[Molecular typing of Neisseria meningitidis serogroup C strains with pulsed field gel electrophoresis in China].
OBJECTIVE
To study the characteristics of epidemiology and molecular typing on Neisseria meningitidis serogroup C strains associated with outbreaks of Anhui province and sporadic cases in China, using pulsed field gel electrophoresis (PFGE).


METHODS
212 Neisseria meningitidis serogroup C strains were isolated from invasive meningococcal cases, close contacts and healthy carriers, including 48 strains from Anhui province with 38 strains associated with serogroup C outbreaks. PFGE were performed by genomic DNA digestion with Nhe I restriction enzyme. The results of PFGE were analyzed by BioNumerics software (Version 4.0, Applied Maths BVBA, Belgium).


RESULTS
A total number of 212 Neisseria meningitidis serogroup C isolates were typed by 43 patterns, named AH1 to AH43. In China, AH1 pattern was the major PFGE pattern with 69.3% (n = 147) of all strains, distributed in 11 provinces. Three types of PFGE patterns (AH1 to AH3) were found in 48 strains from Anhui province, in which, 93.8% (n = 45) belonged to AH1. 97.4% (n = 37) of 38 strains associated with serogroup C outbreaks in Anhui province showed AH1 pattern. A total of 53 serogroup C strains were isolated from invasive meningococcal cases with 67.9% (36/53) of AH pattern. 71.9% (87/121) of serogroup C strains isolated from contacts of invasive meningococcal cases was AH1 pattern and 63.2% (24/38) of the strains from healthy carriers showed AH1 pattern.


CONCLUSIONS
By PFGE typing and analysis, AH1 pattern of Neisseria meningitidis serogroup C strains was proved to be the main clone which causing the outbreaks in Anhui province and might be responsible for the sporadic serogroup C meningococcal disease epidemics else where in the country.
Shao
Zhu-Jun
ZJ
National Institute of Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
Ren
Hong-Yu
HY
Xu
Li
L
Diao
Bao-Wei
BW
Li
Wei
W
Li
Ma-Chao
MC
Cui
Zhi-Gang
ZG
Liang
Xiao-Feng
XF
Li
Yi-Xing
YX
Liu
Dan-Qing
DQ
Yang
Meng
M
Zhang
Tie-Gang
TG
Li
Man-Shi
MS
Xu
Jian-Guo
JG
D015373:Bacterial Typing Techniques; D002681:China / Q000453:epidemiology; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D008589:Meningococcal Infections / Q000453:epidemiology*; D038542:Neisseria meningitidis, Serogroup C / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial