ABSTRACT
To analyze the etiology and epidemiological characteristics of gastroenteritis virus in foodborne diseases from three cities in Shandong. From January to December 2017, six sentinel hospitals in Jinan, Yantai and Linyi city of Shandong Province were selected as the research sites. Stool samples of 1 397 diarrhea patients were collected, as well as basic information and clinical symptoms. Duplex quantitative RT-PCR was used to detect Norovirus genogroupⅠ (Nov GⅠ) and genogroupⅡ (Nov GⅡ), Sapovirus (SAV) and Human astrovirus (HAstV), respectively, quantitative RT-PCR was used to detect group A Rotavirus (RVA), and quantitative PCR was used to detect Enteric adenovirus (EAdV). The specific gene of the virus were sequenced and typed. It was compared that the gastroenteritis virus rate in cases with different characteristics and the clinical symptoms difference between the virus positive and negative cases. The median age ((25), (75)) was 23 (1, 42) , mainly male, 57.48% with 803 cased and children under 5 years old, 36.36% with 508 cases. The positive rate of gastroenteritis virus was 33.93% (474 cases), and that of Jinan, Linyi and Yantai City were 32.03% (147/459), 41.54% (189/455) and 28.57% (138/483), respectively (0.001). Nov GⅡ had the highest positive rate, 16.54% (231 cases), which, mainly GⅡ.P16/GⅡ.2 (48.28%, 56/116), peaked in May (24.75%, 50/202) and June (19.59%, 38/194). In patients of gastroenteritis virus positive, 44.51% (211/474) had vomiting symptoms, higher than that of patients of gastroenteritis virus negative (34.13%, 315/923). The difference was statistically significant (0.001). In Shandong Province, the majority of gastroenteritis patients were male and children under 5 years old. Nov GⅡ possessed highest epidemic intensity, and peaked in spring and summer. Viral gastroenteritis had atypical clinical symptoms.
ABSTRACT
Objective To study the characteristics and epidemic trend of Shigella in Shandong province through the analysis of serotype, virulence genes, molecular typing and drug sensitivity. Methods The serotype was classified using the method of slide agglutination. Polymerase chain reaction (PCR) was used to amplify the related virulence genes. The molecular typing was carried out by pulsed field gel electrophoresis (PFGE), and the antibiotic sensitivity of the strains was determined by micro-broth dilution method. Results The main serogroups of 44 Shigella strains were Shigella flexneri (54.55%) and Shigella sonnei (43.18%). The carrying rates of ipaH, Set1, Sen and ial were 100%, 43.18%, 56.82% and 50.00%, respectively. By PFGE typing, the strains of Shigella flexneri were divided into 18 patterns with a low similarity. The strains of Shigella sonnei were divided into 14 patterns, and the similarity of 89.47% of the strains was more than 90%. 44 strains of Shigella had different levels of resistance to 14 of the 15 antibiotics. 93.18% of the strains were multidrug resistant. Conclusion The Shigella in Shandong province is dominated by serogroups of Shigella flexneri and Shigella sonnei, with high virulence gene carrying rate, clustering distribution and severe antibiotic resistance. It is necessary to strengthen the monitoring on serotype, traceability and antibiotic resistance of Shigella in Shandong province.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the molecular subtypes of 73 strains of Yersinia enterocolitica biotype 1A isolated in Shandong province by PFGE, and thereby to analyze the relationship between PFGE typing and biological characteristics.</p><p><b>METHODS</b>Seventy-three strains of Yersinia enterocolitica biotype 1A were isolated from animal feces and meat products in Gaomi city and Wulian county in Shandong province from 2008 to 2009. Motility test, serum agglutination and virulent genes detection by PCR were used to learn the biological characteristics of the isolated strains. The molecular subtypes were determined by PFGE, whose relationships with motility, serotypes and virulent genotypes were also analyzed.</p><p><b>RESULTS</b>Out of the 73 strains of Yersinia enterocolitica, 5 showed medium-active motility while the other 68 showed well-active motility. The dominated serotypes were O:5(17/73) and O:8(14/73), followed by O:9(5/73) and O:7, 8(1/73), and there was no O:3 serotype found. Meanwhile, 36 strains couldn't be serotyped. All the strains were negative with the gene ail, ystA, yadA and virF, yet the positive rate of ystB gene was 72.6% (53/73). The 73 strains of Yersinia enterocolitica isolated could be subtyped into 54 PFGE patterns (K6GN11SD0001-K6GN11SD0054), most of which only had 1 or 2 isolated strains, and no pattern was dominant. The strains in the same or similar cluster were from different hosts; each serotype and toxic genotype scattered in the clustering trees, without specific correlation with PFGE subtypes. 4 out of 5 strains, which showed medium-active motility, belonged to one branch, with the similarity coefficient at 80.9% - 100.0%; while all the toxic genotype belonged to type B.</p><p><b>CONCLUSION</b>Biotype 1A Yersinia enterocolitica has many clones, whose PFGE types had relations with motility, but no relations with virulent genotype and host.</p>
Subject(s)
Bacterial Typing Techniques , DNA, Bacterial , Genetics , Electrophoresis, Gel, Pulsed-Field , Genes, Bacterial , Genotype , Meat Products , Microbiology , Yersinia enterocolitica , Classification , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To know the antibiotic resistance and molecular characteristics of Listeria monocytogenes in Shandong province and to study the relationship between antibiotic resistance phenotypes and genome types.</p><p><b>METHODS</b>From 2009 to 2010, a total of 80 Listeria monocytogenes isolates were collected from raw meat, cooked meat, aquatic products and other foods in 6 cities of Shandong province. The antibiotic susceptibility was measured by broth microdilution method, PFGE was performed for molecular typing and the relationship between antimicrobial resistance and PFGE patterns was analyzed.</p><p><b>RESULTS</b>16.25% (13/80) of the isolates were drug-resistant. Imipenem resistance was the most prevalent (12.50%, 10/80), followed by tetracycline and doxycycline (3.75%, 3/80 and 2.50%, 2/80). A total of the 80 isolates were subtyped into 9 antibiotic resistance patterns and 34 PFGE types which were largely dominated by the type 17 and 29. Antibiotic resistance pattern A corresponded to 79.41% (27/34) of PFGE types.</p><p><b>CONCLUSION</b>The antibiotic resistance of Listeria monocytogenes in Shandong province is serious from 2009 to 2010 and there is no correlation between PFGE types and antibiotic resistance patterns.</p>