Salmonellosis outbreak archive in China: data collection and assembly.

Infectious disease outbreaks transcend the medical and public health realms, triggering widespread panic and impeding socio-economic development. Considering that self-limiting diarrhoea of sporadic cases is usually underreported, the Salmonella outbreak (SO) study offers a unique opportunity for source tracing, spatiotemporal correlation, and outbreak prediction. To summarize the pattern of SO and estimate observational epidemiological indicators, 1,134 qualitative reports screened from 1949 to 2023 were included in the systematic review dataset, which contained a 506-study meta-analysis dataset. In addition to the dataset comprising over 50 columns with a total of 46,494 entries eligible for inclusion in systematic reviews or input into prediction models, we also provide initial literature collection datasets and datasets containing socio-economic and climate information for relevant regions. This study has a broad impact on advancing knowledge regarding epidemic trends and prevention priorities in diverse salmonellosis outbreaks and guiding rational policy-making or predictive modeling to mitigate the infringement upon the right to life imposed by significant epidemics.

Mobilome-driven partitions of the resistome in Salmonella.

IMPORTANCE: Antimicrobial resistance (AMR) has become a significant global challenge, with an estimated 10 million deaths annually by 2050. The emergence of AMR is mainly attributed to mobile genetic elements (MGEs or mobilomes), which accelerate wide dissemination among pathogens. The interaction between mobilomes and AMR genes (or resistomes) in Salmonella, a primary cause of diarrheal diseases that results in over 90 million cases annually, remains poorly understood. The available fragmented or incomplete genomes remain a significant limitation in investigating the relationship between AMR and MGEs. Here, we collected the most extensive closed Salmonella genomes (n = 1,817) from various sources across 58 countries. Notably, our results demonstrate that resistome transmission between Salmonella lineages follows a specific pattern of MGEs and is influenced by external drivers, including certain socioeconomic factors. Therefore, targeted interventions are urgently needed to mitigate the catastrophic consequences of Salmonella AMR.

A Cross-Sectional Study of Companion Animal-Derived Multidrug-Resistant Escherichia coli in Hangzhou, China.

Antimicrobial resistance poses a challenge to global public health, and companion animals could serve as the reservoir for antimicrobial-resistant bacteria. However, the prevalence of antimicrobial-resistant bacteria, especially multidrug-resistant (MDR) bacteria, and the associated risk factors from companion animals are partially understood. Here, we aim to investigate the prevalence of MDR Escherichia coli, as an indicator bacterium, in pet cats and dogs in Hangzhou, China, and evaluate the factors affecting the prevalence of MDR E. coli. The proportion of pets carrying MDR E. coli was 35.77% (49/137), i.e., 40.96% (34/83) for dogs and 27.28% (15/54) for cats. Isolates resistant to trimethoprim-sulfamethoxazole (49.40% and 44.44%), amoxicillin-clavulanic acid (42.17% and 38.89%), and nalidixic acid (40.96% and 35.19%) were the most prevalent in dogs and cats. Interestingly, comparable prevalence of MDR E. coli was observed in pet dogs and cats regardless of the health condition and the history of antibiotic use. Genetic diversity analysis indicates a total of 86 sequencing types (23 clonal complexes), with ST12 being the most dominant. Further genomic investigation of a carbapenem-resistant E. coli ST410 isolate reveals abundant antimicrobial-resistance genes and a plasmid-borne carbapenemase gene (NDM-5) flanked by insertion sequences of IS91 and IS31, suggesting the plasmid and insertion sequences may be involved in carbapenem-resistance dissemination. These data show that companion animal-derived MDR bacteria could threaten public health, and further regulation and supervision of antimicrobial use in pet clinics should be established in China. IMPORTANCE MDR Escherichia coli are considered a global threat because of the decreasing options for antimicrobial therapy. Companion animals could be a reservoir of MDR E. coli, and the numbers of pets and households owning pets in China are booming. However, the prevalence and risk factors of MDR E. coli carriage in Chinese pets were rarely studied. Here, we investigated the prevalence of MDR E. coli in pets in Hangzhou, one of the leading cities with the most established pet market in China, and explored the factors that affected the prevalence. Our findings showed high prevalences of MDR E. coli in pet dogs and cats regardless of their health condition and the history of antibiotic use, suggesting their potential role of public health risk. A call-to-action for improved regulation of antimicrobial use in companion animal is needed in China.

Infant food production environments: A potential reservoir for vancomycin-resistant enterococci non-nosocomial infections.

