Prevalence and characterization of human Shigella infections in Henan Province, China, in 2006.
In 2006, 3,531 fecal samples were collected from patients with diarrhea in Henan Province, China. A total of 467 (13.2%) Shigella strains were isolated and serotyped. Seventy-one Shigella flexneri strains were characterized by MIC determination, pulsed-field gel electrophoresis (PFGE), and detection of genes encoding cephalosporin resistance. Most infections were caused by S. flexneri variant X [IV:(7),8] (27.6%), S. sonnei (24.2%), and S. flexneri 2a (20.8%). However, large regional differences were observed. Significantly higher odds (2.0) of females compared to males were infected with S. flexneri 2a. Untypeable S. flexneri (-:6) isolates were absent among males, as were untypeable S. flexneri [I:(7),8] isolates among females. Patient ages ranged from 2 months to 82 years, with 231 subjects (49.7%) <5 years of age. Most of the patients were male (62.1% [n = 290]). Infections peaked in July; week 27 with 38 cases (8.1%). All of the 71 S. flexneri conferred resistance to nalidixic acid; in addition, 21% (n = 15) and 79% (n = 56) were high- and low-level resistant to ciprofloxacin, respectively. Six S. flexneri isolates {serotype 2b [II:7,(8)] and 2b [II:(3),4;7,(8)]} harbored the bla(CTX-M-14) or bla(CTX-M-15) gene. A total of 52 unique XbaI PFGE patterns were observed among the 71 S. flexneri isolates with 11 distinct PFGE clusters. This study revealed a high prevalence of shigellosis with geographical differences in the distribution of serotypes in the distribution of serotypes and also differences in comparisons by gender. A high frequency of resistance, including 100% resistance to ciprofloxacin and resistance to extended-spectrum cephalosporins, was observed. We detected several isolates exhibiting the same PFGE type and MIC profile, indicating multiple undetected outbreaks.
Branch for Enteric Disease Control and Prevention, Institute for Infectious Disease Control and Prevention, Henan Center for Disease Control and Prevention, Zhengzhou, China.
Shengli
S
Xia
Bianli
B
Xu
Lili
L
Huang
Jia-Yong
JY
Zhao
Lu
L
Ran
Jin
J
Zhang
Haomin
H
Chen
Chaiwat
C
Pulsrikarn
Srirat
S
Pornruangwong
Frank M
FM
Aarestrup
Rene S
RS
Hendriksen
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D024881:Drug Resistance, Bacterial; D004405:Dysentery, Bacillary / Q000453:epidemiology* / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D005243:Feces / Q000382:microbiology; D005260:Female; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058889:Molecular Typing; D015995:Prevalence; D012763:Shigella flexneri / Q000302:isolation & purification*; D012764:Shigella sonnei / Q000302:isolation & purification*; D055815:Young Adult
D000900:Anti-Bacterial Agents