1.Genetic characteristics of coxsackievirus A16 strains isolated in Liaocheng city in Shandong province ;during 2013
Guangyin XU ; Yaowen PEI ; Shiying ZHANG ; Zhiyu WANG
Chinese Journal of Microbiology and Immunology 2015;(4):253-257
Objective To study the etiological agent of hand, foot and mouth disease ( HFMD) and the genetic characteristics of coxsackievirus A16 ( CVA16 ) strains isolated from clinical specimens of patients with HFMD in Liaocheng city in 2013.Methods Throat swab and stool specimens were collected from patients with HFMD in the disease surveillance hospitals in Liaocheng city from January to December 2013.Samples pos-itive for CVA16 strains were screened out for the isolation of virus strains with rhabdomyosarcoma ( RD) cells and Vero cells.The entire VP1 coding regions of 9 randomly selected CVA16 isolates were amplified and se-quenced.BioEdit and MEGA4 softwares were used for homology analysis.A phylogenetic tree among the 9 CVA16 isolates and 56 CVA16 representative strains of known genotypes and subgenotypes was constructed.Re-sults The results of PCR analysis showed that 747(77.73%) out of 961 specimens were positive for HFMD and among them, 74 samples (9.91%) were positive for EV71 strains, 130(17.40%) were CVA16 strains and 543(72.69%) were other enterovirus strains.The 9 CVA16 strains clustered into the B2b evolution branch of B genotype with the representative strains, sharing 97.7%to 100%homologies in nucleotide sequences and 99.3%to 100%in amino acid sequences.Conclusion Although EV71 and CVA16 strains were identified, other enteric viruses were the predominant pathogens causing HFMD in Liaocheng city in 2013.The CVA16 iso-lates belonged to B2b subgenotype.The pathogen spectrum of HFMD had already changed.It is necessary to strengthen the surveillance for EV71, CVA16 and other enteric viruses and understand their genetic characteriza-tions, which would be of great significance for the prevention and control of HFMD.
2.Molecular epidemiology of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa in rural well water
Shuang WANG ; Liuchen XU ; Yaowen PEI ; Mei WANG ; Zhenqiang BI ; Huaning ZHANG ; Lu LIU ; Ming FANG ; Zengqiang KOU
Chinese Journal of Epidemiology 2021;42(5):898-902
Objective:To analyze molecular epidemiological characteristics of drug resistance genes and carbapenem resistance of Pseudomonas aeruginosa (PA) in rural well water. Methods:According to Citation of Natural Mineral Water Inspection (GB 8538-2016), a total of 112 well water samples were tested in Juye county of Shandong province, and PFGE and drug susceptibility test were conducted for the identified PA strains. After PCR identification of carbapenem resistance genes, S1-PFGE and Southern blotting were used to determine the location of drug resistance genes, and combined experiments were used to determine gene transferability. Results:The detection rate of PA in rural well water samples in Juye county of Shandong province was 54.46% (61/112). The 61 strains could be divided into 56 PFGE types. There were 2 strains with 100.00% consistent band types, and there was no obvious predominant band type. The results of drug susceptibility experiments showed that 93.44% (57/61) were multi-drug resistant strains, and there were 2 strains carrying blaVIM-2, both of which were located on the plasmid, and both of them were transferred horizontally with the plasmid. Conclusion:PA carrying carbapenem resistance genes was detected in well water of rural communities in Juye country, and there is the possibility of horizontal transmission of such resistance genes.