[The etiologic characteristics of Vibrio cholerae in Guangdong province in 2007].
OBJECTIVE
To analyze the etiologic characteristics of Vibrio cholerae in Guangdong province in 2007. Genetic relationship was observed including among predominated biotype isolates from different areas within the province and among same biotypes isolates from cholera cases and regular surveillance.


METHODS
Isolates from cholera cases and through environmental surveillance were typed by sero- and phage- typings. Similarity of molecular fingerprinting was analyzed through comparing the pulsed field gel electrophoresis(PFGE) pattern of predominated biotype isolates, and those of the same biotype isolates from cholera cases a nd environment surveillance, respectively. In addition, genetic relationship was determined by clustering analysis, using bionumerics software.


RESULTS
In total, 31 isolates from cholera cases were collected and subtyped for 3 serogroups. V. cholerae O1 El Tor Inaba phage 1d was the predominant biotype which causing most of the cases in Guangdong province in 2007. Data from cluster analysis showed that the similarity among Inaba phage 1d strains from different areas were from 94.5% to 100%. However, 16 isolates were collected from environment surveillance programs and the predominated biotype could not be found. Additionally, the biotype distribution of cases isolates was not consistent with those isolates through surveillance. High phylogenetic diversity was observed for the same biotypes isolates from cases and surveillance samples.


CONCLUSIONS
Our data showed that V. cholerae O1 El Tor Inaba phage 1d was the predominated biotype with multi-clone coexisting and circulating in Guangdong province in 2007. It also appeared to be the characteristics of cholera in the non-epidemic period, suggesting that it was necessary to enhance the alert surveillance programs for cholera epidemic based on the molecular typing techniques.
Deng
Xiao-ling
XL
Guangdong Province Center for Disease Control and Prevention, Guangzhou 510300, China.
Li
Bo-sheng
BS
Tan
Hai-ling
HL
Sun
Li-mei
LM
Ke
Bi-zia
BZ
Ke
Chang-wen
CW
Wang
Duo-chun
DC
Kan
Biao
B
Zhong
Hao-jie
HJ
D001434:Bacteriophage Typing; D002681:China / Q000453:epidemiology; D002771:Cholera / Q000453:epidemiology / Q000382:microbiology*; D016000:Cluster Analysis; D006801:Humans; D017747:Seafood / Q000382:microbiology; D014734:Vibrio cholerae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D014871:Water Microbiology