2.Multi-PCR identification and virulence genes detection of Campylobacter jejuni isolated from China.
Mao-jun ZHANG ; Yi-xin GU ; Lu RAN ; Jian-zhong ZHANG
Chinese Journal of Epidemiology 2007;28(4):377-380
OBJECTIVEThis study was to simultaneously identify Campylobacter jejuni and Campylobacter coli isolates in China by Multi-PCR assay and to study the prevalence of six virulence and toxin genes on them.
METHODSA multi-PCR method with three sets of primers specifically designed for application of a 16S rRNA as a universal control, mapA, ceuE based on the specific sequence of C. jejuni and C. coli, was applied to detect 65 Campylobacter isolates from China. Another two separately PCR Primers were directed towards the hippuricase gene (hipO) characteristic of C.jejuni and glyA gene characteristic of C. coli were performed for further confirmation. The presence of the cadF, virB11, flaA, cdtA, cdtB, cdtC genes among these 65 strains were investigated by PCR.
RESULTSFrom multi-PCR detection, 42 isolates belonged to C. jejuni, other 23 isolates belong to C. coli. Data showing the identification were 100% in concordance with the separated PCR for hipO and glyA amplification. The efficiency (100%) of identification by these three primers multi-PCR method was higher than the biochemical test (83.1%). The cadF and flaA genes were detected from 100% (65/65) of the isolates and the PCR product of each gene were identical with each isolate. Only 10.8% (7/65) of the isolates were positive for virB11. The cdtA gene was found in 92% (60/65) of the isolates. 97.6% (41/42) of C. jejuni had cdtB gene, whereas no PCR product with this primers for all the C. coli isolates. cdtC was presented in all the isolates but the lengths of PCR products were different. For C. jejuni, it was 555 bp, for C. coli, it was about 465 bp.
CONCLUSIONThis three primers simultaneous multi-PCR method seemed to be useful for the identification of C. jejuni and C. coli isolates from China since cadF and flaA genes were widely spread in Campylobacter isolates in this country. The present report on virB11 was similar to previous reports from other countries, but the distribution of cdt gene cluster in Campylobacter species isolated from China might be different.
Campylobacter coli ; genetics ; isolation & purification ; pathogenicity ; Campylobacter jejuni ; genetics ; isolation & purification ; pathogenicity ; China ; DNA Primers ; Genes, Bacterial ; Polymerase Chain Reaction ; Virulence ; genetics
3.Etiological analysis of enteric infectious diseases during Beijing Olympic Games.
Fang HUANG ; Mei QU ; Yuan LIU ; Han-qiu YAN ; Zhi-yong GAO ; Xiang-feng DOU ; Hai-yan ZHANG ; Zhen ZHANG ; Jian-xin MA ; Jing GUO
Chinese Journal of Preventive Medicine 2009;43(9):789-792
OBJECTIVETo understand pathogen patterns of enteric infectious diseases and its impact on this pattern due to aggregation of a great deal of foreign visitors during Beijing Olympic Games.
METHODSThe diarrheal patient's rectal swabs and stool specimens were collected from Olympic stadium and hospitals of four districts, including Dongcheng, Xicheng, Haidian and Chaoyang. Enteric multiple pathogens were detected from the total 45 specimens. The culture method was used for the enteric bacteria, ELISA and RT-PCR for the enteric viruses. Molecular typing of Salmonella Enteritidis isolation was completed by PFGE.
RESULTSIt was found that 26 out of 45 cases were positive with 57.8 percent for pathogen detection, and 24 were identified as enteric pathogenic bacteria, including Vibrio parahaemolyticus, Salmonella, diarrheagenic Escherichia coli and Campylobacter jejuni, two as norovirus. There were mixed infections of two pathogenic bacteria for three cases. Ten kinds of pathogens were detected from foreign cases, while five kinds from Chinese cases. A total of 5 PFGE patterns were identified in 10 Salmonella Enteritidis isolates from national and foreign diarrheal cases, which were concentrative in some extent.
CONCLUSIONVibrio parahaemolyticus, Salmonella, diarrheagenic Escherichia coli and Campylobacter jejuni were found to be the primary bacterial pathogens during the Olympic Games. Enteric virus infection existed in summer diarrhea.
Adult ; Bacterial Typing Techniques ; Campylobacter jejuni ; classification ; isolation & purification ; China ; Diarrhea ; epidemiology ; etiology ; microbiology ; virology ; Enterobacteriaceae ; classification ; isolation & purification ; Enterovirus ; isolation & purification ; Escherichia coli Infections ; microbiology ; Female ; Humans ; Male ; Salmonella ; classification ; isolation & purification ; Shigella ; classification ; isolation & purification ; Sports ; Vibrio parahaemolyticus ; classification ; isolation & purification