Flies as a potential vector of selected alert pathogens in a hospital environment

How to prove neglect in the context of the post-mortem examination

Understanding the causes, extent, and period of neglect is not only a medical but also a forensic task when it comes to legal investigations. In this study, we evaluated 46 autopsied cases where there was clear evidence of physical neglect during the last period of the deceased's life. The age of the deceased ranged from 21 to 96 years; most of them were female (71.7%). The majority of cases (89.9%) took place in a domestic environment, with partners or relatives providing care. The most frequent post-mortem findings were pressure sores, followed by inflammatory skin changes, and signs of malnutrition and dehydration. Neglect was the cause or co-cause of death in 23% of the cases. More than half of the deceased showed severe contamination of the skin surface by excrement, and in almost 40% of the cases, fly infestation was found. The majority of insects belonged to the group of house flies (Diptera: Muscidae), mainly the common house fly, Musca domestica. By analyzing the entomological evidence, it was possible to prove an insect infestation period of at least several days ante-mortem. Since the period of neglect may be relevant in terms of legal proceedings, the present work demonstrates the particular importance of insect traces in providing this evidence. While prosecution and conviction of caregivers remain challenging, it is all the more essential that entomology and legal medicine collaborate on the analysis of findings of neglect.

Hospital Wastes as Potential Sources for Multi-Drug-Resistant ESBL-Producing Bacteria at a Tertiary Hospital in Ethiopia

The hospital environment is increasingly becoming an important reservoir for multi-drug-resistant (MDR) Gram-negative bacteria, posing serious challenges to efforts to combat antimicrobial resistance (AMR). This study aimed to investigate the role of hospital waste as a potential source of MDR ESBL-producing bacteria. Samples were collected from multiple sources within a hospital and its vicinity, including surface swabs, houseflies, and sewage samples. The samples were subsequently processed in a microbiology laboratory to identify potential pathogenic bacteria and confirmed using MALDI-TOF MS. Bacteria were isolated from 87% of samples, with the predominant isolates being E. coli (30.5%), Klebsiella spp. (12.4%), Providencia spp. (12.4%), and Proteus spp. (11.9%). According to the double disc synergy test (DDST) analysis, nearly half (49.2%) of the bacteria were identified as ESBL producers. However, despite exhibiting complete resistance to beta-lactam antibiotics, 11.8% of them did not test positive for ESBL production. The characterization of E. coli revealed that 30.6% and 5.6% of them carried blaCTX-M group 1 type-15 and blaNDM genes, respectively. This finding emphasizes the importance of proper hospital sanitation and waste management practices to mitigate the spread of AMR within the healthcare setting and safeguard the health of both patients and the wider community.

Flies as Vectors and Potential Sentinels for Bacterial Pathogens and Antimicrobial Resistance: A Review

The unique biology of flies and their omnipresence in the environment of people and animals makes them ideal candidates to be important vectors of antimicrobial resistance genes. Consequently, there has been increasing research on the bacteria and antimicrobial resistance genes that are carried by flies and their role in the spread of resistance. In this review, we describe the current knowledge on the transmission of bacterial pathogens and antimicrobial resistance genes by flies, and the roles flies might play in the maintenance, transmission, and surveillance of antimicrobial resistance.

Infections Caused by Moellerella wisconsensis: A Case Report and a Systematic Review of the Literature

Background: Moellerella wisconsensis, a member of the family of Enterobacteriaceae, although isolated widely in nature, rarely causes infections in humans. Herein, we report a case of isolation of M. wisconsensis from pigtail end culture, urine culture and blood culture in a 76-year-old patient. Objective: To systematically address all the relevant information regarding M. wisconsensis through literature. Methods: We searched PubMed and Scopus databases up to January 2022 and performed a qualitative synthesis of published articles reporting infection from M. wisconsensis in humans. Results: We identified 25 records on PubMed and 43 additional records on Scopus. After removing duplicates, we examined in detail 15 articles. Ten studies with a total of 17 cases were included in our systematic review. Nine studies described isolated case reports, while 1 study described 8 cases. The origin of the infection was the alimentary tract in 9 cases, gallbladder in 4 cases, peritoneal cavity in 2 cases, respiratory tract in 1 case and hemodialysis catheter insertion site in 1 case. In 3 of the aforementioned cases M. wisconsensis was also isolated in blood cultures. Conclusion: Physicians should be aware that M. wisconsensis can be present in multiple clinical specimens and that the antibiotic resistance profile of the isolates may pose significant challenges.

ESBL-Producing Moellerella wisconsensis—The Contribution of Wild Birds in the Dissemination of a Zoonotic Pathogen

Simple Summary

Moellerella wisconsensis is a potentially zoonotic pathogen that has sporadically been isolated from animals and humans. In the present study, we describe the occurrence of the organism among 445 wild bird and 2000 human fecal samples, in the context of an investigation regarding antimicrobial resistant bacteria in Greece. According to our results, 0.9% (n = 4) of the examined wild birds were found to be colonized by M. wisconsensis, while no human was a carrier of the bacterium. Out of the total number of four M. wisconsensis strains that we detected, three presented resistance to 3rd generation cephalosporins, were phenotypically confirmed to produce extended spectrum beta lactamases (ESBLs) and harbored bla_CTX-M-1. Resistance to tetracyclines, aminoglycosides and trimethoprim/sulfamethoxazole was additionally detected in three, two and one of the ESBL isolates, respectively. This is the first report that presents the dissemination of M. wisconsensis in wild bird from Greece and describes CTX-M-1 production in multidrug resistant wild birds’ isolates of this bacterial species.

Abstract

Moellerella wisconsensis is an Enterobacteriaceae with unclarified dispersion and pathogenicity. During an ongoing investigation about antimicrobial resistance in Greece, the occurrence of M. wisconsensis was evaluated among wild birds and humans. A total of 445 wild bird and 2000 human fecal samples were collected and screened for the presence of the organism. Subsequently, all M. wisconsensis strains were phenotypically and molecularly characterized regarding their antimicrobial resistance characteristics. Four M. wisconsensis were isolated from a common pheasant (Phasianus colchicus), two Eurasian magpies (Pica pica) and a great white-fronted goose (Anser albifrons). Among these four strains, the three latter presented resistance to 3rd generation cephalosporins, were phenotypically confirmed to produce ESBLs and were found to harbor bla_CTX-M-1. The three ESBL isolates additionally exhibited resistance to tetracyclines, while resistance to aminoglycosides was detected in two of them and to trimethoprim/sulfamethoxazole in one. No Moellerella wisconsensis strains were retrieved from the human samples tested. This is the first report that provides evidence of M. wisconsensis dissemination among wild birds in Greece, describing CTX-M-1 production in multidrug resistant wild birds’ isolates of this bacterial species.