Enterobacteria identification and detection of diarrheagenic Escherichia coli in a Port Complex

Detection of Escherichia coli and other Enterobacteriales members in seabirds sampled along the Brazilian coast

Escherichia coli, an Enterobacterales member, is a normal representative of the microbiota of homeothermic animals. Most strains are commensal, but several pathotypes can cause disease, and numerous antimicrobial resistance factors have been identified. These bacteria have spread rapidly in recent years, highlighting the importance of screening the environment and non-human reservoirs for virulent strains and/or those presenting resistance factors, in addition to other microorganisms of public health importance. In this context, this study aimed to survey Enterobacteriales present in seabirds sampled along the Brazilian coast, comparing findings between migratory and resident birds, as well as between wrecked and non-wrecked animals. Escherichia coli pathotypes were also characterized through rapid seroagglutination and polymerase chain reaction techniques and antimicrobial resistance profiles were investigated through the disc agar diffusion method. Cloacal, ocular, oral, tracheal, and skin lesion swabs, as well as fresh feces, were collected from 122 seabirds. The findings indicate these animals as important hosts for opportunistic human pathogens. Escherichia coli strains were identified in 70 % of the analyzed seabirds, 62 % of which displaying resistant or intermediate profiles to at least one antimicrobial, while 7% were multiresistant. Resistance to tetracycline (22 %), nalidixic acid (15 %), trimethoprim-sulfamethozaxol (14 %) and ampicillin (12 %) were the most prevalent. Resistance to cefoxitin, a critically important antimicrobial for human medicine, was also detected. Virulence genes for one of the EAEC, ETEC or EPEC pathotypes were detected in 30 % of the identified strains, the first two described in seabirds for the first time. The EAEC gene was detected in 25 % of the sampled seabirds, all resident, 8 % of which exhibited a multidrug-resistant profile. Thus, seabirds comprise important reservoirs for this pathotype. Escherichia coli was proven an ubiquitous and well-distributed bacterium, present in all evaluated bird species and sampling sites (except Marajó Island). According to the chi-square test, no significant differences between E. coli prevalences or antimicrobial resistance profiles between migratory and resident and between wrecked and non-wrecked seabirds were observed. Thus, migratory birds do not seem to contribute significantly to E. coli frequencies, pathotypes or antimicrobial resistance rates on the Brazilian coast.

Determination of the Microbial and Chemical Loads in Rivers from the Quito Capital Province of Ecuador (Pichincha)-A Preliminary Analysis of Microbial and Chemical Quality of the Main Rivers

Contamination of natural water sources is one of the main health problems worldwide, which could be caused by chemicals, metals, or microbial agents. This study aimed to analyze the quality of 18 rivers located in Quito, the capital province of Pichincha, Ecuador, through physico-chemical and microbial parameters. The E. coli and total coliforms assessments were performed by a counting procedure in growth media. Polymerase chain reaction (PCR) was realized to detect several microbial genera, as well as Candida albicans, two parasites (Cryptosporidium and Giardia spp.) and E. coli pathotypes: enterohemorrhagic E. coli (EHEC), enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC) and enteropathogenic E. coli (EPEC). Additionally, physico-chemical parameters and major and trace metals were analyzed in each surface water sample. Our results demonstrated that most of the rivers analyzed do not comply with the microbial, physico-chemical, and metal requirements established by the Ecuadorian legislation. In terms of microbial pollution, the most polluted rivers were Monjas, Machángara, Pisque, and Pita Rivers. Furthermore, three out of four analyzed E. coli pathotypes (EIEC, EHEC, and EAEC) were detected in certain rivers, specifically: Monjas River showed the presence of EIEC and EHEC; in the Machángara River, EAEC and EIEC were detected; and finally, EIEC was present in the Guayllabamba River. Several physico-chemical parameters, such as pH, COD_total, and TSS values, were higher than the Ecuadorian guidelines in 11, 28, and 28% of the rivers, respectively. Regarding heavy metals, Zn, Cu, Ni, Pb, Cd, and Mn surpassed the established values in 94, 89, 61, 22, 22, and 17% of the rivers, respectively. Machangara River was the only one that registered higher Cr concentrations than the national guidelines. The values of Al and Fe were above the recommended values in 83 and 72% of the rivers. Overall, based on the physical-chemical and microbiological parameters the most contaminated rivers were Machángara and Monjas. This study revealed severe contaminations in Ecuadorean Rivers; further studies should evaluate the sources of contamination and their impact on public health.

Prevalence of diarrheagenic Escherichia coli in animal products in Duhok province, Iraq

BACKGROUND

Diarrheagenic Escherichia coli (DEC) is regarded as a great public health concern all around the world causing diarrhoea which can be transmitted through food chain.

AIMS

This study aimed to determine the contamination level and exact distribution rate of DEC in food products consumed by human.

METHODS

Seven hundred and twenty samples of food from animal origin and fishes were analysed by conventional and molecular method for the presence of E. coli and two multiplex polymerase chain reaction (mPCR) for detection of DEC.

RESULTS

Two hundred and eighty-three E. coli isolates were detected. The classification of DEC by two multiplex PCR assay yielded 84 DEC pathotypes. Enterotoxigenic E. coli (ETEC) was detected at high rates (75%) followed by shiga-toxigenic E. coli (STEC) and enterohemorrhagic E. coli (EHEC) (each of 9.5%), enteroaggregative E. coli (EAEC) (3.5%) and atypical enteropathogenic E. coli (aEPEC) (about 2.3%). The highest number of DEC (n=26; 21.6%) was observed from beef carcasses in abattoir while the lowest number (n=7; 5.8%) was noticed from burger samples (P<0.01). Enterotoxigenic E. coli was widespread in local raw ground meat and fish surface swabs (P<0.001), EAEC (P<0.01), and EHEC (P<0.001) were only in beef carcasses swabs, STEC was more prevalent in both imported and local raw burger (P<0.01), while the isolates of aEPEC were from imported chicken carcasses (P>0.05).

CONCLUSION

High DEC contamination rate that was observed is attributed to the poor hygienic practices during food processing. Therefore, a superior hygienic application is required.

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa

Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert^®18/Quanti-Tray^® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.