearance from urine and the urinary organs. Results： A total of 90 UPEC strains were collected, and 94.4% of the isolates were resistant to at least 1 antibiotic. Approximately 66.7% of the UPEC strains were multi-drug resistant. More than one virulence gene was found in 85.6% of the isolates. The extended-spectrum β-lactamases（ESBL）-positive strains were more resistant than the negative ones. The virulence gene number was positively correlated with the resistance number（P〈0.05）. A mouse model was successful y constructed using UPEC10. Treatment with either FQLF or antibiotics significantly cleared bacteria from the mouse urine after 14 days. In the untreated control, the bacteria lasted for 28 days. FQLF treatment of the UTI mouse model greatly reduced the bacterial number in the kidney and bladder, but could not completely clear the bacteria. Conclusions： Multi-drug resistance is common among UPEC isolates, and the resistance is positively related with virulence. FQLF could treat UPEC UTIs, but could not completely clear the bacteria from the host.

Characterization and complete genome sequence of vB_EcoP-Bp4,a novel polyvalent N4-like bacteriophage that infects chicken pathogenic Escherichia coli

Pathogenic Escherichia coli cause chicken colibacillosis, which is economically devastating to the poultry in- dustry worldwide （Bagheri et al., 2014）. Owing to in- creasing antibiotic resistance, phage therapy reagents have been developed to treat bacterial infections （Xu et al., 2015）.