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This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of Aeromonas isolates from clinical patients, tap water systems, and food. Ninety Aeromonas isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing (MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing. The 90 Aeromonas isolates were divided into 84 sequence types, 80 of which were novel, indicating high genetic diversity. The Aeromonas isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes act, aerA, alt, and ast found in 47 (52.2%), 13 (14.4%), 22 (24.4%), and 12 (13.3%) of the isolates, respectively. The majority of the isolates (≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol, gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new mcr-3 variant. Sequence type, virulence properties, and antibiotic resistance vary in Aeromonas isolates from clinical patients, tap water systems, and food. [ABSTRACT FROM AUTHOR]

Rivers are recognized as an important pathway for transport of microplastics (MPs) from land to sea, but limited information is available on the spatial distribution and seasonal variation of riverine MPs from upper reaches to estuaries. Such information is critical for source apportionment and development of effective management measures for riverine MPs. To fill the knowledge gap, we investigated the occurrence of MPs in surface water along an urban river in Guangzhou, southern China in wet and dry seasons. The abundances of MPs from 16 sampling sites in the wet and dry seasons varied from 0.123 to 1.84 particles m−3 and from 0.046 to 4.21 particles m−3, respectively. The spatial distribution of MP abundances showed an increasing trend from upstream to midstream and a decreasing trend from midstream to downstream and estuaries. The abundances of MPs peaked at the midstream, which is surrounded by a highly urbanized region with high population density (∼2530 persons per km2). The large surface water runoff during the wet season elevated the MP abundance in riverine water, except for that flowing through the central urban area where the abundance of MPs collected in the dry season was higher than that in the wet season. This was mainly ascribed to the large input from extensive anthropogenic activities and slow water flow rate in urban areas. The estimated monthly riverine MP fluxes from Humen, Hongqili, and Jiaomen were 7.42, 2.38, and 2.3 billion particles, respectively, in the wet season, and 0.86, 0.71, and 0.19 billion particles, respectively, in the dry season. An increase of riverine MP fluxes from Humen, Hongqili, and Jiaomen in the past three years was evident. The results from the present study provide valuable information for source apportionment of riverine MPs and support the initialization of possible MPs controlling measures. [Display omitted] • The main polymer types of microplastics (MPs) were polypropylene and polyethylene. • The MP abundances ranged in 0.123–1.84 and 0.046–4.21 particles m−3 in wet and dry season, respectively. • The maximum abundance of MPs in the Pearl River appeared in the urban area. • The spatial variation of MPs is more obvious in dry season than that in wet season. [ABSTRACT FROM AUTHOR]

• A disease occurrence characterized by fever and rash was monitored in China. • The etiological and epidemiological investigation was initiated. • We proved that a novel species of genus Ehrlichia was its pathogen. • We named the new species as " Candidatus Ehrlichia erythraense". From March to June 2021, the reported number of clinically diagnosed endemic typhus in Anhui and Hubei provinces of China nearly increased four-fold compared with the monthly average numbers in last 5 years. An etiological and epidemiological investigation was initiated. The clinical specimens from the reported patients and the potential vector ticks were collected for molecular and serological detection, as well as cell culturing assay to identify the potential pathogen. Polymerase chain reaction and sequence analysis of rrs and groEL showed that the pathogen from these patients was Ehrlichia sp., isolated from Haemaphysalis longicornis attached to these patients. The phylogenetic analysis based on 39 Ehrlichia genomes suggested that it should be taxonomically classified as a novel species, tentatively named " Candidatus Ehrlichia erythraense". A total of 19 of 106 cases were confirmed as Candidatus Ehrlichia erythraense infections by polymerase chain reaction, sequencing, and/or serological tests. The most frequent symptoms were fever (100%), rashes (100%), asthenia (100%), anorexia (100%), and myalgia (79%). The occurrence of the disease presenting with fever and rashes in Anhui and Hubei provinces was caused by a novel species of the genus Ehrlichia ; physicians need to be aware of this newly-discovered pathogen to ensure appropriate testing, treatment, and regional surveillance. [ABSTRACT FROM AUTHOR]

Objective: To conduct an etiological molecular epidemiological survey and laboratory test on a foodborne disease epidemic outbreak to make clear of the cause and implement effective prevention and control on it., Methods: On May 12th 2012, 135 kindergarten children were sent to Xuzhou City People's Hospital and Children's Hospital with gastrointestinal infection disease. A total of 34 anus swab samples and 4 vomit samples were collected from the patients. Real-time PCR rapid detection, strains separation and cultivation, phage lysis experiments, ATB automated identification system were used to make etiological detection and identification. The genomic DNA of salmonella enteritidis were typed with the pulsed-field gel electrophoresis (PFGE), cluster analysis were carried out together with the patterns of local Salmonella infections., Results: Children in 20 classes were suffered from the gastrointestinal infection among the 21 classes. There were no significant aggregation of class distribution. Among the 135 patients, 76 were boys (56.3%) and 59 were girls (43.7%). The main symptoms were fever (above 38°C), diarrhea and bellyache. Through real-time PCR detection and strains separation, 19 salmonella enteritidis were isolated from 34 anus swab samples of suspected cases and the detection rate was 56%. There were no strains detected from vomit samples. All of the 19 salmonella enteritidis showed the same serological subtype, biochemical reaction, drug sensitivity and phage lysis pattern. The salmonella enteritidis had the identical PFGE pattern (100% similarity), and were different from the pattern of local sporadic infection cases., Conclusion: It was confirmed that this was an epidemic outbreak of foodborne disease caused by homologous salmonella enteritidis by epidemiological survey, clinical information, lab etiological test and molecular typing.