Epidemiological characteristics and drug resistance surveillance of Shigella in infants and young children in Henan Province from 2013 to 2017 / 中华疾病控制杂志

Objective To investigate the pathogenic characteristics of Shigella in infants from 2013 to 2017 in Henan Province. Methods From 2013 to 2017, 606 Shigella strains were isolated from 5 149 children with diarrhea under 5 years old in Henan Province. Serotyping, drug sensitivity test and Polymerase Chain Reaction detection of virulence gene methods were used to detect the pathogen of Shigella. Results The detection rate of Shigella in children with diarrhea was 11.77%, and the highest detection rate was in the 1-2 age group(24.08%). 606 Shigella strains were divided into two groups and 11 serotypes. Shigella flexneri accounted for 73.43%， and Shigella sonnei accounted for 26.57%. Resistance of 176 Shigella strains to ampicillin and naphthidine was serious (resistance rate > 90%), and the resistance rates to chloramphenicol, ciprofloxacin, norfloxacin and compound sulfamethoxamine were higher than 65%, and the sensitivity of imipenem and cephalosporin were higher. There were differences in drug resistance between Shigella flexneri and Shigella sonnei. The virulence genes of infants were mainly shET-1+, shET-2+, ipaH+ and ial+, and 5 avirulent strains were detected. Conclusions The bacterial dysentery of infants in Henan Province is dominated by Shigella flexneri. There are serious resistance and multidrug resistance to common antibiotics, and the dominant genes in different serotyping strains are different.

Investigation on distribution of Yersinia enterocolitica in Henan province between 2005 and 2011 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the distribution of Yersinia enterocolitica in Henan province from 2005 to 2011.</p><p><b>METHODS</b>A total of 6700 samples of stool specimen were collected from diarrhea patients and different domestic animals between 2005 and 2011 from Zhengzhou, Suixian and Dengfeng, as well as flies and the daub specimens of raw and cooked meat products. The bacteria were isolated by cold enrichment method, analyzed by the systematic biochemistry to determine the serotypes and bio-types, and tested the virulence genes by PCR method.</p><p><b>RESULTS</b>A total of 216 strains of Yersinia enterocolitica were isolated from 11 kinds of animal hosts and foods, while 29.63% (64/216) of them were from swine. The dominant epidemic serotypes of the Yersinia enterocolitica were O: 5 and O: 8, accounted for 23.2% (50/216) and 20.4% (44/216), respectively; type 1A was the dominant bio-type, accounted for 84.7% (183/216). The dominant serotype and bio-type differed a lot among various hosts.16 pathogenic strains were isolated from swine, followed by diarrhea patients (6 strains) and dogs (6 strains).</p><p><b>CONCLUSION</b>The distribution of the host of Yersinia enterocolitica was widespread, while swine was the dominant animal host.</p>

Analysis of etiological surveillance results of Shigella spp between 2009 and 2010 in Henan province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the etiologic characteristics of bacillary dysentery found in Henan province, between year 2009 and 2010.</p><p><b>METHODS</b>In order to explore the distribution of bacterial types, drug susceptibility and the virulence gene carrier situation, 482 strains of Shigella isolated in Henan province between 2009 and 2010 were pathogen-detected and analyzed by serotype screening, anti microbial sensitivity test and PCR methods.</p><p><b>RESULTS</b>The 482 isolated strains were confirmed to be Shigella by both morphological and biochemical tests. The Shigella strains were divided into 13 serotypes in 2 groups, namely Shigella flexneri (B group) accounting for 72.0% (347/482) and Shigella sonnei (D group), accounting for 28.0% (135/482). The detection rate of Serotype F2a, as the dominant type of Shigella flexneri, decreased from 43.4% (106/245) in 2009 to 33.8% (80/237) in 2010; while the detection rate of Shigella sonnei increased from 13.1% (32/245) to 43.5% (103/237) in the same period. The results of microbial sensitivity tests carried out in year 2009 and 2010, both showed that over 98% of the 185 studied strains were resistant to ampicillin (AMP), trimethoprim-pyrimidine (TMP), tetracycline (TE), streptomycin (S) and nalidixic acid (NA).182 strains were recruited in the virulence factors detection, 67.6% (123/182) of which carried Shigella Enterotoxin 1B (set1B), Shigella Enterotoxin 2 (set2), invasive plasmid antigen H (ipaH) or invasion-related virulence factors (ial) and 24.2% (44/182) of which carried 3 virulence factors mentioned above.</p><p><b>CONCLUSION</b>The prevalent serotypes of Shigella in Henan province have changed in recent years. The isolated strains showed high resistance to common antibacterial drugs and generally carried virulence factors.</p>

Etiology survey on an outbreak of viral encephalitis / 中华预防医学杂志

<p><b>OBJECTIVE</b>To isolate and identify the pathogen that caused an outbreak of viral encephalitis in Henan province in 2010; and to analyze the genetic characteristic of gene viral protein1(VP1) on the viral strains isolated.</p><p><b>METHODS</b>During the period of the outbreak of viral encephalitis in Lushan county, Pingdingshan city, Henan province, eight hospitalized patients were recruited in the study. All the patients' feces samples were collected. Three patients' cerebrospinal fluids samples and another four patients' serum samples were collected separately. The virus in the samples were isolated and identified by enterovirus (EV) combined serum. The VP1 gene of the positive isolate was amplified by reverse transcriptase PCR method, and its nucleotide sequence was detected and the genetic evolution was analyzed.</p><p><b>RESULTS</b>Fifteen samples were collected in total, including 8 feces samples, 3 cerebrospinal fluids samples and 4 serum samples. The results of Fluorescence Quota PCR detection showed that 11 out of 15 samples were positive; 2 strains of virus were isolated from 2 feces samples and the serotype were all Coxsackie-positive identified by the EV combined serum. The full-length VP1 genetic sequences were all 849 bp, and showed 77.1% - 96.9% similar to the nucleotide and 95.8% - 100% similar to the amino acid of CoxB5. The analysis showed that the genetic evolution tree was just the same with Genotype-D.</p><p><b>CONCLUSION</b>CoxB5 whose genotype was Genotype-D, was the pathogen that caused the outbreak of viral encephalitis in Lushan county, Pingdingshan city, Henan province.</p>