Enterococcus has been considered one of the most important nosocomial pathogens for human infections, and the hospital environment is an important reservoir for vancomycin-resistant enterococci (VRE) that leads to antimicrobial therapeutic failure. However, infant foods and their production environments could pose risks for the immature population, while this question remains unaddressed. This study conducted an extensive and thorough Enterococcus isolation, VRE risk assessment of the Chinese infant food production chains and additional online-marketing infant foods, including powdered infant formula (PIF) and infant complementary food (ICF). To investigate the prevalence of Enterococcus along infant food chains and commodities, a total of 482 strains of Enterococcus, including E. faecium (n = 363), E. faecalis (n = 84), E. casseliflavus (n = 13), E. mundtii (n = 12), E. gallinarum (n = 4), E. hirae (n = 4), and E. durans (n = 2) were recovered from 459 samples collected from infant food production chains (71/254) and food commodities (67/205). A decreasing trend for Enterococcus detection rate was found in the PIF production chain (PIF-PC), particularly during the preparation of the PIF base powder (From 100 % in raw milk to 8.70 % in end products), while an increasing trend was observed in the ICF production chain (ICF-PC) mainly during the initial processing of farm crops and the further processing of the product (20 % at farm crops increasing to 76.92 % at end products). The result indicated that the PIF-PC process effectively reduced Enterococcus contamination, while the ICF-PC showed the opposite trend. Importantly, eleven VRE isolates were recovered from the infant food production chain, including seven E. casseliflavus isolates carrying vanC2/C3 and four E. gallinarum isolates carrying vanC1. Ten VRE isolates were from food production environments. Collectively, our study demonstrated that infant food production environments represent potential reservoirs for VRE non-nosocomial infections in vulnerable populations.

Prevalence and Genomic Investigation of Multidrug-Resistant Salmonella Isolates from Companion Animals in Hangzhou, China.

Salmonella is a group of bacteria that constitutes the leading cause of diarrheal diseases, posing a great disease burden worldwide. There are numerous pathways for zoonotic Salmonella transmission to humans; however, the role of companion animals in spreading these bacteria is largely underestimated in China. We aimed to investigate the prevalence of Salmonella in pet dogs and cats in Hangzhou, China, and characterize the antimicrobial resistance profile and genetic features of these pet-derived pathogens. In total, 137 fecal samples of pets were collected from an animal hospital in Hangzhou in 2018. The prevalence of Salmonella was 5.8% (8/137) in pets, with 9.3% (5/54) of cats and 3.6% (3/83) of dogs being Salmonella positive. By whole-genome sequencing (WGS), in silico serotyping, and multilocus sequence typing (MLST), 26 pet-derived Salmonella isolates were identified as Salmonella Dublin (ST10, n = 22) and Salmonella Typhimurium (ST19, n = 4). All of the isolates were identified as being multidrug-resistant (MDR), by conducting antimicrobial susceptibility testing under both aerobic and anaerobic conditions. The antibiotics of the most prevalent resistance were streptomycin (100%), cotrimoxazole (100%), tetracycline (96.20%), and ceftriaxone (92.30%). Versatile antimicrobial-resistant genes were identified, including floR (phenicol-resistant gene), blaCTX-M-15, and blaCTX-M-55 (extended-spectrum beta-lactamase genes). A total of 11 incompatible (Inc) plasmids were identified, with IncA/C2, IncFII(S), and IncX1 being the most predominant among Salmonella Dublin, and IncFIB(S), IncFII(S), IncI1, and IncQ1 being the most prevailing among Salmonella Typhimurium. Our study applied WGS to characterize pet-derived Salmonella in China, showing the presence of MDR Salmonella in pet dogs and cats with a high diversity of ARGs and plasmids. These data indicate a necessity for the regular surveillance of pet-derived pathogens to mitigate zoonotic diseases.

Nanoporous silver nanorods as surface-enhanced Raman scattering substrates.

Structures with dense nanopores are desirable as surface-enhanced Raman scattering (SERS) sensing substrates because the nanopores can behave as both analyte containers and SERS-active sites (known as hot spots). Inspired by the dealloying process to prepare nanoporous structures through selectively removing active metals from their alloy, we developed a method to prepare nanoporous Ag nanorods through chemical reduction of the electrodeposited Ag7O8NO3 nanorods using a strong reducing agent (e.g., NaBH4). The length and the thickness of the Ag7O8NO3 nanorods could be controlled by the electrodeposition voltage and time. Nitrogen and oxygen elements were immediately removed from Ag7O8NO3 nanorods by the reducing agent, leaving behind a tremendous number of nanopores with a mean size of 20 nm, which can efficiently trap and enrich analytes. Meanwhile, the densely packed nanopores can behave as SERS hot spots to provide strong SERS enhancement. The nanoporous Ag nanorods as SERS substrates were used to sensitively detect adenine, spike glycoprotein, and polychlorinated biphenyls pollutants, as well as identify different types of bacteria. The simple fabrication process and the outstanding SERS performance of the nanoporous Ag nanorods make them promising candidates for SERS applications towards trace detection of pollutants, narcotics, food additives, and biomolecules.